Several modes of transmission of AIDS introduce how long AIDS can live.

Aids patients and HIV carriers. HIV exists in the body fluids and organs of infected people. The blood, semen, vaginal secretions, milk and wound exudates of infected people contain a large number of HIV, which is highly contagious. This virus rarely contains blood and inflammatory exudates.

What are the transmission routes of AIDS?

1. Sexual contact transmission

Sexually transmitted HIV exists in the semen and vaginal secretions of infected people and is transmitted between men and women through sexual intercourse (including normal sexual intercourse, anal sex and oral sex). Nine out of every 65,438+00 adults infected with HIV in the world are transmitted through sexual intercourse. The more sexual partners, the greater the risk of HIV infection. STD patients are easily infected with HIV when they have sex with HIV-infected people.

Sexual transmission is the main route of HIV infection. Whether homosexual or heterosexual, HIV transmission may occur. Around the world, HIV is mainly transmitted through heterosexual contact. Among adults. HIV is shown in the following table:

Propagation ratio

Heterosexual transmission 7 1%

Homosexual transmission 15%

7% intravenous drug users

Bloody spread 5%

2% is due to other unknown reasons.

In North America and Europe, sexual contact between gay men-anal sex is the main mode of transmission of this disease. Gay men and bisexuals constitute the main groups of HIV infection. AIDS patients discovered in the early 1980s in the United States are mainly gay men. Anal sex between gay men can easily lead to anal and rectal mucosal damage, which opens a channel for HIV to enter the blood, making it contain a lot of semen and male secretions before ejaculation of HIV, and enter the blood circulation through the damaged mucosa. In addition, gay men often change sexual partners, and some homosexuals have dozens or hundreds of sexual partners, which increases the probability of being infected with HIV. In Africa, Latin America and Southeast Asia, the vast majority of AIDS is infected through heterosexual contact and vaginal intercourse. The incidence of AIDS in men and women is 1: 1. The heterosexual transmission of HIV can be divided into two ways: male-female transmission or female-male transmission. Compared with these two ways, the risk of transmission between men and women is higher than that of women. Male transmission. Semen and cervical secretions can carry HIV. From the anatomical point of view, secretions can remain in women, not men, so the exchange of semen and cervical secretions in men is more effective for women's transmission. In some African countries, the custom that a wife inherits from her husband's brother after his death aims to prevent the loss of family property. However, this legacy has inherited a deadly dowry in Africa where AIDS is prevalent, and that is HIV. HIV-positive wives can transmit the virus to their husbands' brothers, so men, women and men are important transmission routes in Africa. Prostitution and whoring play an important role in the spread of AIDS. Clients infected with HIV transmit the virus to prostitutes, and prostitutes transmit the virus to other clients. If there are sexually transmitted diseases, the probability of spreading HIV will greatly increase. Genital erosion and ulcer open the channel for the virus to enter the blood circulation, and the party with genital ulcer is more likely to be infected with HIV. In Southeast Asia, since 1990, the prevalence of prostitution has led to the rapid spread of HIV infection. The HIV infection rate is increasing at an alarming rate.

Bisexuality is not only dangerous to male sexual partners, but also dangerous to female sexual partners. Many bisexual people are married and may often go whoring. These bisexuals who marry or have frequent sexual relations with the opposite sex may also introduce homosexual transmission to heterosexuals. Therefore, homosexual and heterosexual behaviors of bisexual men play an important role in the spread of HIV.

The main sexual behaviors related to the spread of HIV are anal sex and vaginal sex. Oral sex is rarely reported and considered as a low-risk sexual behavior. However, if there is oral mucosal erosion or ulcer, it will obviously increase the risk of oral sex to spread HIV.

2. Blood transmission

It is mainly transmitted by importing blood and blood products contaminated by HIV or using syringes and needles contaminated by HIV but not strictly disinfected. It can also be spread by tattooing contaminated needles without strict disinfection, piercing ears, acupuncture, using razors and toothbrushes with patients and infected people.

* * * Use injection instruments contaminated by HIV, import injection instruments contaminated by HIV, transplant blood or blood components contaminated by HIV, and spread tissues and organs contaminated by HIV through blood. In the United States and Western Europe, intravenous drug use has become HIV in some provinces and cities in southern China, and intravenous drug use is the main way to spread AIDS. The spread of HIV is due to the use of blood-contaminated needles, syringes and injectable portable devices. At the same time, drug users are mostly sexually active people, and many of them have HIV infection caused by sexual behavior. They engage in sex trade or prostitution in exchange for drugs or money. It was found that, generally speaking, in hospitals, needles and needles contaminated by HIV only pierce the skin once, and the probability of being infected with HIV is 0.3%. Intravenous drug users often draw blood repeatedly to wash the drugs in the tube, and the blood contaminated by HIV remains in the needle tube. Under normal circumstances, HIV can survive in blood at room temperature for 15 days, and other drug users will also be infected when using contaminated syringes. With the increase in the number of syringes used, the risk of HIV infection is also increasing. On the other hand, the desire for sexual contact tends to increase after taking drugs. If sex is exchanged for drugs, it will further increase the risk of HIV infection.

Blood transfusion or blood components is one of the important transmission routes in the early stage of AIDS epidemic. With the development of modern medicine, blood transfusion or blood products are more and more widely used, and countless patients' lives have been saved through blood transfusion and blood products. But if the transfusion is blood or blood products contaminated by HIV, it is the direct input of HIV blood circulation. Blood components, such as coagulation factor VIII concentrated solution, are extracted from the plasma of many blood donors, so there is a greater chance of polluting HIV. About 6% of blood donors in the United States carry HIV. Therefore, in the early 1980 s, the factor concentrate produced in the United States infected hemophiliacs all over the world. A blood center in France was infected with HIV, resulting in thousands of healthy blood recipients infected with AIDS. These painful lessons must arouse vigilance. At present, developed countries have strengthened the screening of blood donors, and China is also constantly strengthening the management of blood donors and blood products. If the blood donor is infected with HIV, if the blood supply is in the window period, there will be no HIV antibody. None of the blood donors can detect it. Because of HIV testing, HIV antigen equipment is complicated and expensive. In view of this, it is very important to strengthen and improve the screening system for blood donors. Blood transfusion and blood transfusion products must be cautious.

Organ transplantation technology is an important development of modern medicine. Many end-stage heart, lung, liver, kidney and other organ diseases can be regenerated by organ transplantation, but the damaged organs are potentially dangerous. Regular organ donation for HIV antibody testing can significantly reduce the spread of HIV after organ transplantation. The Centers for Disease Control reported that many transplant recipients were infected with HIV in kidneys, liver and bone marrow. These iatrogenic transmissions still exist in developed countries, and the prevalence of AIDS in these countries is gradually decreasing. Although the number of people infected by this mode of transmission is small, it has a great impact because it is related to public health.

3. Mother-to-child transmission. Mother is an AIDS patient or infected person. During pregnancy and childbirth, HIV is transmitted to the fetus or newborn through blood or postpartum breast milk. One third of women infected with HIV may get HIV from their mothers. Most children infected with HIV die before the age of 3.

1982 first reported the vertical transmission of AIDS from mother to child. This transmission may occur in the uterus, childbirth and postpartum lactation, and HIV is transmitted to babies through breast milk.

HIV can be transmitted from the placenta to the fetus. Studies have proved that the fetus can isolate HIV from the fetus who miscarried in the eighth week of pregnancy. The infection rate of the mother to the fetus determines the development stage of HIV infection and the immune function of the mother, such as the number of T4 lymphocytes. After the fetus is infected with HIV in the uterus, it will affect the embryonic development, and it is easy to abort, or the fetus will develop into AIDS at birth. The earlier the fetus is infected with HIV in the uterus, the greater the possibility of abortion or affecting fetal development. The earlier AIDS-related symptoms appear after birth, the shorter the survival time. From 1989 to 1993, Ndola Children's Hospital in Zambia treated 265 newborns infected with HIV/AIDS. 86% of them occurred in the first three weeks after birth, including sepsis, bronchitis, deep jaundice and skin damage. 5% died within 3 months after birth. Newborns who get sick within 1 month after birth generally live less than 6 months. Mother-to-child transmission may also occur during vaginal delivery. If the skin and mucosa of the fetus are damaged during childbirth, the blood of the mother will also be damaged. HIV enters the baby's blood circulation through the baby's wound. It is reported that caesarean section can reduce mother-to-child transmission of HIV.

The mother's milk infected with HIV can isolate the virus, while breast-fed babies can be infected with HIV. It is reported that the mother was infected with HIV through blood transfusion after delivery, and the baby was infected with HIV after breastfeeding for 6 months. However, it is not clear how likely it is to be infected with HIV through breastfeeding. American health authorities advise mothers infected with HIV not to breastfeed. In many African countries, due to backward economic conditions and insufficient breast milk substitutes, stopping breastfeeding will lead to serious malnutrition and HIV infection. Therefore, in many African countries, it endangers the survival of babies more quickly. Mothers infected with HIV still advocate breastfeeding.

Measures to prevent mother-to-child transmission of HIV include persuading women infected with HIV not to give birth and finding out that they are pregnant.

Pregnancy should be terminated. Because the fetus is infected with HIV, most babies who die within three years after birth will also become children suffering from chronic diseases and orphans who have lost their mothers. It faces many moral, moral and emotional problems.

How long can AIDS live?

How long can HIV live? This is related to the environment and blood or body fluids leaving the human body. The specific contents of HIV are as follows:

1.HIV can survive in a liquid environment at room temperature 15 days.

2. If the blood is not dry, leave it at room temperature for 96 hours. Even if HIV is a drop of blood the size of a needle tip, it will still have vitality when it meets fresh lymphocytes. HIV can still enter and replicate, and it is contagious.

3. The contaminated HIV will be infected for at least 3 days.

4. The blood content of HIV is low, and after 2 hours of natural drying, it loses its vitality.

5. The blood content of HIV is high. Even after drying for 2~4 hours, lymphocytes can still enter and replicate once they are put into the culture medium.

It is not difficult to see that isolated blood or body fluids containing HIV can cause infection. HIV is also very fragile. The following is the inactivation of HIV:

1. Heating the liquid to 56 degrees 10 minute can inactivate HIV in the liquid. If it is boiled, it can be inactivated quickly.

2. At 37℃, 70% alcohol, 10% bleaching powder, 2% glutaraldehyde, 4% formalin, 35% isopropanol, 0.5% lysol and 0.3% hydrogen peroxide can inactivate HIV 10 minute.

3. HIV can only live in cells in blood and body fluids, but not in air, water and food. Without these blood and body fluids, HIV will soon die.

In addition, after HIV enters the digestive tract, it will be destroyed by protease in the digestive tract. Contacts in daily life, such as shaking hands, kissing, eating together, sharing a room or office, touching the phone, door handle, toilet utensils, sweat or tears, will not be infected with AIDS.