How does HIV infection develop?
The HIV virus is transmitted through direct contact with blood, semen, vaginal secretions and breast milk. Because the body has not yet formed antibodies (antibodies) to the virus immediately after infection, the amount of virus in the blood is extremely high. New infected people therefore run a high risk of infection.
Usually it is transmitted during unprotected sexual intercourse with an infected partner. 70% of new infections affect homosexual men, 20% of infections occur in heterosexual contacts. In case of unprotected sexual intercourse with an equally infected partner, HIV-infected persons can also be infected by another, possibly resistant, subtype of the HIV virus. A small risk of contamination can also not be ruled out during oral sex contact.
9% of all infected people are drug addicts who share their syringes or needles with others.
15-30% of HIV-infected mothers transfer the disease to their child during pregnancy or childbirth. Treatment with retroviral drugs and birth by caesarean section can reduce the transmission risk to 2%. Since transmission of HIV can also take place via breast milk, mothers with HIV infection should not breast-feed their child.
Infected blood or blood products may contain HIV viruses in such high concentrations that infection is possible. Since 1985, hospitals and blood banks in European countries have been testing blood and blood products, as well as blood donors that repeat HIV antibodies. That is why today the risk of getting infected in this way is negligible. In isolated cases, the HIV virus can be transmitted during tattoos with unclean utensils. According to current knowledge, the risk of infection due to saliva, sweat or tears is extremely low. However, if these fluids come into contact with open wounds, transfer cannot be completely ruled out. While some pathogens spread through the exhaled air, the HIV virus cannot skip coughing or sneezing in other people.
Contrary to what is often thought, the HIV virus is therefore not transmitted by:
- skin contact (hugs or kisses on the cheeks or mouth)
- swimming in swimming pools
- eat together and share knife and fork
- the amount of viruses in sweat, tears and saliva is too small to cause an infection.
- Insect bites