1, classification of infectious diseases
The Law on the Prevention and Control of Infectious Diseases classifies 37 kinds of acute and chronic infectious diseases with high incidence, large epidemic area and serious harm as infectious diseases according to the harm degree of infectious diseases and the supervision, monitoring and management measures to be taken, referring to the international unified classification standards and combining with the actual situation in China, and classifies them into three categories: A, B and C according to their mode of transmission, speed of transmission and degree of harm to human body, and implements classified management.
(1) Class A infectious diseases
Class A infectious diseases are also called compulsory management infectious diseases, including plague and cholera. The time limit for reporting the epidemic situation after the occurrence of such infectious diseases, the isolation of patients and pathogen carriers, the treatment methods, and the treatment of epidemic spots and epidemic areas have all been implemented.
(2) Class B infectious diseases
Class B infectious diseases are also called strictly managed infectious diseases. Including SARS, influenza A H 1N 1, AIDS, viral hepatitis, polio, human infection with highly pathogenic avian influenza, measles, epidemic hemorrhagic fever, rabies, Japanese encephalitis, dengue fever, anthrax, bacterial and amebic dysentery, tuberculosis, typhoid and paratyphoid fever, epidemic cerebrospinal meningitis, whooping cough, diphtheria and neonatal tetanus. Such infectious diseases should be prevented and controlled in strict accordance with relevant regulations and prevention and control programs. Among them, infectious atypical pneumonia, pulmonary anthrax among anthrax, human infection with highly pathogenic avian influenza and influenza A (H 1N 1) are classified as Class B, but the prevention and control measures of Class A infectious diseases can be taken directly.
(3) Twenty-six Class B infectious diseases
Broken linen with a hundred hooks; (Tetanus, measles, brucellosis, whooping cough, leptospira)
Birds gather to suck the brain and liver. (SARS, avian influenza, encephalomyelitis, tuberculosis, schistosomiasis, Japanese encephalitis, hepatitis B)
Grey dog fever, red plum cold, (polio, rabies, epidemic hemorrhagic fever, scarlet fever, syphilis, typhoid fever, paratyphoid fever)
White rice on the altar of AIDS. (Diphtheria, amebic dysentery, bacillary dysentery, dengue fever, gonorrhea, AIDS, anthrax)
(4) Class C infectious diseases
Class C infectious diseases, also known as monitoring and managing infectious diseases, include Japanese encephalitis, mumps, rubella, acute hemorrhagic conjunctivitis, leprosy, epidemic and endemic typhus, leishmaniasis, echinococcosis, filariasis, infectious diarrhea other than cholera, bacterial and amebic dysentery, typhoid fever and paratyphoid fever. Such infectious diseases shall be managed in accordance with the monitoring and management measures stipulated by the health administrative department of the State Council.
2, according to the different routes of transmission
There are many kinds of infectious diseases in human beings, which can be divided into four categories according to different transmission routes: respiratory infectious diseases, digestive infectious diseases, blood infectious diseases and body surface infectious diseases.
(1) respiratory infectious diseases
Respiratory infectious diseases refer to infectious diseases caused by pathogens invading respiratory mucosa, including epidemic encephalitis, diphtheria, whooping cough, scarlet fever, tuberculosis, mumps, measles and epidemic cerebrospinal meningitis. These diseases mostly occur in winter and spring, and patients and carriers are the main sources of infection. The initial parasitic sites of pathogens are respiratory mucosa and lungs, which are mainly spread by droplets and air (below). Don't spit everywhere, keep the air circulation in houses and public places, and wear masks to prevent the occurrence of respiratory infectious diseases.
(2) Infectious diseases of digestive tract
Infectious diseases of digestive tract refer to infectious diseases caused by pathogens invading digestive tract mucosa, including bacillary dysentery, viral hepatitis, typhoid fever, polio, ascariasis, ascariasis and so on. These diseases mostly occur in summer and autumn, and patients and infected animals are the main sources of infection. The initial parasitic site of pathogens is the digestive tract and its affiliated organs, which are mainly transmitted through drinking water and food (below). Therefore, don't drink raw water, don't eat raw vegetables and fruits, vigorously eliminate flies, and wash your hands before and after meals. Can prevent the occurrence of infectious diseases in the digestive tract.
(3) Blood infectious diseases
Blood infectious diseases refer to infectious diseases caused by arthropods (such as mosquitoes, lice, fleas, ticks, etc.). ), so it is also called insect-borne infectious diseases, including malaria, Japanese encephalitis, kala-azar, filariasis, hemorrhagic fever and so on. Patients and infected animals are the main sources of infection. The original parasitic parts of pathogens are blood and lymph, which are mainly transmitted by blood-sucking arthropods (below). Carrying out patriotic health campaign and eliminating blood-sucking arthropods such as mosquitoes and lice can prevent the occurrence of blood infectious diseases.
(4) Infectious diseases on the body surface
Body surface infectious diseases refer to infectious diseases caused by direct or indirect contact with sick people and animals, or contact with soil and water containing pathogens. Pathogens enter the human body through the skin, so they are also called contact infectious diseases, including rabies, anthrax, tetanus, schistosomiasis, trachoma, scabies and tinea. The initial parasitic sites of pathogens are skin and body surface mucosa, which are mainly transmitted through contact (below). Isolation of patients, good personal hygiene and no contact with people or animals with pathogens can prevent the occurrence of surface infectious diseases.
3. Characteristics of infectious diseases
Infectious diseases are characterized by pathogenicity, infectivity and epidemic, and often have immunity after infection. Some infectious diseases are seasonal or endemic. The classification of infectious diseases has not been unified. Some people classify by pathogen, others by transmission route. The prevention of infectious diseases should take comprehensive measures leading by cutting off the main transmission links. The spread and prevalence of infectious diseases must have three links, namely, the source of infection (people or animals that can expel pathogens), the way of transmission (the way pathogens infect others) and the susceptible population (people who are not immune to this infectious disease). If we can completely cut off one of the links, we can prevent the occurrence and prevalence of this infectious disease. The weak links of various infectious diseases are different. We should make full use of it in prevention. In addition to the leading link, measures should be taken for other links. Only in this way can we better prevent various infectious diseases.
4, the route of transmission of infectious diseases
Because biological pathogens have different survival time in vitro and different positions and activities in human body, all these will affect the process of how infection spreads. In order to survive and reproduce, these pathogenic microorganisms must be infectious. Each infectious pathogen usually has a specific mode of transmission. For example, through the respiratory tract, some bacteria or viruses can cause changes in the mucosal layer on the surface of the host's respiratory tract, stimulate nerve reflex and cause symptoms such as coughing or sneezing, thus returning to the air and waiting for the next host to ingest. However, some microorganisms can cause digestive system abnormalities, such as diarrhea or vomiting, and spread everywhere with the discharge. In these ways, the replicated pathogens can spread widely with the range of patients' activities.
(1) airborne infection
Some pathogens can spread freely in the air, usually with a diameter of 5 microns, and can float in the air for a long time and move far, mainly respiratory infection, sometimes confused with droplet infection.
(2) droplet infection
Droplet infection is the main route of transmission of many infectious pathogens. When patients cough, sneeze and talk, they spit out warm and moist droplets, and pathogens attach to them, floating in the wind for a short time and a short distance with air disturbance, and the next host attaches when breathing, opening his mouth or accidentally touching the eye surface, resulting in new host infection. For example: bacterial meningitis, chicken pox, common cold, epidemic encephalitis, mumps, tuberculosis, measles, rubella, whooping cough, etc. Because the quality and quantity of droplets are very small, it is difficult to carry heavy pathogens, so parasitic infection will hardly spread to other individuals through this way.
(3) fecal infection
This is very common in developing countries where health systems are not perfect and education is not advocated. Untreated wastewater or pollutants contaminated by pathogens are directly discharged into the environment, which may pollute drinking water, food or utensils that come into contact with oral and nasal mucosa, and may not be thoroughly cleaned after going to the toilet. Intakers may be infected through the eating process. The main pathogens may be viruses, bacteria and parasites, such as cholera, hepatitis A, polio, rotavirus and toxoplasmosis. Sometimes, some organisms may be infected by contact with patients' excrement, because their body surface tissue structure is not enough to protect individuals. Under normal circumstances, this special case will not happen in human groups.
(4) Contact infection
The way of direct contact is called contact infection. In addition to touching and kissing patients directly, such diseases can also be spread by sharing personal equipment such as toothbrushes, towels, razors, tableware and clothes, or leaving pathogens in the environment after contact with patients. Therefore, such infectious diseases often occur in schools, military and other places where things may be inadvertently shared. For example, athlete's foot infected by fungi, impetigo infected by bacteria, and wart caused by epidermal virus. Syphilis is a special case, which is usually caused by healthy individuals touching the chancre of infected people.
Sexually transmitted diseases include any disease that can be transmitted through sexual behavior, so it is a contact infection. However, due to the serious AIDS epidemic worldwide, it is sometimes discussed separately in medicine. Usually, the main source of infection is bacteria or viruses, which are transmitted to sexual partners through direct contact with genital mucosa, semen, female private secretions and even pathogens carried by rectum, leading to infection. If there are wounds in these parts, pathogens may bring blood infection to all parts of the body.
(5) Vertical transmission
Vertical infection refers to the disease that the fetus gets from its mother. In Latin, "inutero" means "in the womb". Usually, the pathogens that infect the fetus through this way of infection are mainly viruses and small parasites with high activity, which can be transported through blood or have the ability to pass through tissues or cells, so they can be transmitted from mother to child through placenta, such as AIDS and hepatitis B. Although there are few bacteria in vertical infection, syphilis can be infected during delivery because the mucosa or eyes of the fetus come into contact with the infected mucosa of the mother's private parts. In a few cases, it infects newborns through milk secretion during breastfeeding. The latter two routes also belong to the category of vertical infection.
(6) Blood infection
Blood infection is the process of transferring diseases to another individual mainly through blood and wound infection. It is very common in the medical use of injection equipment and blood transfusion technology. Therefore, many medical institutions require that the implementation of relevant medical procedures must be confirmed by many people to avoid hurting patients. During blood donation and transfusion, blood donors and recipients should be further examined to reduce the risk of such infection. However, due to the use of drugs, sharing needles will cause infections that are difficult to prevent, especially for the prevention of AIDS.
Respiratory infectious diseases: epidemic diseases, tuberculosis, mumps, measles, whooping cough, etc. (airborne).
Infectious diseases of digestive tract: ascariasis, bacillary dysentery, hepatitis A, etc. (transmitted by water and diet).
Blood infectious diseases: hepatitis B, malaria, Japanese encephalitis, filariasis, etc. (spread through biological media, etc. ).
Infectious diseases on body surface: schistosomiasis, trachoma, rabies, tetanus, gonorrhea, etc. (contact transmission).
5. Preventive measures against infectious diseases
The most effective way to control infectious diseases lies in prevention and control, because the lack of any of the three basic conditions of infectious diseases: the source of infection, the route of transmission and the susceptible population can not cause the epidemic of infectious diseases, so the prevention of infectious diseases mainly focuses on these three aspects:
(1) Control the source of infection
This is the most effective way to prevent infectious diseases. For human-borne infectious diseases, patients or pathogen carriers should be properly placed in designated isolation locations in time, temporarily isolate people, actively carry out treatment and nursing, and carry out necessary disinfection treatment on infectious secretions, excreta and utensils to prevent the spread of pathogens. However, if the source of infection is unknown, especially animals, it is not easy to get exact results because of the need for epidemiological causal inference and sufficient evidence of laboratory test results, especially in the case of sudden acute infectious diseases, it is even more difficult to locate the source of infection in a short time. However, once the source of infection is determined, effective measures should be taken to control the source of infection in time to ensure that the source of infection will not continue to spread pathogens to susceptible people.
(2) cut off the route of transmission
For infectious diseases, insect-borne diseases and parasitic diseases transmitted through digestive tract, blood and body fluids, cutting off the transmission route is the most direct prevention method. The main way is to block, disinfect or cull the media. For example, food or drinking water contaminated by pathogens should be discarded or disinfected, rooms or utensils contaminated by pathogens should be fully disinfected, disposable medical supplies should be disinfected or burned in time after use, and measures should be taken to prevent mosquitoes and insects in the season when insect-borne infectious diseases spread. At the same time, it is also extremely necessary to intervene in health education for high-risk groups, such as advocating intravenous drug users to disinfect needles and educating people who will have high-risk sex on condom use. At present, the methods to prevent influenza A (H7N9) virus are still paying attention to basic hygiene, washing hands frequently, wearing masks and eating cooked meat-although it is the same old tune, it is still the most effective way to cut off the transmission route.
(3) Protect the susceptible population
Protecting susceptible people is also an important part of infectious disease prevention, which is often a relatively easy prevention method. For infectious diseases with preventive vaccines, vaccination is the safest way for susceptible people, such as planned immunization for infants after birth, vaccination for infectious diseases doctors, nurses, researchers engaged in infectious diseases research and poultry farmers. In history, people successfully conquered smallpox with highly effective vaccines, which proved the important role of protecting susceptible people in the prevention and treatment of infectious diseases.
6. Prevent the risk of being popular and cute.
Influenza virus can spread in the air through saliva drops, nose and sputum. Influenza is highly contagious, with rapid onset and severe symptoms, and is prevalent in winter and spring.
Compared with the common cold, patients with influenza usually have symptoms above 38℃, with obvious pain and headache, but less cough and runny nose. Influenza is extremely harmful to the elderly, children, pregnant women and the infirm, and can lead to death in severe cases.
Precautions:
1, pay attention to keep indoor ventilation at ordinary times, even in winter, open the window for ventilation more than three times a day, at least 10- 15 minutes each time. Household air conditioners should be cleaned before use every year to ensure clean ventilation.
2. Don't spit everywhere. Cover your nose and mouth with a tissue when sneezing or coughing.
3, reasonable arrangements for work and rest, regular life, to ensure adequate sleep, to avoid overwork leading to decreased resistance, thereby increasing the chance of illness.
4. When the flu is prevalent, you should try to go to crowded public places such as shopping malls and theaters as little as possible. You must wear a mask.