Infectious (contagious) diseases occupy a special place among other human diseases. The most important feature of infectious diseases is their contagiousness, i.e. the possibility of transmission from a sick person or animal to a healthy one. Many of these diseases, such as influenza, are capable of mass (epidemic) spread, covering, under appropriate conditions, an entire village, city, region, country, etc. continents.
One of the reasons for the massive spread of infectious diseases is the poor sanitary culture of the population and non-compliance with various sanitary and hygienic rules. In this regard, sanitary squads with appropriate training can play an important role in raising the sanitary culture among the population and instilling hygienic skills in them. Besides, important has a number of anti-epidemic measures, such as sanitary supervision of public catering establishments, the condition of housing and public places. Health workers in this regard can be greatly assisted by sanitary squads. With the massive spread of infectious diseases, especially when the enemy uses bacteriological (biological) weapons, sanitary squads can be involved in many other anti-epidemic measures.
Infectious diseases are caused by microbes (microorganisms) that are very small in size; Study microorganisms using a microscope. Modern electron microscope gives an increase of 200,000 times or more. The sizes of microbes are usually expressed in thousandths of a millimeter - microns. The world of microbes is extremely large and diverse. Microorganisms are found in huge quantities in soil, water, and air. Without the participation of microorganisms, the cycle of substances in nature is impossible. Microorganisms take part in enriching the soil with mineral compounds and nitrogen, decompose corpses and plants (rotting), and participate in many chemical reactions. With the help of certain microbes (yeast), wine, kefir, yogurt and many other products are produced. Numerous types of microbes inhabit the intestines of humans, animals, and live on the skin and in the oral cavity.
Such widely used therapeutic agents as antibiotics (penicillin, streptomycin, chloramphenicol, tetracycline, gramicidin) are products produced by microorganisms.
Along with beneficial microorganisms, there are also harmful microorganisms. Some of them are causative agents of contagious (infectious) diseases of humans, animals and agricultural plants. These microbes are pathogenic.
The following main groups of microorganisms are distinguished.
1. Bacteria are single-celled organisms that reproduce by simple division (Fig. 30).
Some bacteria, such as anthrax and tetanus, under unfavorable conditions form spores with a dense shell, which are very resistant to drying, heat, sunlight, and chemicals.
2. Mushrooms have more complex structure. For the most part, fungi are multicellular organisms, the cells of which have an elongated shape resembling threads.
3. Protozoa are single-celled organisms of animal origin that contain protoplasm and. clearly demarcated core. Some protozoa have vacuoles that perform the functions of digestion, excretion, etc.
Pathogenic microbes produce special substances - toxins that have toxic properties. Toxins released by microbes during their life are called exotoxins. Endotoxins are released only after the death and destruction of the microbial cell and are present in all pathogenic microbes. Exotoxins are produced only by some of them (tetanus bacilli, diphtheria, botulism and a number of other pathogens) and are strong poisons that act primarily on the nervous and cardiovascular systems of the body.
The direct cause of the disease is the introduction of a pathogenic microorganism into the human body or poisoning with a toxin.
Pathogens of infectious diseases are transmitted from sick people to healthy people in various ways. The spread of infectious diseases in the human community is called the epidemic process . This process is a complex phenomenon, which, in addition to the properties of the pathogen and the state of the human body, is greatly influenced by social factors: material condition and population density, the nature of nutrition and water supply, accessibility medical care, degree of sanitary culture, etc.
In the process of spreading infectious diseases, three links are distinguished: 1) the source of the infectious agent; 2) transmission mechanism; 3) receptivity of the population. Without these links, or factors, new infections cannot arise.
Source of infectious agent. In most diseases, the source of the infectious agent is a sick person or a sick animal, from whose body the pathogen is eliminated by sneezing, coughing, urinating, vomiting, and defecation. Sometimes, even after recovery, a person can secrete pathogenic microbes for a long time. Such people are called bacteria carriers (bacteria excretors). In addition, there are so-called healthy bacteria carriers - people who either were not sick themselves or had the mildest form of the disease (and therefore it remained unrecognized), but became bacteria carriers. Sometimes bacteria carriers periodically release pathogens into the external environment for many years. Bacterial carriage is observed in diphtheria, typhoid fever, dysentery and some other diseases.
If the main source of the infectious agent is animals from which humans become infected, such diseases are called zoonoses. A person can become infected from a sick animal not only through direct contact with it (bite by a rabid animal, manual release afterbirth during lambing, carcass processing, etc.), but also when eating meat and milk obtained from sick animals.
The source of the infectious agent can be not only domestic animals, but also rodents. Rats, various types of mice, marmots, gophers, tarbagans, etc. are natural custodians (reservoirs) of pathogens of many human infectious diseases (plague, tularemia, leptospirosis, encephalitis, leishmaniasis, tick-borne relapsing fever etc.).
The mechanism of transmission of the pathogen.After the pathogen is released from the source (infected organism) into the external environment, it may die, but it can persist in it for a long time until it reaches a healthy person. The survival time of the pathogen depends both on environmental conditions and on the properties of the pathogen itself. In food products, such as meat, milk, and various creams, the causative agents of many infectious diseases can live for a long time and even multiply.
The transmission of pathogens involves water, air, food products, soil, etc.
Foodtransmission route of infectious agentssicker is one of the most common. The causative agents of typhoid fever, cholera, dysentery, brucellosis, Botkin's disease, polio, etc. are transmitted in this way. In this case, the causative agents of these diseases can get on food products in various ways. This can happen both from a sick person or bacteria carrier, and from people around him who do not follow the rules of personal hygiene. If their hands are contaminated with feces of a sick person or a bacteria carrier containing pathogens, they can transfer them to the processed food products. Therefore, intestinal infectious diseases are sometimes called “dirty hands disease.”
Flies play a certain role in the spread of pathogens of intestinal infectious diseases. Sitting on dirty bedpans, feces, and various sewage, flies contaminate their paws and absorb pathogenic bacteria into their intestinal tube, and then transfer them to food products and dishes.
The causative agents of cholera, typhoid and paratyphoid fever, dysentery, tularemia, brucellosis, leptospirosis, etc. can be transmitted through water contaminated with feces. Transmission of pathogens occurs both when drinking contaminated water, and when washing food with it, as well as when swimming in it. The pathogen is transmitted through the air by talking, exhaling, kissing, but more often by coughing and sneezing with droplets of mucus (“droplet transmission of the pathogen”). Some germs can also be transmitted via dust particles (dust pathway).
Many pathogens of infectious diseases are transmitted by blood-sucking arthropod vectors. Having sucked on the blood of a sick person or animal containing pathogens, the carrier becomes infectious. Then attacking a healthy person, the carrier infects him. In this way, fleas transmit the causative agent of plague, lice - typhus and relapsing fever, mosquitoes - malaria, ticks - encephalitis, etc.
In cases where pathogens are transmitted through contact of a patient or his secretions with a healthy person, they speak of a contact-household route of transmission.
Population sensitivity. Everyone knows that people’s susceptibility to various pathogens of infectious diseases varies. There are pathogens to which all people are susceptible (smallpox, measles, influenza, etc.). On the contrary, susceptibility to other pathogens is very low. The susceptibility of the population can be significantly reduced by carrying out preventive vaccinations aimed at increasing specific immunity (immunity).
Immunity is a property of the body that ensures its immunity to infectious diseases or poisons.
The human body has a number of protective devices that prevent the penetration of pathogenic microbes or due to which they die in the body. First of all, it is necessary to note the great protective role of the skin and mucous membranes. Saliva, tears, gastric and intestinal juices have antimicrobial properties. Further spread of germs is prevented lymph nodes, in which microbes linger and then die.
The founder of the doctrine of immunity, the great Russian scientist I. I. Mechnikov (1845-1916), established that white blood cells - leukocytes are capable of capturing living pathogenic microbes and destroying them. This phenomenon was called phagocytosis by I.I. Mechnikov. Along with phagocytes, special substances are important for the state of immunity of the body - antibodies, which are found mainly in the blood, lymph and many tissues.
A lot of antibodies accumulate in the blood of animals (for example, horses) if they are repeatedly injected subcutaneously with killed microbes or neutralized toxins. Specific therapeutic serums are prepared from the blood of such horses.
Immunity to infectious diseases comes in several forms.
Natural immunity occurs naturally, without conscious human intervention, for example as a result of an infectious disease. After some infectious diseases (smallpox, measles, typhoid fever, etc.), immunity lasts for a long time, sometimes for life, after others (influenza) - for a short time. Natural immunity to certain diseases (measles, scarlet fever, diphtheria) is also observed in children in the first months of life, which is associated with the preservation of the protective bodies they received from mothers who had suffered from these diseases in the past.
Artificial immunity is created by administering vaccines or serums to prevent a particular disease. Drugs that can be used to artificially create immunity in the body, i.e. immunity, are called vaccines and toxoids. Currently, a variety of vaccines are produced: 1) from live attenuated pathogens; 2) from killed microbes; 3) chemical vaccines prepared from products of chemical breakdown of microbial cells; 4) toxoids, which are neutralized toxins.
Immunity after the introduction of killed vaccines is shorter (up to 1 year) than after the introduction of live ones, in which immunity sometimes lasts for 3-5 years. After the specified period, revaccination (re-vaccination) is carried out.
In the USSR, vaccinations against smallpox, diphtheria, tuberculosis, polio and some other diseases are mandatory and are given to all children, and smallpox vaccinations are also given to adults. In addition, there are combination vaccines; After vaccination with such a vaccine, immunity against several diseases occurs.
Widespread preventive vaccinations have proven to be a highly effective method of combating infectious diseases. Suffice it to recall that the implementation of compulsory smallpox vaccination, established in our country back in 1919 by decree of the Council People's Commissars signed by V. I. Lenin, ensured success in the fight against smallpox, this serious disease completely eradicated on the territory of the Soviet Union.
It should be emphasized that the basis for the prevention of infectious diseases is the implementation of broad sanitary and hygienic and general anti-epidemic measures, and the use of preventive vaccinations is of auxiliary importance. First of all, success is ensured by general sanitary measures, which are carried out regardless of the presence of diseases. This includes sanitary control over water supply and food enterprises, cleaning populated areas from sewage, combating the breeding of flies, draining swamps, introducing water supply and sewerage systems, etc. General sanitary measures play a role decisive role, especially in the prevention of intestinal infectious diseases. Early detection and isolation of infectious patients are of great importance in stopping further transmission of the infectious agent. In most cases, they are hospitalized in specialized infectious diseases departments or hospitals, and only for some infectious diseases (scarlet fever, measles, influenza, in some cases dysentery) isolation at home is allowed. In these cases, all possible measures to isolate the patient from others are taken under the given conditions: he is placed in a separate room or, in extreme cases, behind a screen, the patient’s secretions are neutralized, etc. Infectious patients are strictly prohibited from visiting public places, including an outpatient clinic and a clinic.
Infectious patients are transported by special transport. After each patient, the car is subjected to treatment (disinfection, disinfestation).
A significant place in the comprehensive prevention of infectious diseases belongs to the promotion of hygienic and cultural skills among the population. The sanitary guard must be an active assistant to the doctor and nurse in carrying out sanitary educational work and set an example in observing hygienic and cultural skills. In a conversation, she can talk about the source of a particular infection, the ways of its spread, teach others the simplest preventive measures: isolating the patient, ventilating the room, neutralizing dishes and household items by boiling, etc.
If necessary, sanitary guards can be involved in conducting door-to-door visits, the purpose of which is to identify all febrile patients during an epidemic outbreak of certain diseases for subsequent hospitalization.
Disinfection, disinfestation and deratization play a huge role in suppressing further transmission of the infectious agent;
Disinfection - disinfection. In the practice of disinfection, there are two types: focal and preventive.
Preventive disinfection is carried out with the aim of improving the health of populated areas and preventing the occurrence of diseases, regardless of their presence. This includes ventilation of rooms, wet cleaning of rooms, washing hands before eating, cleaning and chlorination of tap water at a water pumping station, pasteurization and boiling of milk, canning food, etc.
Focal disinfection is carried out in cases where it becomes known about the appearance of a disease in a family, hostel, or child care facility, i.e., in an epidemic focus. Depending on the stage at which disinfection is carried out, a distinction is made between current and final disinfection.
Current disinfection is carried out at the source of infection in order to destroy pathogens immediately after their release from the patient’s body. For this purpose, every portion of feces and urine is neutralized if we are talking about intestinal infections, sputum of patients with tuberculosis, etc.
Objects used by the patient and his underwear are also disinfected, as they may be contaminated with feces containing pathogens. Walls, floors, beds, bedside tables are systematically washed with disinfectant solutions, washed with soap, and boiled toys, linen, and dishes.
One of the most important aspects of ongoing disinfection is strict adherence to personal hygiene rules and the development of appropriate skills by all caregivers.
Final disinfection is carried out by specially trained disinfectors after the patient’s hospitalization, recovery, transfer to another room, or death.
Disinfection is carried out using physical and chemicals. One of the ways to physically purify tap water is filtration. Direct sunlight also has a detrimental effect on many pathogenic microbes.
They are highly bactericidal ultraviolet rays. To obtain them, mercury-quartz and uviol lamps are used, which are used to disinfect the air and surfaces of various indoor objects.
Dishes, bedpans, spittoons, surgical instruments, syringes, needles, brushes, etc. are disinfected in boiling water for at least 45 minutes. Linen is also often disinfected by boiling.
Chemical methods of disinfection are the most common. Various chemicals are used for disinfection: phenol, cresols, Lysol, alcohols, various alkalis and acids, bleach, etc. Disinfection is carried out according to special instructions approved by the USSR Ministry of Health.
The most commonly used is bleach, from which, when decomposed, free oxygen and free chlorine are released, which have a detrimental effect on the life of the microbial cell. Chloride of lime is used to disinfect secretions from intestinal infections (typhoid fever, paratyphoid fever, dysentery, cholera, etc.), respiratory diseases (diphtheria, tuberculosis), plague, anthrax, etc., as well as disinfection of linen and dishes.
Formaldehyde, a 40% aqueous solution of formaldehyde, is widely used to disinfect outer clothing, bedding, books and other items. Disinfection is carried out in special disinfection chambers.
Along with stationary cameras, there are also mobile installations on the car. Thus, the mobile steam-formalin chamber APKD (Fig. 31) has two chambers and a device that allows people to be washed in the shower at the same time as disinfecting things. Movable chambers allow disinfection in field conditions and small settlements.
Disinfection of room surfaces (floor, walls) and objects in them that cannot be sent to a disinfection chamber is carried out by spraying solutions
disinfectants under high blood pressure from special pumps and hydraulic controls (Fig. 32).
Disinsection - getting rid of insects and other arthropods - is a subtype of disinfection. Just like disinfection, disinsection is carried out using physical, chemical and biological means.
Physical methods of disinsection are basically the same as disinfection. This is mechanical cleaning of things with brushes, beating, suction with a vacuum cleaner, burning of low-value items. Sticky masses and various traps are widely used to kill insects. Lice and nits on linen can be destroyed by carefully ironing with a hot iron. Wearable items and soft equipment (mattresses, blankets, etc.) are disinfested in hot-air chambers. The design of such cameras is very simple. In the absence of a special chamber, a Russian oven can be used.
Chemical methods of disinfestation are based on the ability of certain chemicals to provide toxic effect on arthropods. The most commonly used are Paris greens, DDT (dichlorodiphenyltrichloroethane), hexachlorocyclohexane (HCH, hexachlorane), chlorophos, etc. It must be remembered that almost all of these drugs are toxic to humans. Therefore, it is imperative to work with powders or aerosols (tiny particles of a substance suspended in the air) in a respirator mask, with solutions and emulsions - in rubber gloves and clothes that protect the skin, and take measures to protect food and water from contact with insecticides ( This is the name given to chemicals that have a detrimental effect on arthropods). As a means of personal protection against attacks by blood-sucking insects, repellents are used - substances that repel arthropods: dimethyl phthalate, diethyltoluamide (DET), kyuzol, etc. Insect repellents are included in ointments, creams, lotions recommended for individual protection against insect attacks in the taiga and tundra. .
Deratization - freeing from rodents - is aimed at eliminating the source of the infectious agent; in many diseases it is rodents. Extermination measures are carried out using biological, chemical and mechanical methods.
Chemical methods of deratization involve the use of various poisons, usually mixed with bait (bread, cereals, vegetables, etc.). For different types rodents use various poisons and baits: ratsid, zinc phosphide, zoocoumarin, etc.
Biological methods of exterminating rodents come down to the use of cats, rat-catching dogs, etc., mechanical methods - to the use of traps and snares.
Source---
Tutorial for sanitary squads. M.: Medicine, 1972.- 192 p.
14.10.2013 30120 0Lesson objectives. To familiarize students with the signs of infectious diseases, conditions and mechanisms of transmission. Introduce students to the most common infections and their mechanisms of transmission. Explain the mandatory rules of personal hygiene to prevent infectious diseases.
Checking homework.
1. Answer the questions.
Formulate your definition of health. What is the definition of health according to the WHO charter?
What components does the concept of “health” include?
List the main functions of health.
What is individual health and what does it depend on?
-What's happened public health and what factors influence it?
Name the main types of environmental pollution.
Give examples of chemical pollution.
Briefly describe physical pollution
Briefly describe biological contamination.
What is immunity?
What types of “social pollution” of society do you know? Briefly describe them.
Learning new material. Introductory word from the teacher.
In the last lesson we talked about biological pollution of the environment, biological pollutants. Human infectious diseases are one of the manifestations of such pollution.
Questions to activate knowledge.
What is an infection?
What is an infectious disease?
What are the characteristic signs of infectious diseases?
How are infectious diseases transmitted?
What is an epidemic?
What is hygiene?
How does compliance with hygiene rules affect a person’s likelihood of contracting an infectious disease?
You can start studying new material by defining the term - infection.
Infection(from the medieval Latin word infectio - infection), the introduction and reproduction of pathogenic microorganisms in the human or animal body, accompanied by a complex of reactive processes; ends with an infectious disease, bacterial carriage or death of microbes. The source of the infectious agent infects healthy people through contact, through the mouth (with water and food), air (with droplets of saliva and mucus), and arthropod carriers.
Infection, or more precisely, the process denoted by this term, underlies the existence of a special kind of disease - infectious.
Infectious diseases - diseases caused by pathogensmicroorganisms that are transmitted from an infected person to health rov. Each infectious disease is caused by a specific pathogen.
The causative agents of infectious diseases have a number of characteristics:
1. The ability to be transmitted from sick to healthy and thus spread among people, causing epidemics.
2. The presence of an incubation period for reproduction in the body.
3. Difficulty of detection in the external environment.
4. The ability of some pathogens to persist for a long time outside the human or animal body.
Epidemic (Greek epidemia) - a massive spread of a human infectious disease in any area or country, significantly exceeding the normal incidence rate.
Conditions for transmission of infection, as mentioned above, many.
Scientists highlight three main groups conditions:
Natural - climate, landscape, flora and fauna, the presence of natural (endemic for a given area) foci of infectious diseases, hydrography, wind rose, the presence of natural disasters.
Social- population density, housing conditions, sanitary and communal structure of settlements, material well-being, the state of the health care system, migration processes, the state of the transport system, the general development of the sanitary culture of the population, working conditions, nutritional structure and others.|
Personal- the body’s ability to respond to the introduction, reproduction and vital activity of pathogenic microorganisms, to the development of the infectious process with a complex of protective and adaptive reactions. Personal transmission conditions are usually referred to as susceptibility.
The causative agents of infectious diseases have different resistance in the environment: some are able to live outside the human body for only a few hours, others can live in the environment from several days to several years. For others, the environment is their natural habitat. For others, other organisms, such as wild animals, provide a place for conservation and reproduction.
These features depend mechanisms of transmission of infectious diseases diseases.
Under transmission mechanism pathogenic microbes understand the set of evolutionarily established ways of moving pathogens from an infected organism to a healthy one. It includes: removing the pathogen from the infected body; his presence in the external environment; introduction of a pathogen into a healthy body. There are several approaches to classifying the mechanisms of transmission of infectious diseases. They differ only in details. At home you will become familiar with the classification given in the textbook (see pp. 132-133). The teacher asks you to write it down in your notebook. one of the classifications of methods of transmission of infection.
Fecal-oral (for intestinal infections).
Airborne (for respiratory tract infections).
Liquid (for blood infections).
Contact (for infections of the external integument).
Zoonotic (vector - animals).
Thus, infectious diseases arise under unfavorable conditions for humans and society. Typically, infectious diseases spread from their natural habitat through transport routes and mass migrations of disease-carrying animals. When the percentage of cases is much higher than usual, they speak of an epidemic. Their scale depends on natural and social conditions. The disease of a particular person depends on his susceptibility, i.e. the body's ability to resist infection. There are various mechanisms of transmission of infection, on the basis of which infectious diseases are classified.
Infectious diseases pose a great danger to humanity. In the Middle Ages, epidemics carried away the population of entire states, leaving behind deserted cities and throwing back entire civilizations. This cannot be allowed to happen. Epidemics arise and spread in different ways, the diseases that give rise to them have different transmission mechanisms. It is necessary to know this mechanism, because the rules for the safe behavior of each person in an epidemic are determined precisely by the mechanism of infection transmission.
Currently, infectious diseases of “dirty hands” are quite widespread throughout the world, including our country. The mechanism of their transmission is fecal-oral. They usually occur in the summer, spread very quickly and sometimes lead to epidemics. Such diseases include:
Cholera (Greek cholera, from chole bile + rheo to flow, bleed) - an acute infectious disease, characterized by damage to the gastrointestinal tract, a violation water-salt metabolism and dehydration of the body; refers to quarantine infections. In the history of mankind, cholera periodically spread to many countries of the world and entire continents, killing millions. human lives. The last, seventh, pandemic of the disease began in 1961. The epidemic situation of cholera in the world remains tense, with several thousand people falling ill every year. In the countries of South and Southeast Asia and in a number of African countries (more than half of the disease cases are recorded on the African continent), there are endemic foci of cholera and epidemics periodically occur.
The causative agent is Vibrio cholerae Vibriocholerae- similar to a comma, very mobile, grows well on nutrient media with an alkaline reaction. Vibrios cholerae tolerate low temperatures, can overwinter in frozen bodies of water, and survive for a long time in coastal waters of the seas. Boiling kills vibrios instantly. They are sensitive to drying, sunlight, and disinfectants. In the water of surface reservoirs in the warm season, it is even possible for Vibrio cholera to multiply, which is facilitated by water pollution with waste with an alkaline reaction, especially bath and laundry waste.
The source of the infectious agent is only a person - a patient or a carrier of vibrio cholerae. Cholera is transmitted only by the fecal-oral mechanism. The main route of transmission is water - through the use of contaminated water for drinking, washing dishes, vegetables, fruits, while bathing, etc., as well as through contaminated food and household contacts. Human susceptibility to the disease is high.
When a cholera outbreak occurs, sanitary control points are created on railway, water and air transport, and on highways to identify and hospitalize patients with gastrointestinal disorders in order to prevent the importation of cholera. The fireplace is subject to repeated disinfection. In some cases, for epidemic reasons, emergency prophylaxis of the entire population with antibiotics is carried out in the outbreak. During the year after the elimination of a cholera outbreak, constant monitoring of compliance with sanitary and preventive measures in the given territory is carried out. Conducted at least once every 10 days bacteriological examination water from drinking water supply sources, open reservoirs and domestic waste water for the presence of cholera vibrios.
Dysentery. The causative agent is a dysentery bacillus. Retains its properties: in feces, in linen, in damp soil, in milk, on the surface of fruits, berries, vegetables, paper and metal money. Dies in the spring environment under the influence of high and low temperatures, sun rays, disinfectants. A temperature of 60 °C and a 1% solution of carbolic acid kills it in 30 minutes. Sources: sick or recovering people. Infection occurs through dirty hands, contaminated objects and food. The carriers are flies. The disease is recorded throughout the year, with its peak occurring in July-August.
Prevention of dysentery is strict adherence Lich rules hygiene, food hygiene andtimely detection of bacilli carriers
Infectious (epidemic) hepatitis- Botkin's disease. The causative agent is a special type of filterable virus (a virus passing through a bacterial filter). It primarily affects the liver and is found in the blood, bile and feces of a sick person. It is stable in the external environment and therefore very dangerous.
Infection of a healthy person can occur in two ways: through the gastrointestinal tract (with water and food), and also through blood (using a poorly sterilized syringe, transfusion of uncontrolled blood, during surgery, through a drug addict’s needle). The incubation period is up to 50 days, and when infected through blood - up to 200 days. A healthy person who has had Botkin's disease poses a danger because... The virus remains in his blood even after recovery. The main means of prevention is mandatory compliance with the requirements of personal hygiene and food hygiene.
Diphtheria . The causative agent is a bacillus that is highly resistant in the external environment and releases a very strong toxic substance. Sources - a sick or recovering person. Infection most often occurs by airborne droplets when sneezing and talking, but infection through books, toys, and food is also possible. The entry gate of the pathogen is the mucous membrane of the nose, pharynx, eyes, damaged skin. The incubation period lasts from 2 to 7 days. Depending on the location, diphtheria is distinguished in the pharynx, throat, nose, eye, ear, skin and even the external genitalia. If wounded, diphtheria of wounds is possible. The disease begins acutely. The temperature can rise to 38-39 °C, which is accompanied by headache and weakness.
Prevention of diphtheria consists, first of all, in immunization of children, revaccination of adults and identification of bacilli carriers. In case of an outbreak of diphtheria, quarantine is organized for 7 days from the moment of the last illness. During these days, the body temperature of those in contact with the patient is monitored and their condition is carefully monitored. The premises are disinfected, dishes and children's toys are treated with a disinfectant solution and boiling water.
Sexually transmitted infections. Sexually transmitted diseases are infectious diseases whose pathogens are transmitted from a sick person or carrier to a healthy one. They can be transmitted not only sexually, but also through close household contact (through shared utensils, etc.), in utero. Diseases transmitted not only through sexual contact include: ureaplasmosis, trichomoniasis, genital herpes. This group also includes HIV infection.
HIV infection. AIDS, acquired immunodeficiency syndrome. This is a disease immune system the human body, leading to its destruction.
Symptoms of this disease were first reported in 1978 in several patients in the United States and Sweden (in homosexual men), as well as in Tanzania and Haiti (in heterosexuals of both sexes). And in 1983, Luc Montagnier from the Pasteur Institute (France) discovered the human immunodeficiency virus (HIV), which is the cause of AIDS. It is now known that this virus comes from West Africa, its nature and structure have been determined, the transmission routes and viability of the virus have been studied, but so far all this has not led scientists to create a medicine to treat HIV. The statistics on the spread of HIV infection are terrifying: at the moment 40 million people in the world are already infected with HIV or have AIDS.
There are several ways of contracting HIV infection:
1. Unprotected (without a condom) sexual intercourse (70-80%);
2. Sharing of syringes, needles and other injection equipment (5-10%);
3.Use of non-sterile instruments for tattoos and piercings;
4.Use of other people's shaving equipment, toothbrushes with visible blood residues;
5.Transfusion of infected blood (5-10%);
6. Transmission of the virus from an HIV-positive mother to a child - during pregnancy, childbirth and breastfeeding (5-10%).
A person living with HIV may look and feel fine for many years and not even know that they are infected. However, over time, the virus continues to destroy cells of the immune system, and when the number of cells drops below critical levels, a person becomes vulnerable to diseases, many of which are usually avoidable. The diagnosis of AIDS (acquired immunodeficiency syndrome) is usually made several years after HIV infection, when a person develops one or more serious illnesses. For example, early signs of progression of HIV infection include oral thrush, unexplained fever, night sweats, diarrhea, weight loss, frequent acute respiratory infections, herpes zoster, etc.
A blood test for HIV can be done in any hospital, including anonymously. Regarding HIV infection and test results, you can consult with an immunologist or venereologist, who, if necessary, will prescribe treatment. To avoid the risk of contracting HIV, it is necessary to follow some rules of personal safety, especially in the intimate area.
Of the diseases transmitted through zoonotic transmission mechanism, the greatest danger in our country is malaria, encephalitis and rabies.
Malaria, also known as swamp fever, intermittent fever, paroxysmal malaria, an acute infectious disease caused by several species of protozoa Plasmodium and transmitted by the bite of a mosquito of the genus Anopheles.
Malaria is characterized by repeated attacks of severe chills, high fever and profuse sweating. It is widespread in warm and humid regions with an average annual temperature of 16 ° C and above, it is also found in zones of more temperate climates and is completely absent in the polar regions. The disease causes serious economic damage to countries with tropical and subtropical climates, leading among all diseases as the main cause of disability and mortality.
Malaria remains a fairly common disease in many other regions. It is found in the West Indies, Mexico, Central America, and in the northern regions of South America, especially in the Amazon Valley. Malaria is a constant threat to many parts of Africa. It is also common on the coast of the Red and Mediterranean Seas, in the Balkans and Ukraine. Numerous cases of malaria are reported each year in Southeast Asia, India and northern Australia. In the United States, the highest incidence of malaria was in the South, especially Florida.
Only female mosquitoes carry the pathogen, because in males, the piercing and sucking parts of the oral apparatus are reduced. Mosquitoes are the primary host of Plasmodium falciparum, and humans are the intermediate host.
Measures to limit the number of mosquito vectors are aimed at destroying their larvae, which live in the subsurface layer of quiet water bodies. For this purpose, wetlands are drained, an oil film is applied to the surface of reservoirs, insecticides are sprayed, and small fish that feed on mosquito larvae are bred.
In places where such activities are not carried out, insect repellents should be used. However, repellents provide incomplete and short-lived protection.
Tick-borne encephalitis (spring-summer, taiga, Far Eastern, Russian encephalitis). In 1935, a filterable virus, the causative agent of encephalitis, was isolated and the route of transmission was shown: from rodents, through ixodid ticks, the main carriers of spring-summer encephalitis. In addition to a tick bite, infection is also possible by consuming the milk of infected animals. In addition to rodents, birds, wild and domestic animals, as well as ticks themselves can be reservoirs of the virus.
The incubation period lasts from 1 to 30 days. The disease begins suddenly with chills, a rapid increase in body temperature to 38-39 ° C, severe headache, pain throughout the body, weakness, weakness, sleep disturbances, nausea, and sometimes vomiting. From the 3-5th day of illness, damage to the nervous system begins.
Tick-borne encephalitis mainly affects people living or working in wooded and taiga areas (loggers, hunters, geologists, oil workers, etc.), and visitors get sick more often than indigenous residents.
When a tick bites, the virus enters directly into the patient’s blood and then spreads through the bloodstream, reaching its maximum concentration in the brain 3-4 days after the bite. The severity of tick-borne encephalitis depends to a certain extent on the number of bites and the number of viruses that enter the body during each bite.
After an illness, a strong immunity appears, in the blood of those who have been ill during those Over a long period of time, specific antibodies are detected.
Rabies - a viral disease that occurs with severe damage nervous system and usually ending in death.
The disease has been known to mankind for several millennia. First described by C. Celsus in the 1st century. n. e. In 1885, L. Pasteur received and used the vaccine to save people bitten by rabid animals. The viral nature of the disease was proven in 1903 by P. Remlenger.
The virus is resistant to phenol, freezing, and antibiotics. Destroyed by acids, alkalis, and heat.
The virus is dangerous for most warm-blooded animals (mammals and birds).
The source of infection is infected animals: foxes, wolves, dogs, cats, bats, rodents, horses, small and cattle. Human infection occurs when an animal bites or salivates on damaged skin or mucous membranes. The virus is released into the external environment with the saliva of an infected animal or person. Cases of human illness as a result of bites from apparently healthy animals have been described. Transmission of the virus from person to person cannot be ruled out.
Rules of personal and public hygiene.
When talking about infectious diseases, we often mentioned the word “immunity”. Immunity – the ability of the human and animal body to specifically respond to the presence of a foreign substance in it. This reaction of the body provides its resistance and is therefore important for its survival. The reaction is based on the synthesis of special proteins, the so-called. antibodies that can combine with foreign substances - antigens. The science that studies the mechanisms of immunity is called immunology.
Thus, immunity determines the ability of a living organism, including humans, to resist all harmful external influences, such as pathogens. But we often come across the fact that one person practically does not get sick, while the other becomes a victim of any infection. This happens because people have different levels of immunity. Many factors influence the level of immunity.
Vaccination. We also talked about it when we studied infectious diseases. However, this concept also needs to be given a scientific basis. Currently, the concept of vaccination has been revised and the term is used "vaccination And immunization".
Artificial active immunization- stimulation of the immune system by administering a vaccine or toxoid (neutralized bacterial toxin that retains its antigenic properties); With artificial passive immunization, ready-made antibodies - immunoglobulins - are introduced into the body. Natural active immunization of the body occurs as a result of its infection, and natural passive immunization - when maternal antibodies are transferred to the fetus through the placenta or into the newborn’s body with colostrum.
As a result of artificial immunization, highly specific immunity is developed, i.e. a vaccine, toxoid or ready-made antibodies give the body partial or complete resistance to a given disease. Vaccines and toxoids protect the body for a long time, sometimes until the end of life. Ready-made antibodies provide only temporary protection; in case re-infection they need to be entered again. There are two possible ways of artificial active immunization: 1) the introduction of living but weakened microorganisms and 2) the introduction of killed microorganisms, their toxins or antigens. In both cases, a person is given a vaccine or toxin that does not itself cause disease, but stimulates the immune system, making it able to recognize and neutralize a specific microorganism.
Currently, vaccinations are given against many childhood diseases - whooping cough, polio, measles, mumps, rubella and influenza B ( main reason meningitis in childhood). Immunoglobulins have been obtained that can quickly protect the body from snake bites, tetanus, botulism and diphtheria.
Sanitary and hygienic measures - a set of organizational, technical, economic, medical and other measures aimed at preserving the health of the population. The methods of carrying out these activities take into account the nature and working and living conditions of people, their physical development, degree of exposure to occupational and infectious diseases.
The basis of sanitary and hygienic measures is the implementation of preventive and ongoing state sanitary supervision: control over the implementation of national measures aimed at eliminating and preventing environmental pollution, improving the working and living conditions of the population, as well as the implementation by departments, enterprises, organizations and individual citizens of sanitary -hygienic and sanitary and anti-epidemic rules.
Preventive sanitary supervision implies preliminary hygienic assessment new industrial enterprises, new consumer goods, new building materials, etc.
Current sanitary supervision provides for regular planned monitoring of compliance with the established sanitary and epidemiological regime for the operation of enterprises, institutions and structures, the sanitary condition of populated areas, working conditions, etc.
A special place among sanitary and hygienic measures is occupied by prevention infectious diseases - a set of measures aimed at preventing diseases.
It is carried out mainly by the sanitary and epidemiological service and includes the following main activities: disinfestation, disinfection, deratization, quarantine, observation.
Summing up the lesson.
Questions to consolidate knowledge.
What is an infection?
Define an infectious disease.
What are the characteristics of pathogens of infectious diseases?
Define an epidemic and give examples from the history of our country and world history.
Name the conditions for the occurrence of epidemics.
What is receptivity?
Name and briefly describe the mechanisms of infection transmission.
Name the most dangerous diseases transmitted by the fecal-oral route.
What preventive measures are used to prevent these infections?
What are the signs of dysentery in a person? Viral hepatitis? Cholera?
What are the characteristics of botulism infection?
Name the most dangerous diseases transmitted airborne droplet way.
Name preventive measures in the event of a threat of influenza epidemic.
––What is a zoonotic mode of transmission?
How does a person become infected with encephalitis?
What measures are usually taken to control the spread of malaria?
Summing up the lesson.
Homework.
Determine the mechanism of transmission of the most widely known infectious diseases:
Flu is airborne.
Dysentery - fecal-oral.
Viral hepatitis (Botkin's disease) - fecal-oral.
Human immunodeficiency virus (HIV) is a liquid virus.
Leprosy (leprosy) - contact.
Malaria is zoonotic.
Typhoid fever - fecal-oral.
Relapsing fever is zoonotic.
Subject: « Infectious diseases and their prevention."
Prepared by: Rashidova H.A.
Objectives:
Familiarize yourself with the main types of infectious diseases.
Tasks:
1 . Identify mechanisms of transmission of infectious diseases.
2.Study measures to prevent common infectious diseases.
I .Introduction. Relevance of the problem.
Even in ancient times, various infections terrified humanity; epidemics of various diseases devastated cities and countries, killing millions of people. Entire nations were on the verge of extinction; the so-called “pestilence” was considered one of the worst punishments in the whole world, and measures to combat it were sometimes decisive and merciless. Sometimes huge territories with all people and property were burned out in order to prevent the spread of the deadly disease further. In the modern world, medicine has learned to fight and prevent many of those terrible infections that in the Middle Ages became the scourge of society, which became the reason for some of the euphoria that gripped humanity in the mid-twentieth century. But the joy of success in the fight against previous diseases was somewhat premature, since they were replaced and continue to be replaced by new infectious diseases that could potentially destroy a significant number of people.
Throughout recorded history, the greatest scourge for humanity has been plague, smallpox, cholera and yellow fever, which have claimed the lives of large numbers of people.
However, the battle against infectious agents is still ongoing and the only infectious disease successfully eradicated in the world is smallpox.
Elimination of other diseases, such as tetanus, measles, whooping cough, diphtheria and polio, for which effective immunization is quite feasible on a global scale, has now been achieved by more than 90%.
High immigration of people from “third world” countries has led to sharp increase number of people suffering from infectious diseases.
While humanity has managed to learn to control old epidemics, new ones have emerged. It should be noted that there is an ongoing epidemic of human immunodeficiency virus (HIV) infection, which is accompanied by devastating consequences not only in Africa and Asia, but also in Europe and North America.
Despite the improvement in living conditions economically developed countries, the widespread practice of vaccinations and the availability of effective antibiotics, infectious diseases still occupy a significant place in the structure of human morbidity and mortality and are second only to diseases cardiovascular system and malignant oncological diseases. Most deaths among children are infectious diseases of the respiratory system and intestines caused by viruses and bacteria.
Hepatitis A is a widespread infectious disease caused by the hepatitis A virus. Periodic increases in incidence are characteristic, especially in the summer and autumn months.Infectious diseases, as in previous years, continue to occupy one of the leading places among human diseases. Remain current problems viral hepatitis, acute intestinal infections. Long-forgotten diphtheria has returned from past years, tuberculosis has become widespread, new infections caused by herpes viruses, Borrelia, chlamydia, etc., AIDS poses a threat to humanity. In the context of socio-economic changes that led to the stratification of society and the emergence of a large number of socially unprotected people, many infectious diseases acquired severe course, often with fatal consequences. Influenza and ARVI remain one of the most pressing medical and social issues. economic problems and an example of this is the epidemiological situation in our city and in the Saratov region in January - March of this year. I went to clinic No. 3 and took data on ARVI and influenza for the period from February 4th to 18th and found out that the number of people sick during this period was 6884 people, 3749 of them were children. I chose the topic “Infectious diseases” because I think this problem is very important and difficult to solve. After looking through and reading a large amount of literature about infectious diseases, I decided to tell you about them, as well as their prevention.
II . Main part.
2.1What are infectious diseases?
Infectious diseases - this is a group of diseases caused by the penetration of pathogenic (disease-causing) microorganisms into the body. In order for the pathogenic microbe to causeinfectious disease , he must havevirulence , that is, the ability to overcome the body’s resistance and exhibit toxic effects. Some pathogenic agents cause poisoning of the body with exotoxins released by them in the process of life (tetanus, diphtheria), others release toxins (endotoxins) during the destruction of their bodies (cholera, typhoid fever).
At the endXVIIIcentury, the French scientist Louis Pasteur refuted the theory of spontaneous generation of microorganisms. He isolated the causative agents of anthrax, rubella, and rabies, and proposed a method for disinfecting food products (pasteurization). L. Pasteur is rightfully considered the founder of modern microbiology and immunology.
Hippocrates also drew attention to the fact that diseases are preceded by certain environmental conditions and the state of people’s health. Infectious diseases can occur when there is three components when exists:
source of infectious agents (infected person or animal);
a factor that ensures the transmission of pathogens from an infected organism to a healthy one;
people susceptible to infection.
The ability to cause disease varies among different microorganisms. It determines the ability of pathogens to penetrate certain organs and tissues, multiply in them and release toxic substances.
2.2Sanitary and epidemiological situation in the Russian Federation and in the city of Balakovo.
The 20th century gave rise to unjustified optimism that infectious diseases would soon be eliminated. However, the events of recent decades have shown that infections such as tuberculosis and malaria, which are becoming the main cause of mortality, have sharply intensified in the world; both in Russia and in other countries, diphtheria is re-emerging. The epidemiological situation in recent years, remains tense. Every year from 33 to 44 million cases of infectious diseases are registered in the Russian Federation. Influenza and ARVI remain one of the most pressing medical and socio-economic problems. In the period from January to March 2013, in the Saratov region and on the territory of the BIS, an excess of the long-term average incidence of ARVI and influenza was observed by 35%.
Serious problem Viral hepatitis continues to be a major problem in public health, causing damage to both the health of the population and the country's economy.On the territory of the Balakovo municipal district since August 2012. there is a deterioration in the epidemiological situation regarding the incidence of acute viral hepatitis A
Hepatitis A is a widespread infectious disease caused by the hepatitis A virus. Periodic increases in incidence are characteristic, especially in the summer and autumn months. In the territory of the BIS for 8 months of 2012, 46 cases of hepatitis A were registered, which is 4.3 higher than the incidence rate of hepatitis A for the same period last year. According to operational data, the situation regarding the incidence of this infection has become more complicated. As of October 18, 2012, another 22 cases were identified. Every day 2-3 new cases of this disease are registered.
The situation is especially difficult with regard to socially determined diseases. Since 1992, the incidence of tuberculosis began to increase in the country with an annual increase of 10-15%.
Based on the coverage of the population with preventive examinations for tuberculosis at the end of 2012. the figure was 75.5%. To combat this terrible disease, federal and regional programs were adopted, which made it possible to significantly reduce the prevalence of this disease.
The incidence of tuberculosis (in the Saratov region - 61.5 cases per 100 thousand population, in Balakovo and Balakovo region 55.9. Compared to 2011, we have seen an increase in incidence.
The rapid growth of the pandemic of the disease caused by the human immunodeficiency virus (HIV) in the world, the absence reliable means prevention and treatment allows us to classify this problem as one of the most acute. Until 1996, Russia was one of the countries with a low level of HIV infection. Since 1996, the incidence of this infection began to increase sharply. The sharp increase is mainly due to the infection of drug users. The safety and quality of food products and food raw materials is one of the main factors determining the health of the population and the preservation of its gene pool. More than 5% of products do not meet hygienic requirements for the content of antibiotics.
2.3 Causes of infectious diseases and their characteristics.
No matter how significant the achievements of modern medicine in the study of various infectious diseases, in our time there are a number of potentially dangerous infections that can cause significant harm to the human body, and, by and large, are fatal to it. Today, doctors know about 1,200 different infections, which are dangerous to one degree or another, since not all of them have been fully studied and not all of them have a cure. There are infectious diseases, the causes of which are not entirely clear, and treatment is complicated by the fact that cures for the disease have not yet been created.
A characteristic feature of all infectious diseases is the incubation period - the period between the time of infection and the appearance of the first signs. Depending on what type of pathogen occurred, as well as on how the infection occurred, the duration of the incubation period may vary. From the moment of infection to the first symptoms, several hours and even, in rare cases, several years can pass.
Pathogenic microorganisms can enter the body in different ways, and for each species these methods can be different. The mechanisms of transmission may also differ between different types of infections, and the ability of the pathogen to exist in the external environment outside the infected organism plays a major role here. It is during the period when pathogenic organisms are in the external environment that they are most vulnerable; many of them die from drying out, exposure to sunlight, etc. At the same time, being outside the source of infection, infectious agents pose a danger to healthy people, especially since many of them microorganisms retain the ability to survive in a favorable external environment for a long time.
2.4 Routes of transmission of infection.
Infectious diseases can be transmitted in different ways, the causes of the disease in a person can be different, treatment of infection involves a mandatory search for the source of infection, clarification of the circumstances of the onset of the disease, in order to stop its further spread.
1. Transmission of infection through the outer skin. In this case, the infectious agent is transmitted through the touch of a sick person with a healthy person. Contact can be direct or indirect (through household items).
2. Fecal-oralmode of transmission: the pathogen is excreted along with the feces of an infected person, and transmission to a healthy person occurs through the mouth.
3. Water mechanismtransmission occurs through dirty water.
4. Air routeoccurs in infections, mainly of the respiratory tract. Some pathogens are transmitted with droplets of mucus, while other microbes enter the body with dust particles.
5. Among other things, infectious agents can be transmitted through insects; sometimes this transmission mechanism is called transmission .
2. 5 Nosogeography of infectious diseases.
The geography of diseases is largely determined by the influence of natural factors (climate, presence or absence in water, soil, and, consequently, in food products of some chemical elements etc.) and social (material living conditions, cultural level of the population, traditional type of nutrition, etc.) factors. This geography is called nosogeography. It is closely related to epidemiological geography (i.e., the geography of infectious diseases), microbiology, hygiene, pathology, etc.
It has long been noted that many human diseases occur only in certain parts globe: for example, yellow fever - in South American countries and Africa, cholera - most often in India and adjacent Asian countries, leishmaniasis - mainly in arid countries, etc. And in conditions former USSR many diseases had a fairly clear regional character. Thus, Ufa was “recognizable” by cholecystitis; in Tagil and Taganrog, diseases of the upper respiratory tract were more common; Kineshma was characterized by chronic pyelonephritis; in Salavat they suffered from chronic and rheumatic heart diseases; V major cities more noted gastrointestinal diseases; in port cities - venereal, etc. Not only cities, but also entire regions of the former Union were “recognizable” by characteristic diseases. Vitamin deficiencies are common in the Far North; Far East dangerous tick-borne encephalitis; in Ukraine and Belarus there is an increased incidence of bronchial asthma; in Dagestan were most often recorded iron deficiency anemia; in Karelia, Kazakhstan, Buryatia, Astrakhan and Murmansk regions, esophageal cancer predominates, etc.
2.6 Classification of infectious diseases.
Intestinal infections
- infections skin and mucous membranes
- respiratory tract infections
- blood infections.
Each group has an individual method of transmission of infection and its own routes of transmission of microorganisms.
Causative agent of intestinal infections (dysentery, cholera, typhoid fever, infectious hepatitis, botulism) is released into the external environment with feces and vomit. The causative agent of intestinal infections enters the bodies of healthy people with contaminated water and food, with unwashed hands or with the help of flies.
Causative agent of respiratory tract infections (whooping cough, diphtheria, measles, ARVI) is released into the external environment when coughing, when sputum is discharged, when sneezing and simply with exhaled air. The infection enters the bodies of healthy people with contaminated air and dust.
Influenza is the most common infectious disease. It is caused by different strains of the influenza virus, and since there is a different strain almost every year, an effective vaccine cannot be developed. The source of infection is a sick person. The route of transmission is airborne. From the moment of infection until symptoms of the disease appear, 1-3 days pass.
Influenza is manifested by an increase in temperature or fever with chills, headache, a feeling of general weakness, and often joint and muscle pain. At the same time, and even somewhat earlier, a characteristic feeling of sore throat, a dry cough, accompanied by pain in the trachea, is noted. This is usually accompanied by burning and redness of the conjunctiva of the eyes; Most patients develop a runny nose.
Diagnosing influenza is quite simple. The number of diseases in Poland is gradually increasing. The annual number of cases in Poland ranges from 1.5 to 6 million people.
The flu is often taken lightly, and this is wrong. Influenza can be very dangerous for people who have pre-existing illnesses or are regularly taking medications, as well as for older people. The most common complication is pneumonia. Young children and older people should be seen by a doctor if they have the flu.
Causative agent of blood infections (leishmaniasis, phlebotomy fever, malaria, encephalitis (tick-borne and mosquito-borne), plague, fever, typhus) lives in the blood of arthropods. A healthy person becomes infected through the bites of arthropods: ticks, mosquitoes, horse flies, fleas, lice, flies, midges and biting midges.
Causative agent of infections of the skin and mucous membranes
(venereal diseases, anthrax, erysipelas, scabies, trachoma) enters the body of a healthy person through wounds and other damage to the skin. And also through mucous membranes. A healthy person becomes infected with these infections through sexual contact with sick people, through household contact (use of towels and bedding, linen), through salivation and bites of infected animals, through abrasions and scratches, and contact with contaminated soil on damaged areas of the skin.
If an infectious disease is detected, the patient must be immediately isolated. It is necessary to identify all people who were in contact with the patient and, if possible, isolate them during the incubation period of the disease. Such measures are being taken to prevent an epidemic of a dangerous infection.
Because In our city, a large number of hepatitis A diseases have been identified, I think it is necessary to give more detailed description this disease and talk about its prevention.
Viral hepatitis A is a human infectious disease characterized by predominant liver damage, in typical cases manifested by general malaise, increased fatigue, anorexia, nausea, vomiting, sometimes jaundice (dark urine, discolored stool, yellowing of the sclera and skin). The incubation period ranges from 7 to 50 days, most often ranging from 25 to 30 days. Transmission factors include water, food (usually uncooked) and household items. The source of infection is a sick person. The route of infection with this disease is the same as for intestinal infections. It should be noted that two circumstances contribute to the widespread spread of hepatitis A.
Firstly, The hepatitis A virus is much more resistant to sunlight, disinfectants and boiling than pathogens of other intestinal infections, so it can persist for a long time in the external environment.
Secondly, The patient is most dangerous to those around him before he develops jaundice. During this period, it releases the largest number of viruses, although either dyspepsia or flu-like symptoms come to the fore: fever, headache, lethargy, runny nose, cough. Patients with anicteric and asymptomatic formspose the greatest danger to others. Thus, an apparently healthy person can serve as a source of danger to others. The highest concentration of the pathogen in the feces of the source of infection is observed in the last 7-10 days of the incubation period and in the first days of the disease.
Prevention of hepatitis A:
1. Compliance with personal hygiene rules.
2. Control over the quality of drinking water and food.
3. Immunoprophylaxis of hepatitis A includes the administration of a vaccine or immunoglobulin.
No less acute problem our city remains an infectious disease AIDS-acquired immunodeficiency syndrome.
In 1981, a new unknown disease was reported in the United States, which often resulted in death. As a result of the research, it was found that this disease is of a viral nature, it was called Immunodeficiency Syndrome (AIDS). The virus that causes the disease is called HIV (Human Immunodeficiency Virus). This virus infects those cells of the human body that are designed to counteract virus system, this virus penetrates into lymphocytes - blood cells. On the screen you see –“Healthy lymphocyte cell.”
The HIV virus penetrates lymphocytes – blood cells that provide immune protection to the human body, multiply in them and cause their death.New viruses infect new cells , but before the number of lymphocytes decreases to such an extent that immunodeficiency develops, years (usually 4–6 years) may pass, during which the virus carrier is a source of infection for other people.Absence immune defense in a sick person leads to greater susceptibility to various infections.
Symptoms of the disease:
secondary infections of a bacterial, fungal, viral nature (enlarged lymph glands, pneumonia, prolonged diarrhea, fever, weight loss)
cancer
damage to the central nervous system (weakening of memory, intelligence, impaired coordination of movements).
Routes of HIV transmission
through blood and blood products,
from mother to newborn child.
AIDS prevention
use of disposable syringes and needles.
use personal hygiene items.
disinfection of manicure tools.
avoid acupuncture treatment outside of medical institutions,
Avoid tattoos and earlobe piercings with non-sterile instruments.
III . Conclusion. Prevention of infectious diseases.
Infectious diseases are natural phenomena in the history of mankind, which are formed and reborn along with it. Some infections replace others, and with them come new problems. prevention . Today, the incidence of infectious diseases remains very high, and the prevalence covers the whole world. Tens of millions of infectious diseases are reported every year.
Modern medicines provide treatment for the patient, taking into account his individual characteristics and the specific course of the disease. Proper patient care and balanced nutrition are of great importance. To avoid infection, you must follow and applypreventive measures .
prevention of intestinal infectious diseases When this infection is detected, patients are isolated and treated. You must follow the rules for storing, preparing and transporting food. Before eating and after visiting the toilet, you should always wash your hands with soap. Thoroughly wash vegetables and fruits, boil milk and drink only boiled water.
prevention of blood infectious diseases , when this infection is detected, the sick are isolated and monitored
prevention of infectious diseases of the external integument When this infection is detected, the patient is isolated and treated. Hygienic conditions must be strictly observed. For prevention purposes, preventive vaccinations are used.
Today, there are a number of infections that only vaccination can protect against. Why is it necessary to have preventive vaccinations? Vaccinationimmunoprophylaxis of infectious diseases , creates active immunity to infections. Repeated vaccinations should be done to maintain reliable immunity. Prevention of childhood infectious diseases is carried out primarily with weakened and often ill children, since they are more at risk of contracting infectious diseases that occur in severe forms.
Before you do preventive vaccination, you need to see a therapist or pediatrician and make sure that there are no contraindications. Getting vaccinated will guarantee that you will not catch any infection.
How to prevent an infectious disease?
Every person should know that if signs of an infectious disease are detected, they should urgently seek medical help. In no case should it be concealed; an outbreak of an infectious disease can harm both relatives and the entire team at work. When a patient is isolated, he will cease to be a source of infection in the team. The most reliable way to protect yourself from an infectious disease isprevention of infectious diseases , which is timely immunization. It is necessary to increase the body's characteristic resistance to various pathogens, i.e., influence the immune system. In order to prevent certain infectious diseases, it is carried out prophylactic use chemotherapy drugs and antibiotics.
About the prevention of ARVI and influenza
High temperature, chills and headache are indispensable companions of ARVI and influenza. But even at the most dangerous period you can avoid colds. To prevent colds from overpowering you and your children, follow simple preventive measures.
One of the most common and accessible means of flu prevention is a mask. It should be worn by both the sick person and those who come into contact with him.
Remember that the infection is easily transmitted through dirty hands, so during epidemic periods it is better to avoid shaking hands. You should also wash your hands frequently, especially when you are sick or caring for someone sick.
During the epidemic, it is recommended to avoid traveling by city bus. public transport and don't visit.
Can be taken ascorbic acid and multivitamins. Vitamin C is taken orally 0.5–1 g 1–2 times a day. A large amount of vitamin C is also found in sauerkraut juice, as well as in kiwi and citrus fruits - lemons, tangerines, oranges, grapefruits.
For prevention during flu and cold epidemics, you need to eat garlic, 2-3 cloves daily. It is enough to chew a clove of garlic for a few minutes to completely cleanse your mouth of bacteria. Onions also have a positive effect.
The daily presence of fresh vegetables and fruits in your diet will improve your overall immunity.
Don’t forget about the toilet of your nose - wash the anterior sections of your nose with soap 2 times a day. In this case, foreign structures that enter the nasal cavity with inhaled air are mechanically removed.
Are you hypothermic? Take a warm foot bath with mustard (5-10 minutes) and put on wool socks.
You need to walk as much as possible. It is almost impossible to get infected with ARVI and flu in the fresh air!
At the first symptoms of illness, stay home and call a medical professional!!!
The suspension of the educational process in schools in Saratov made it possible to reduce the incidence of ARVI and influenza among schoolchildren by 25%, but the incidence rate among children 7–14 years old remains above the estimated epidemic threshold by 91.9%. In this regard, it was decided to extend the extraordinary holidays for schoolchildren until February 23, 2013.
Theoretical and practical significance completed work.
I recommend using this work on classroom hours for the purpose of preventing infectious diseases, in biology lessons when studying the topic “Immunity”. Since an outbreak of Hepatitis A was detected on the territory of the BIS, cases of HIV-infected people were identified, and epidemics of acute respiratory viral infections and influenza were registered, I gave a description of these diseases and their prevention.
Our health is in our hands!
Subject: "Infectious diseases and their prevention."
I. Introduction. Relevance of the problem…………………………………………………….2
II. Main part.
2.1. What are infectious diseases?................................................. ........................3
2.2 Sanitary and epidemiological situation in the Russian Federation and in the city of Balakovo………………………………………………………………………………………...3
2.3. Causes and characteristics of infectious diseases……………………………..4
2.4. Routes of transmission………………………………………………………. 5
2.5. Nosogeography of infectious diseases………………………………………………………5
2.6. Classification of infectious diseases……………………………………………………….6
III. Conclusion.
Prevention of infectious diseases……………………………………………………...8
IV.Bibliography…………………………………………………………………………………
Objectives:
Familiarize yourself with the main types of infectious diseases.
Tasks:
1. Identify mechanisms of transmission of infectious diseases.
2.Study measures to prevent common infectious diseases.
I.Introduction. Relevance of the problem.
Even in ancient times, various infections terrified humanity; epidemics of various diseases devastated cities and countries, killing millions of people. Entire nations were on the verge of extinction; the so-called “pestilence” was considered one of the worst punishments in the whole world, and measures to combat it were sometimes decisive and merciless. Sometimes huge territories with all people and property were burned out in order to prevent the spread of the deadly disease further. In the modern world, medicine has learned to fight and prevent many of those terrible infections that in the Middle Ages became the scourge of society, which became the reason for some of the euphoria that gripped humanity in the mid-twentieth century. But the joy of success in the fight against previous diseases was somewhat premature, since they were replaced and continue to be replaced by new infectious diseases that could potentially destroy a significant number of people.
Throughout recorded history, the greatest scourge for humanity has been plague, smallpox, cholera and yellow fever, which have claimed the lives of large numbers of people.
However, the battle against infectious agents is still ongoing and the only infectious disease successfully eradicated in the world is smallpox.
Elimination of other diseases, such as tetanus, measles, whooping cough, diphtheria and polio, for which effective immunization is quite feasible on a global scale, has now been achieved by more than 90%.
High immigration from third world countries has led to a sharp increase in the number of people suffering from infectious diseases in industrialized countries.
While humanity has managed to learn to control old epidemics, new ones have emerged. It should be noted that there is an ongoing epidemic of human immunodeficiency virus (HIV) infection, which is accompanied by devastating consequences not only in Africa and Asia, but also in Europe and North America.
Despite the improvement of living conditions in economically developed countries, the widespread practice of vaccinations and the availability of effective antibiotics, infectious diseases still occupy a significant place in the structure of human morbidity and mortality and are second only to diseases of the cardiovascular system and malignant oncological diseases. Most deaths among children are infectious diseases of the respiratory system and intestines caused by viruses and bacteria.
On the territory of the Balakovo municipal district since August 2012. there is a deterioration in the epidemiological situation regarding the incidence of acute viral hepatitis A
Hepatitis A is a widespread infectious disease caused by the hepatitis A virus. Periodic increases in incidence are characteristic, especially in the summer and autumn months. Infectious diseases, as in previous years, continue to occupy one of the leading places among human diseases. The problems of viral hepatitis and acute intestinal infections remain relevant. Long-forgotten diphtheria has returned from past years, tuberculosis has become widespread, new infections caused by herpes viruses, Borrelia, chlamydia, etc., AIDS poses a threat to humanity. In the context of socio-economic changes that led to the stratification of society and the emergence of a large number of socially unprotected people, many infectious diseases became severe, often fatal. Influenza and ARVI remain one of the most pressing medical and socio-economic problems, and an example of this is the epidemiological situation in our city and in the Saratov region in January - March of this year. I went to clinic No. 3 and took data on ARVI and influenza for the period from February 4th to 18th and found out that the number of people sick during this period was 6884 people, 3749 of them were children. I I chose the topic “Infectious diseases” because I think this problem is very important and difficult to solve. After looking through and reading a large amount of literature about infectious diseases, I decided to tell you about them, as well as their prevention.
II. Main part.
2.1What are infectious diseases?
Infectious diseases- this is a group of diseases caused by the penetration of pathogenic (disease-causing) microorganisms into the body. In order for the pathogenic microbe to cause infectious disease, he must have virulence, that is, the ability to overcome the body’s resistance and exhibit toxic effects. Some pathogenic agents cause poisoning of the body with exotoxins released by them in the process of life (tetanus, diphtheria), others release toxins (endotoxins) during the destruction of their bodies (cholera, typhoid fever).
At the end of the 18th century, the French scientist Louis Pasteur refuted the theory of spontaneous generation of microorganisms. He isolated the causative agents of anthrax, rubella, and rabies, and proposed a method for disinfecting food products (pasteurization). L. Pasteur is rightfully considered the founder of modern microbiology and immunology.
Hippocrates also drew attention to the fact that diseases are preceded by certain environmental conditions and the state of people’s health. Infectious diseases can occur when three components are present:
source of infectious agents (infected person or animal);
a factor that ensures the transmission of pathogens from an infected organism to a healthy one;
people susceptible to infection.
2.2Sanitary and epidemiological situation in the Russian Federation and in the city of Balakovo.
The 20th century gave rise to unjustified optimism that infectious diseases would soon be eliminated. However, the events of recent decades have shown that infections such as tuberculosis and malaria, which are becoming the main cause of mortality, have sharply intensified in the world; both in Russia and in other countries, diphtheria is re-emerging. The epidemiological situation that has developed in recent years remains tense. Every year from 33 to 44 million cases of infectious diseases are registered in the Russian Federation. Influenza and ARVI remain one of the most pressing medical and socio-economic problems. In the period from January to March 2013, in the Saratov region and on the territory of the BIS, an excess of the long-term average incidence of ARVI and influenza was observed by 35%.
Viral hepatitis continues to be a serious health problem, causing damage to both public health and the country's economy. On the territory of the Balakovo municipal district since August 2012. there is a deterioration in the epidemiological situation regarding the incidence of acute viral hepatitis A
Hepatitis A is a widespread infectious disease caused by the hepatitis A virus. Periodic increases in incidence are characteristic, especially in the summer and autumn months. In the territory of the BIS for 8 months of 2012, 46 cases of hepatitis A were registered, which is 4.3 higher than the incidence rate of hepatitis A for the same period last year. According to operational data, the situation regarding the incidence of this infection has become more complicated. As of October 18, 2012, another 22 cases were identified. Every day 2-3 new cases of this disease are registered.
The situation is especially difficult with regard to socially determined diseases. Since 1992, the incidence of tuberculosis began to increase in the country with an annual increase of 10-15%.
Based on the coverage of the population with preventive examinations for tuberculosis at the end of 2012. the figure was 75.5%. To combat this terrible disease, federal and regional programs were adopted, which made it possible to significantly reduce the prevalence of this disease.
The incidence of tuberculosis (in the Saratov region - 61.5 cases per 100 thousand population, in Balakovo and Balakovo region 55.9. Compared to 2011, we have seen an increase in incidence.
The rapid growth of the pandemic of the disease caused by the human immunodeficiency virus (HIV) in the world, the lack of reliable means of prevention and treatment allows us to classify this problem as one of the most acute. Until 1996, Russia was one of the countries with a low level of HIV infection. Since 1996, the incidence of this infection began to increase sharply. The sharp increase is mainly due to the infection of drug users. The safety and quality of food products and food raw materials is one of the main factors determining the health of the population and the preservation of its gene pool. More than 5% of products do not meet hygienic requirements for the content of antibiotics.
2.3 Causes of infectious diseases and their characteristics.
No matter how significant the achievements of modern medicine in the study of various infectious diseases, in our time there are a number of potentially dangerous infections that can cause significant harm to the human body, and, by and large, are fatal to it. Today, doctors know about 1,200 different infections, which are dangerous to one degree or another, since not all of them have been fully studied and not all of them have a cure. There are infectious diseases, the causes of which are not entirely clear, and treatment is complicated by the fact that cures for the disease have not yet been created.
A characteristic feature of all infectious diseases is the incubation period - the period between the time of infection and the appearance of the first signs. Depending on what type of pathogen occurred, as well as on how the infection occurred, the duration of the incubation period may vary. From the moment of infection to the first symptoms, several hours and even, in rare cases, several years can pass.
Pathogenic microorganisms can enter the body in different ways, and for each species these methods can be different. Transmission mechanisms may also vary between different types of infections, with the ability of the pathogen to exist in the external environment outside the infected organism playing a major role here. It is during the period when pathogenic organisms are in the external environment that they are most vulnerable; many of them die from drying out, exposure to sunlight, etc. At the same time, being outside the source of infection, infectious agents pose a danger to healthy people, especially since many of them microorganisms retain the ability to survive in a favorable external environment for a long time.
2.4 Routes of transmission of infection.
Infectious diseases can be transmitted in different ways, the causes of the disease in a person can be different, treatment of infection involves a mandatory search for the source of infection, clarification of the circumstances of the onset of the disease, in order to stop its further spread.
1. Transmission of infection through the outer covering or contact route. In this case, the infectious agent is transmitted through the touch of a sick person with a healthy person. Contact can be direct or indirect (through household items).
2. Fecal-oral transmission: the pathogen is excreted along with the feces of an infected person, and transmission to a healthy person occurs through the mouth.
3. Water transmission mechanism occurs through dirty water.
4. The air route occurs in infections, mainly of the respiratory tract. Some pathogens are transmitted with droplets of mucus, while other microbes enter the body with dust particles.
5. Among other things, infectious agents can be transmitted through insects; sometimes this transmission mechanism is called transmissible.
2. 5 Nosogeography of infectious diseases.
The geography of diseases is largely determined by the influence of natural (climate, presence or absence of certain chemical elements in water, soil, and, consequently, in food products, etc.) and social (material living conditions, cultural level of the population, traditional type of nutrition, etc.) d.) factors. This geography is called nosogeography. It is closely related to epidemiological geography (i.e., the geography of infectious diseases), microbiology, hygiene, pathology, etc.
It has long been noted that many human diseases are found only in certain parts of the globe: for example, yellow fever - in the countries of South America and Africa, cholera - most often in India and adjacent Asian countries, leishmaniasis - mainly in arid countries, etc. etc. And in the conditions of the former USSR, many diseases had a fairly clear regional character. Thus, Ufa was “recognizable” by cholecystitis; in Tagil and Taganrog, diseases of the upper respiratory tract were more common; Kineshma was characterized by chronic pyelonephritis; in Salavat they suffered from chronic and rheumatic heart diseases; in large cities there are more gastrointestinal diseases; in port cities - venereal diseases, etc. Not only cities, but also entire regions of the former Union were “recognizable” by their characteristic diseases. Vitamin deficiencies are common in the Far North; The Far East is dangerous with tick-borne encephalitis; in Ukraine and Belarus there is an increased incidence of bronchial asthma; in Dagestan, iron deficiency anemia was most often recorded; in Karelia, Kazakhstan, Buryatia, Astrakhan and Murmansk regions, esophageal cancer predominates, etc.
Intestinal infections
- infections of the skin and mucous membranes
- respiratory tract infections
- blood infections.
Each group has an individual method of transmission of infection and its own routes of transmission of microorganisms.
Causative agent of intestinal infections (dysentery, cholera, typhoid fever, infectious hepatitis, botulism) is released into the external environment with feces and vomit. The causative agent of intestinal infections enters the bodies of healthy people with contaminated water and food, with unwashed hands or with the help of flies.
Causative agent of respiratory tract infections (whooping cough, diphtheria, measles, ARVI) is released into the external environment when coughing, when sputum is discharged, when sneezing and simply with exhaled air. The infection enters the bodies of healthy people with contaminated air and dust.
Influenza is the most common infectious disease. It is caused by different strains of the influenza virus, and since there is a different strain almost every year, an effective vaccine cannot be developed. The source of infection is a sick person. The route of transmission is airborne. From the moment of infection until symptoms of the disease appear, 1-3 days pass.
Influenza is manifested by an increase in temperature or fever with chills, headache, a feeling of general weakness, and often joint and muscle pain. At the same time, and even somewhat earlier, a characteristic feeling of sore throat, a dry cough, accompanied by pain in the trachea, is noted. This is usually accompanied by burning and redness of the conjunctiva of the eyes; Most patients develop a runny nose.
Diagnosing influenza is quite simple. The number of diseases in Poland is gradually increasing. The annual number of cases in Poland ranges from 1.5 to 6 million people.
The flu is often taken lightly, and this is wrong. Influenza can be very dangerous for people who have pre-existing illnesses or are regularly taking medications, as well as for older people. The most common complication is pneumonia. Young children and older people should be seen by a doctor if they have the flu.
Causative agent of blood infections (leishmaniasis, phlebotomy fever, malaria, encephalitis (tick-borne and mosquito-borne), plague, fever, typhus) lives in the blood of arthropods. A healthy person becomes infected through the bites of arthropods: ticks, mosquitoes, horse flies, fleas, lice, flies, midges and biting midges.
Causative agent of infections of the skin and mucous membranes
(venereal diseases, anthrax, erysipelas, scabies, trachoma) enters the body of a healthy person through wounds and other damage to the skin. And also through mucous membranes. A healthy person becomes infected with these infections through sexual contact with sick people, through household contact (use of towels and bedding, linen), through salivation and bites of infected animals, through abrasions and scratches, and contact with contaminated soil on damaged areas of the skin.
If an infectious disease is detected, the patient must be immediately isolated. It is necessary to identify all people who were in contact with the patient and, if possible, isolate them during the incubation period of the disease. Such measures are being taken to prevent an epidemic of a dangerous infection.
Because A large number of hepatitis A diseases have been identified in our city, I think it is necessary to give a more detailed description of this disease and talk about its prevention.
Viral hepatitis A is a human infectious disease characterized by predominant liver damage, in typical cases manifested by general malaise, increased fatigue, anorexia, nausea, vomiting, and sometimes jaundice (dark urine, discolored stool, yellowing of the sclera and skin). The incubation period ranges from 7 to 50 days, most often ranging from 25 to 30 days. Transmission factors include water, food (usually uncooked) and household items. The source of infection is a sick person. The route of infection with this disease is the same as for intestinal infections. It should be noted that two circumstances contribute to the widespread spread of hepatitis A.
Firstly, The hepatitis A virus is much more resistant to sunlight, disinfectants and boiling than pathogens of other intestinal infections, so it can persist for a long time in the external environment.
Secondly, The patient is most dangerous to those around him before he develops jaundice. During this period, it releases the largest number of viruses, although either dyspepsia or flu-like symptoms come to the fore: fever, headache, lethargy, runny nose, cough. Patients with anicteric and asymptomatic forms pose the greatest danger to others. Thus, an apparently healthy person can serve as a source of danger to others. The highest concentration of the pathogen in the feces of the source of infection is observed in the last 7-10 days of the incubation period and in the first days of the disease.
Prevention of hepatitis A:
1. Compliance with personal hygiene rules.
2. Control over the quality of drinking water and food.
3. Immunoprophylaxis of hepatitis A includes the administration of a vaccine or immunoglobulin.
An equally pressing problem in our city remains the infectious disease AIDS. acquired immunodeficiency syndrome.
In 1981, a new unknown disease was reported in the United States, which often resulted in death. As a result of the research, it was found that this disease is of a viral nature, it was called Immunodeficiency Syndrome (AIDS). The virus that causes the disease is called HIV (Human Immunodeficiency Virus). This virus infects those cells of the human body that are designed to counteract the viral system; this virus penetrates into lymphocytes - blood cells. On the screen you see –“ Healthy lymphocyte cell.”
The HIV virus penetrates lymphocytes– blood cells that provide immune protection to the human body, multiply in them and cause their death. New viruses infect new cells , but before the number of lymphocytes decreases to such an extent that immunodeficiency develops, years (usually 4–6 years) may pass, during which the virus carrier is a source of infection for other people. The lack of immune defense in a sick person leads to greater susceptibility to various infections.
Symptoms of the disease:
secondary infections of a bacterial, fungal, viral nature (enlarged lymph glands, pneumonia, prolonged diarrhea, fever, weight loss are observed)
cancer
damage to the central nervous system (weakening of memory, intelligence, impaired coordination of movements).
sexual tract,
through blood and blood products,
from mother to newborn child.
use of disposable syringes and needles.
use personal hygiene items.
disinfection of manicure tools.
avoid acupuncture treatment outside of medical institutions,
Avoid tattoos and earlobe piercings with non-sterile instruments.
Infectious diseases are natural phenomena in the history of mankind, which are formed and reborn along with it. Some infections replace others, and with them come new problems of their prevention. Today, the incidence of infectious diseases remains very high, and the prevalence covers the whole world. Tens of millions of infectious diseases are reported every year.
Modern medicines provide treatment for the patient, taking into account his individual characteristics and the specific course of the disease. Proper patient care and balanced nutrition are of great importance. To avoid infection, you must follow and apply preventive measures.
prevention of intestinal infectious diseases When this infection is detected, patients are isolated and treated. You must follow the rules for storing, preparing and transporting food. Before eating and after visiting the toilet, you should always wash your hands with soap. Thoroughly wash vegetables and fruits, boil milk and drink only boiled water.
prevention of blood infectious diseases, when this infection is detected, the sick are isolated and monitored
prevention of infectious diseases of the external integument When this infection is detected, the patient is isolated and treated. Hygienic conditions must be strictly observed. For prevention purposes, preventive vaccinations are used.
Before getting a preventive vaccination, you need to see a therapist or pediatrician to make sure that there are no contraindications. Getting vaccinated will guarantee that you will not catch any infection.
How to prevent an infectious disease?
Every person should know that if signs of an infectious disease are detected, they should urgently seek medical help. In no case should it be concealed; an outbreak of an infectious disease can harm both relatives and the entire team at work. When a patient is isolated, he will cease to be a source of infection in the team. The most reliable way to protect yourself from an infectious disease is prevention of infectious diseases, which is timely immunization. It is necessary to increase the body's characteristic resistance to various pathogens, i.e., influence the immune system. In order to prevent certain infectious diseases, the prophylactic use of chemotherapy and antibiotics is carried out.
About the prevention of ARVI and influenza
High temperature, chills and headache are indispensable companions of ARVI and influenza. But even in the most dangerous period, you can avoid colds. To prevent colds from overpowering you and your children, follow simple preventive measures.
One of the most common and accessible means of flu prevention is a mask. It should be worn by both the sick person and those who come into contact with him.
Remember that the infection is easily transmitted through dirty hands, so during epidemic periods it is better to avoid shaking hands. You should also wash your hands frequently, especially when you are sick or caring for someone sick.
During the epidemic, it is recommended to avoid traveling on public transport and not visiting people.
You can take ascorbic acid and multivitamins. Vitamin C is taken orally 0.5–1 g 1–2 times a day. A large amount of vitamin C is also found in sauerkraut juice, as well as in kiwi and citrus fruits - lemons, tangerines, oranges, grapefruits.
For prevention during flu and cold epidemics, you need to eat garlic, 2-3 cloves daily. It is enough to chew a clove of garlic for a few minutes to completely cleanse your mouth of bacteria. Onions also have a positive effect.
The daily presence of fresh vegetables and fruits in your diet will improve your overall immunity.
Don’t forget about the toilet of your nose - wash the anterior sections of your nose with soap 2 times a day. In this case, foreign structures that enter the nasal cavity with inhaled air are mechanically removed.
Are you hypothermic? Take a warm foot bath with mustard (5-10 minutes) and put on wool socks.
You need to walk as much as possible. It is almost impossible to get infected with ARVI and flu in the fresh air!
At the first symptoms of illness, stay home and call a medical professional!!!
The suspension of the educational process in schools in Saratov made it possible to reduce the incidence of ARVI and influenza among schoolchildren by 25%, but the incidence rate among children 7–14 years old remains above the estimated epidemic threshold by 91.9%. In this regard, it was decided to extend the extraordinary holidays for schoolchildren until February 23, 2013.
Theoretical and practical significance of the work performed.
I recommend using this work in classroom hours for the prevention of infectious diseases, in biology lessons when studying the topic “Immunity”. Since an outbreak of Hepatitis A was detected on the territory of the BIS, cases of HIV-infected people were identified, and epidemics of acute respiratory viral infections and influenza were registered, I gave a description of these diseases and their prevention.
Our health is in our hands!
Bibliography
1. V.V. Gaevaya “The natural environment is a source of infectious diseases”
2. V.N. Motnink “How to protect yourself from diseases”
3. E.V.Kriksunov, V.V.Pasechnik “Ecology 9kl”
4. I.B. Filatova “Infectious diseases and their prevention”
5. I.K. Toporov “Fundamentals of life safety.”
N.G. Ivanova “Man and his health”
Internet resources
www.biologiyavo.ru
www.epidemiolog.ru
www.valoologiya.ru
www.profinfect.ru
| Major infectious diseases. Classification, routes of transmission and prevention
Basics of life safety
10th grade
Lesson 21
Major infectious diseases. Classification, routes of transmission and prevention
 |
 |
|
A person is surrounded by microorganisms throughout his life. They are found in air, water, soil, and are deposited on all objects, including food products. Microbes live and multiply on the skin, in the mouth and nose, on the mucous membrane of the upper respiratory tract, in the intestines, especially in the thick part.
Microorganisms play an important role in life not only of humans, but of the entire organic world of the Earth. For example, they purify soil and water from dead bodies through putrefaction, fermentation, decomposition. At the same time, when they get into wounds, they can cause suppuration, and when they penetrate into the internal environment of the human body, they can cause an infectious disease.
Classification of microorganisms and infectious diseases
The entire variety of microorganisms known to modern science from the point of view of their influence on the human body is divided into three types, shown in Diagram 25.
Our country has adopted a classification of infectious diseases, which is based on the mechanism of transmission of the infectious principle and its localization in the body. According to this classification, all infectious diseases are divided into five groups (Table 3).
This or that infectious disease is associated with the penetration of a certain microorganism into the body. For example, the pertussis bacillus causes only whooping cough, the dysentery bacillus causes dysentery, the diphtheria bacillus causes diphtheria, and vibrio cholerae causes cholera.
The emergence and spread of infectious diseases Infectious diseases differ from all others in that they spread quite quickly among people. The massive spread of an infectious disease, significantly exceeding the normal incidence rate, is called an epidemic. If it covers the territory of an entire state or several countries, it is called a pandemic.
To prevent an infectious disease, you need to know how it occurs and how it spreads among people.
All infectious diseases are contagious and are transmitted from a sick person or sick animal to a healthy one. But a healthy person can also serve as a source of infectious disease. After past illness For still unclear reasons, a paradoxical situation arises. The person recovers and feels well, but the pathogenic microbe continues to be present in his body. An amazing union arises when one organism does not notice the other. This can go on for as long as you like. This is not dangerous for the body itself, but it is extremely dangerous for others, since the pathogenic microbe remains unharmed for a long time and is released into the external environment. This phenomenon is called bacilli carriage, and humans are called bacilli carriers.
Currently known at least five ways of transmission(Fig. 44):
All are transmitted by the fecal-oral route intestinal infections(“diseases of dirty hands”); a pathogenic microbe with feces, vomit of a sick person or a carrier of the bacilli gets onto food, water, dishes, and then through the mouth enters the gastrointestinal tract of a healthy person, causing disease (this is how, in particular, the spread of dysentery occurs);
all viral diseases of the upper respiratory tract, primarily influenza, are spread by airborne droplets: the virus with mucus, when sneezing or talking, enters the mucous membranes of the upper respiratory tract of a healthy person, who becomes infected and falls ill;
the liquid transmission route is typical for so-called blood infections; The carriers of this group of diseases are blood-sucking insects: fleas, lice, ticks, mosquitoes (plague and typhus are transmitted in this way);
wild and domestic animals serve as carriers of zoonotic infections; infection occurs through bites or through close contact with a sick animal (a typical representative of such diseases is rabies);
Most sexually transmitted diseases are contracted through contact or household contact through close contact between a healthy person and a sick person (the same way is also transmitted fungal diseases on the skin and nails).
Immunity
The difference between infectious diseases and all others is that the human body, after recovery, becomes immune to the re-introduction of the microorganism that caused the disease. This immunity is called immunity.
From a biological point of view, immunity is a way of protecting the internal constancy of the body from living bodies or substances that carry signs of genetically foreign information. These bodies and substances are called antigens. These include pathogenic microorganisms, cells and tissues of one’s own body that have become foreign, pollen, some plants, and some food products. In response to their introduction, the body begins to produce specific protein substances - antibodies.
Immunity is a set of protective and adaptive reactions of the human body that occur in response to a strictly defined antigenic stimulus in the form of an infectious disease agent or an artificially introduced antigen (vaccine or toxoid).
The body's immune response is the interaction of an antigen with an antibody. An important feature of immunity is the recognition and distinction of self from foreign.
Immunity is closely related to functional state organism and largely depends on environmental factors. Fasting, lack or absence of vitamins (vitaminosis), long-term illness, serious injuries, frequent stressful situations can contribute to a decrease in the body's resistance and the development of an infectious disease.
As a result of an infectious disease or artificial immunization (when an artificially weakened pathogen is introduced into the body), antibodies directed against a specific antigenic stimulus appear in a person’s blood. The number of antibodies is extremely high.
The organs of the human immune system include bone marrow, liver, spleen and lymphatic system.
Nature provides several types of immunity. Hereditary immunity is associated with a person’s species. It is inherited from parents to their child.
Next, a distinction is made between naturally acquired and artificially acquired immunity. The first is formed as a result of a previous illness. The second is formed actively or passively. During the active formation of artificial immunity, a vaccine is introduced into the body. It is weakened in some way, but retains all its harmful properties pathogen. Its introduction into the human body causes an infectious disease that occurs in mild form, but with a very pronounced immune reaction. With the passive formation of artificial immunity, ready-made antibodies (serum or gamma globulin) are introduced into the body.
Immunity formed in one way or another has a certain duration. For passive immunity, it ranges from several weeks to two to three months. Active immunity lasts longer. For example, smallpox vaccination (vaccination) provides a complete guarantee that a person will never get smallpox. The diphtheria or tetanus vaccine (when vaccinated three times) guarantees protection for 10 years. Then repeated vaccination (re-vaccination) is required. We must always remember that a single vaccination for some types of infectious diseases does not provide a lifetime guarantee.
Prevention of infectious diseases
To prevent the spread of infectious diseases, it is necessary to break the links connecting the elements of the general epidemiological chain and simultaneously influence each of its elements.
First element- a sick person or animal. If an infectious disease is suspected, a sick person is isolated and treated. A sick animal is treated differently: if it is an animal valuable to humans, it is treated, in all other cases it is euthanized. The situation is more complicated with bacilli carriers. This is quite healthy people for whom it would never even occur to them to see a doctor. Therefore, bacteria carriers must be actively identified. It is almost impossible to screen all people for bacilli carriage. Therefore, the survey is carried out selectively. It is subjected to those groups of people who are employed in catering units (buffets, canteens, restaurants) and in child care institutions.
Second element epidemiological chain - mechanisms of its transmission. To prevent the spread of infection, it is necessary to put a barrier on the routes of its transmission and destroy the mechanisms of its spread. To do this, you must follow the following rules in everyday life:
All food products must be cooked; plates, cups, forks, knives must be washed using preparations household chemicals, then rinse with plenty of water; fruits and vegetables must be thoroughly washed in running water; We must not forget about washing our hands before eating and after using the toilet;
at colds a simple and reliable way to prevent the disease is a regular three-layer gauze bandage, which can be used at work and at home; It is necessary to allocate individual dishes for the patient and wash them using disinfectants; the patient's handkerchiefs should be boiled and carefully ironed;
effective way preventing the spread of blood infections - destroying or repelling insects;
Zoonotic infections need to be prevented in several ways: valuable animals on animal farms must regularly undergo veterinary control; sick animals need to be treated; with a significant increase in the number of carriers and keepers of many infectious zoonotic diseases (these are mice, rats, etc.), they are deratized (destructed);
the reduction of diseases transmitted through contact and household methods can be achieved by increasing the hygienic culture of people, strengthening morality and ethics, stimulating public intolerance towards all manifestations of anticulture, violation of ethical norms and rules (an important element in this process is the education and upbringing of children and adolescents, instilling in them culture of health and healthy image life).
Third element in the general epidemiological chain has direct relation to you and me. Currently, the only reliable way to protect yourself from an infectious disease is known: promptly and carefully follow the recommendations of doctors for vaccination and revaccination.
Good nutrition, reasonable physical activity, and a healthy lifestyle also reduce the risk and likelihood of disease.
In all cases of an infectious disease occurring in a team, mandatory introduce a system of measures aimed at preventing the spread of the disease, the so-called quarantine. In a simplified form, this is a strict restriction of movement and contacts of people among whom the disease was detected. The duration of quarantine depends on the latent (incubation) period of the identified disease and is calculated from the moment of isolation of the last patient (the incubation period for cholera is 5 days, for dysentery - 7 days, for typhus - 21 days, etc.).
A comprehensive impact on all parts of the epidemiological process of any infectious disease prevents its spread. This requires the efforts of not only medical specialists, but also you and me. Getting vaccinated on time, maintaining a hygienic culture, a culture of health, and cultivating a hygienic worldview is in the interests of each of us.
External signs of an infectious disease
Most infectious diseases are accompanied by fever, chills, weakness throughout the body, and headache. Coughing, sneezing, copious discharge from the nose, sometimes vomiting, repeated loose stool, abdominal pain. Distinctive feature many infectious diseases - the appearance of a rash in the form of small reddish spots on the skin in various parts of the body. Sometimes a small bubble filled with clear liquid is visible in the center of the spot. As a rule, the diagnosis of an infectious disease is made on the basis of a bacteriological examination of the patient’s natural waste (smear from the throat, genital secretions, skin scrapings, smear from the rectum).
External signs of an infectious disease do not appear immediately from the moment the pathogenic microbe enters the body, but only after some time. The time from the introduction of a microorganism to the manifestation of the disease is called the incubation period. The duration of the incubation period for each infectious disease is different: from several hours to several weeks and even years.
Incubation or latent period does not mean that nothing happens in the body during this period. On the contrary, there is a fierce struggle between the pathogenic microbe and the body.
In the development of an infectious disease, several successively changing periods are traced: latent (incubation) period, onset of the disease, active manifestation of the disease, recovery. The duration of the periods varies and depends on the nature of the infection.
