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Question 28 The epidemic process
—A chain of continuous, consecutive, infectious conditions, from asymptomatic carriage to manifest diseases caused by a pathogen circulating in the collective. The epidemic process manifests itself in the form of epidemic foci, with one or more cases of illness or carriage.
The epidemic process is determined by the continuity of the interaction of its three constituent elements (links), namely:
1. The source of infectious disease pathogens;
2. the mechanism of transmission of pathogens;
3. The susceptibility of the population.
Switching off any of these links rigorously eliminates the epidemic process as a whole. This is one of the factors of transmission of infection formulated by L. V. Gromashevsky. The epidemic process proceeds continuously in time and space. At the same time, biological factors (the interaction of genotypically and phenotypically heterogeneous parasite and host populations) form the causes of the development of the epidemic process, while social and natural factors regulate the conditions for the development of the epidemic process. The epidemic process exists only with the simultaneous presence of causes and conditions.
The biological factor is the parasitic host-parasitic system, in which both interacting parties exhibit certain properties (the parasite is parasitism and pathogenicity, the host is susceptibility).
Social factors are a set of social conditions that contribute (or hinder) the manifestation of the epidemic process. Social factors include: social development;
social activity of the population; sanitary improvement of settlements.
Natural factors - a combination of natural conditions that contribute to or hinder the manifestation of the epidemic process. Natural factors include: biotic elements;
Biotic elements are components of wildlife. An example of the regulatory influence of biotic elements in zoonoses is a change in the intensity of the course of the epidemic process with a change in the number of rodents (intensity of the episodic process) with natural focal infections. In transmissible zoonoses, the number and migration of arthropod vectors has a regulatory effect on the intensity of the epidemic process.
Abiotic elements are climate and landscape-geographical conditions. For example, the closer to the equator, the higher the diversity of nosological forms of infectious diseases.
The mechanism of development of the epidemic process
In accordance with the first law of L.V. Gromashevsky, the epidemic process develops according to the triad:
source of pathogen;
transmission mechanism of the pathogen;
The source of the pathogen is an infected (infected) organism of a person, animal or plant, from which infection of susceptible people can occur ..
The transmission mechanism of an infectious agent is a way of moving a parasite from a sick organism to a healthy one, ensuring its existence as a biological species.
External integument (skin, some open mucous membranes - conjunctiva, external genitalia) Contact (direct and indirect contact)
Gastrointestinal tract Fecal-oral
Circulatory system (blood, endothelium of blood vessels) Transmissible (vector) - due to ectoparasites-arthropods
A transmission path is a specific set and sequence of transmission factors by which a transmission mechanism is implemented.
The aerosol pathogen transmission mechanism includes transmission paths:
airborne (meningococcal infection, acute respiratory viral infections; lifetime - minutes)
airborne dust (scarlet fever, tuberculosis; lifetime - day, week, month)
The fecal-oral transmission mechanism of the pathogen includes transmission routes:
water (transmission factor - water)
food (transmission factor - food)
contact-household (transmission factor - household items)
The transmission mechanism of the pathogen includes the transmission paths:
natural (contamination - the pathogen is excreted with the feces of the carrier; inoculation - the pathogen is introduced with saliva)
artificial (associated with medical manipulations: injection, associated with surgery, associated with diagnostic manipulation, transfusion, transplant)
Transmission factor is an environmental object by which the pathogen moves from a sick organism to a healthy one.
Transmission factors include: air, water, food, soil, household items, carriers (arthropods).
Transmission factors are divided into:
In addition, transmission factors can be divided into main and additional.
Phases of movement of the parasite:
discharge from an infected organism,
stay in the environment
incorporation into a susceptible organism.
Susceptibility - the ability of the host to suffer from diseases caused by pathogens, which is manifested by pathological and responsive protective specific (immunity) and non-specific (resistance) reactions.
Susceptibility is divided into:
individual (genotypic and phenotypic).
Manifestations of the epidemic process
The epidemic process is manifested by infection of the host with a pathogen followed by disease of the host or latent carriage of the parasite by the host, and at the population-species level - sporadic incidence, the presence of a natural or epidemic (epizootic, epiphytotic) foci of infection, outbreak, epidemic (epizootic, epiphytotism) or pandemic ( , panfithotia).
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Question 28 The epidemic process
- Epidemic Process Basics
The epidemic process is the occurrence and spread of infections among the population. For the emergence and continuous course of the epidemic process, the interaction of three factors is necessary: the source of the causative agents of the infection, the transmission mechanism of the infection, and the susceptible population. Shutting down any of these links interrupts the epidemic process. The biological basis of the epidemic
- Features of the epidemic process
An important feature of tissue helminthiases is the absence of their contagiousness, since a person does not participate in the natural circulation of parasites and becomes a biological dead end of invasion. Helminths that parasitize in the human body only at the larval stage do not turn into sexually mature individuals and cannot naturally stand out from the human body. They are not detected using
- The influence of various factors on the development of the epidemic process
The epidemic process of respiratory infections is constantly influenced by various social, natural and biological factors of human life. So, in schools and preschool institutions with well-established ventilation and heating, the incidence of acute respiratory infections (ceteris paribus) is always lower than among children living in similar rooms with
- Question 27 Infectious process
- a complex multicomponent process of the dynamic interaction of infectious pathogenic agents with macroorganism, characterized by the development of a complex of typical pathological reactions, systemic functional changes, hormonal status disorders, specific immunological defense mechanisms and non-specific resistance factors. Infectious process forms the basis
- Questions that arise - at the first stage of the breastfeeding process
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- Questions to identify the initial level of knowledge on the topic "Nursing process in diseases of the skin, navel, sepsis."
1) What anatomical and physiological features of the skin contribute to diseases in newborns? 2) What transient physiological conditions on the part of the skin do you know? 3) What elements of the rash are known to you? 4) What is pyoderma? 5) What factors can contribute to the occurrence of purulent-septic diseases? 6) What is aseptic and antiseptic? Give examples of antiseptics. 7) How
- Answers to questions to identify the initial level of knowledge on the topic "Nursing process in diseases of the skin, navel, sepsis."
1) A thin stratum corneum, rapidly desquamating epithelium, wealth of blood vessels, extreme vulnerability, rapid penetration of microbes, reduced protective function of the skin. 2) Physiological peeling, toxic erythema, physiological catarrh or erythema, physiological jaundice. 3) Spot, papule, vesicle, pustule. 4) Pustular inflammation of the skin. 5) Infectious diseases of the mother,
Training target: using diagnostic algorithms, be able to establish a diagnosis of mumps, determine the clinical form of the disease, complications and prescribe adequate treatment. Assignment for independent study of the topic. Using a textbook and lecture material to acquire the necessary basic knowledge, learn the following sections for practical training: 1.
- EPIDEMIC COUPLE
C. George Ray (C. George Ray) Definition. Mumps (mumps) is an acute highly contagious disease of viral etiology, characterized by an increase in the parotid salivary glands, and sometimes involvement in the process of the sex glands. meninges, pancreas, and other organs. Etiology. The causative agent of mumps belongs to the family
Mumps (mumps) - refers to acute contagious viral diseases, characterized by fever, general intoxication, an increase and soreness of the salivary glands, mainly the parotid. Etiology. The virus causative agent of mumps infection is unstable, is inactivated by heating (at a temperature of 70 ° C for 10 min), ultraviolet radiation, exposure to formalin solutions
- Epidemic lethargic encephalitis Economo
Economo's epidemic lethargic encephalitis (synonym: epidemic encephalitis type A, "sleeping" disease) was first recorded in 1915 by the troops near Verdun and described in 1917 by the Austrian neuropathologist K. Economo. The disease in those years proceeded in the form of epidemics that swept many countries of the world. In subsequent years, the disease manifested itself sporadically. Current disease in a typical
Mumps (mumps) is a childhood viral infection characterized by acute inflammation in the salivary glands. The causative agent of mumps belongs to the RNA-containing viruses, the genus Paramyxovirus. Infection occurs by airborne droplets. The susceptibility to this disease is about 50-60% (that is, 50-60% of those who were in contact and did not get sick or not vaccinated get sick). Piggy
- EPIDEMIC RETURN TYPE
Peter L. Ferine Definition. Epidemic relapsing fever is an acute infection characterized by repeated cycles of a rise in body temperature, which are separated from each other by asymptomatic intervals of apparent recovery. It is caused by spirochetes of the genus Borrelia and is represented by two epidemiological varieties - a disease transmitted by lice and a disease transmitted
- Piglet Epidemic Diarrhea
Epidemic diarrhea of piglets (womiting and wasting disease in piglets) is an acute infectious disease, mainly piglets older than 4-5 weeks of age, manifested by watery diarrhea. Etiology. The causative agent of the disease is an RNA-containing virus whose morphology is typical of the Coronaviridae family. Epizootological data. The source of the causative agent of the disease are sick animals,
- Epidemic encephalitis
(Economo's disease, sleeping sickness, lethargic encephalitis, primary non-purulent inflammation of the brain). The causative agent of this disease is a filtered virus, which has not yet been isolated. Epidemic encephalitis was first described by Economo in 1917 during an epidemic in Austria, in the USSR — A. I. Geymanovich (Kharkov) and Y. M. Raimistom (Odessa) during an outbreak in 1 & 19
Mumps (mumps) is an acute infectious disease with a primary lesion of the salivary glands. The causative agent is the Pneumophilis parotidis RNA virus from the genus paramyxoviruses. Infection occurs from a patient with manifest or, more often, erased and asymptomatic forms of the disease. The route of infection is airborne. Transmission of the virus through toys and household items infected
- Cerebrospinal epidemic meningitis
Etiology and pathogenesis The disease is caused by meningococcus Frankel-Vekselbaum. This is a gram-negative diplococcus, located most often intracellularly. 4 strains of the pathogen were isolated: A, B, C, D. The disease is transmitted by airborne droplets and contact through objects that were in the patient’s use. The entrance gate is the mucous membrane of the pharynx and nasopharynx. Get sick
- Epidemic typhus (thyphus exanthematicus).
It refers to anthroponous rickettsiosis, is transmitted by lice, is characterized by generalized thrombovasculitis of small vessels and is manifested by severe intoxication, meningoencephalitis, hepatosplenomegaly and polymorphic roseole-petechial skin rash (exanthema). The disease is more often observed between the ages of 20 to 40 years. There is some predominance of men compared with women.
- Section III Ensuring the sanitary-epidemiological well-being of the population
Article 18. Sanitary and epidemic well-being of the population. Sanitary and epidemic well-being of the population of the USSR is ensured by comprehensive sanitary-hygienic and sanitary-epidemiological measures and a system of state sanitary supervision. Conducting sanitary-hygienic and sanitary - anti-epidemic measures aimed at improving the environment