What are the three major factors that determine the outcome of infectious diseases Briefly describe

Pathogen. Host immunity, environmental conditions.

Relationship: 1. If the human body has strong immunity against infection or pathogenic microorganisms.

If one side appears to be weak, then the body can wipe out all the invading pathogens, thus ensuring that the body is healthy and does not infect;

2. The body has strong immunity against infection, or the invasion of pathogenic bacteria is not strong, and the number is not large, so the damage to the human body after infection is relatively light, and there are no or only inconspicuous clinical symptoms, which is recessive infection;

3. If both the pathogen and the host have advantages, and the pathogen is limited to a certain part and cannot multiply in large quantities, and the two are in a state of holding each other for a long time, it is called the carrier state;

4. The body's anti-infection immunity is weak, or the invasive pathogenic bacteria are strong and numerous, so that the body's tissue cells are damaged to varying degrees, physiological functions are changed, and a series of clinical symptoms appear: local infection, systemic infection.

Hello landlord. 1 Source of infection, route of transmission, susceptible population.

2 The source of infection is the starting point of transmission, and without the source of infection, there would be no infectious disease.

3 The route of transmission is pathogens.

The vector of transmission, without which the pathogen will not be transmitted among the source of infection and healthy people, such as through blood, digestive tract, respiratory tract, etc.

4 Susceptible people are people who are susceptible to a pathogen and generally have low resistance, such as the elderly or people who do not produce antibodies (such as hepatitis B.

If you still have any questions, please notify me after supplementing them.

1 Source of infection, route of transmission, susceptible population.

2 The source of infection is the starting point of transmission, without the source of infection, there will be no infectious disease 3 The transmission route is the vector of pathogen transmission, without which the pathogen will not spread among the source of infection and healthy people, such as through blood, digestive tract, respiratory tract, etc.

4 Susceptible people are people who are susceptible to a certain pathogen and generally have low resistance, such as the elderly or people who do not produce corresponding antibodies (such as hepatitis B, etc.).

a.Exotoxin is produced.

b.Endotoxin is produced.

c.Immunity to poor Hu defense.

d.Celebration with feast burning fungus state.

Correct answer: d

Epidemiology is the study of the spread and impact of diseases in a population. In epidemiology, the three basic conditions for the epidemic process of infectious diseases are: susceptible populations, transmission routes, and pathogens.

1.Susceptible population

Susceptible people are people who do not have immunity and are susceptible to pathogens. In the process of epidemic of infectious diseases, susceptible populations are an important factor in the spread of diseases. If the number of susceptible people is large, the disease spreads faster.

The number of susceptible people depends on several factors, such as the route of transmission of the pathogen, population density, population mobility, etc.

2.Mode of transmission

The route of transmission of an infectious disease refers to the way a pathogen spreads from one person to another. Common transmission routes include: airborne transmission, droplet transmission, contact transmission, water transmission, food transmission, etc.

Different routes of transmission correspond to different preventive measures. For example, airborne diseases can be prevented by wearing masks, ventilation, etc., while waterborne diseases can be prevented by drinking clean drinking water.

3.Pathogen.

Pathogens refer to microorganisms that cause infectious diseases, such as bacteria, viruses, fungi, etc. The viability and transmissibility of pathogens are important factors in determining the speed and extent of disease transmission. For example, some pathogens can survive in the environment for long periods of time, allowing the disease to spread more widely.

Classification of Infectious Diseases:

1. Class A infectious diseases: such infectious diseases mainly include cholera, plague, etc., which need to be compulsorily managed, strictly controlled and isolated for close contact and suspected infection objects, carriers, and epidemic areas, and appropriate methods are used.

2. Class B infectious diseases: This type of infectious diseases mainly infects people with highly pathogenic avian influenza, AIDS, infectious atypical pneumonia, viral hepatitis, measles, Japanese encephalitis, rabies, syphilis, brucellosis, new coronavirus infection, schistosomiasis, etc. Strict control isolation is required and done in the right way**.

3. Class C infectious diseases: mainly including mumps, epidemic, acute hemorrhagic conjunctivitis, leprosy, rubella, filariasis, hand, foot and mouth disease, etc. If it is an infectious disease of this type, surveillance management is required.

The two important factors influencing the epidemic process of infectious diseases are natural factors and social factors.

1. Natural factors.

Each foci occurs from the foci before it, and it itself can trigger new foci, and the continuous occurrence of a series of foci is called the epidemic process. Therefore, the foci are the basic units that constitute the epidemic process of infectious diseases. The epidemic process is both related to and distinct from the contagious process.

The infectious process refers to the process in which pathogens invade the body, interact with the body, and fight each other. The contagion process is only a circulation in the individual organism, while the epidemic process is a group phenomenon.

2. Social factors.

The characteristics of the population distribution of infectious disease epidemics are mainly determined by the level of immunity of the population and the opportunity to be exposed to pathogens. For example, it may be due to the increase in the number of births (susceptible children), or the migration and death of people with immunity, or the migration of people with low immunity level, or the relative quiescence period after the epidemic of an infectious disease, etc., can become the influencing factors of the population distribution characteristics of the epidemic of a certain infectious disease in the local area.

Infectious Disease Prevention Measures:

Controlling the source of infection is the most effective way to prevent infectious diseases. For infectious diseases of human infectious sources, it is necessary to properly arrange patients or disease carriers in designated isolation locations in a timely manner, temporarily isolate them from the crowd, actively carry out **, nursing, and carry out necessary disinfection treatment of infectious secretions and utensils to prevent the spread of pathogens.

Cutting off the route of transmission is the most direct way to prevent infectious diseases transmitted through digestive tract infections, blood and body fluids, insect-borne infections and parasitic diseases. The main ways to do this are to block the vectors, disinfect them or cull them. For example, food or drinking water contaminated with pathogens should be discarded or disinfected.

To protect the susceptible population, when the epidemic of infectious diseases occurs, attention should be paid to protecting the susceptible people, not allowing the susceptible people to come into contact with the source of infection, and to carry out vaccinations to improve the ability to resist and slow down the resistance to infectious diseases. Therefore, the protection of susceptible populations is also an important part of infectious disease prevention, and it is often a relatively easy prevention method to achieve.

Answer] :d process of pathogens interacting with the human body and fighting each other is called infectious disease. The process of contagion must have three factors: the pathogen, the human body, and the environment in which they live. Fighting test site: the epidemic process of infectious diseases.

Pathogen. In order for an infectious disease to occur and spread among a certain population, there must be three basic links: the source of infection, the transmission route and the susceptible population.

1. Source of infection.

People and animals that have pathogens that grow and multiply in their bodies and can excrete pathogens, i.e., people and animals that have infectious diseases or carry pathogens. Patients with infectious diseases are an important source of infection, and there are a large number of pathogens in their bodies. At different stages of the course of the disease, the role of the infectious agent of the patient is different, which is mainly related to the type of disease, the amount of pathogens excreted, and the degree and frequency of contact between the patient and the surrounding population.

2. Mode of transmission.

Refers to the route that a pathogen travels through the environment after it has been excreted from the infectious agent and before it is transmitted to another susceptible person. An infectious disease can be transmitted in a single or multiple ways. The transmission route can be divided into two categories: horizontal transmission and vertical transmission.

3. Population susceptibility.

Refers to the degree of susceptibility of a population to an infectious disease. A large number of people in the population who lack specific immunity to an infectious disease are highly susceptible to the disease, and vice versa, they are said to be less susceptible. The high susceptibility of the population to a disease is the basis for the epidemic of the disease in the population; If the susceptibility is low, the epidemic of the corresponding infectious disease can be suppressed.

Answer]: The three links that constitute the epidemic of infectious diseases are the source of infection, the route of transmission and the susceptible population. Infectious agents refer to people or animals whose pathogens grow and reproduce in their bodies and can excrete pathogens, including infectious disease patients, pathogen carriers, or infected animals.

The route of transmission refers to the entire process that pathogens undergo in the external environment after they are excreted from the source of infection and before they invade a new susceptible host. Susceptibility refers to the degree to which a population as a group is susceptible to infectious diseases.