What are the three main transmission routes of HIV?

Reply content: Hi, regarding the three main transmission routes of HIV, let me explain them in simple terms:

Three Main Transmission Routes for HIV/AIDS

Key point to remember: The HIV virus is primarily present in an infected person's blood, semen, vaginal fluid, breast milk, and wound exudate. Infection can only occur if a sufficient amount of these body fluids enters your body.

1. Sexual Contact Transmission

This is currently the primary mode of transmission.

What actually happens? During unprotected sex (including vaginal intercourse, anal sex, oral sex), the virus can enter the bloodstream of one partner through tiny, often microscopic, tears in the genitals, rectum, or oral mucosa of the other.
Why is anal sex particularly high-risk? Because the lining (mucosa) of the rectum is thinner and more fragile than the vagina, making it more susceptible to tearing during friction. This makes it easier for the virus to enter the body through this route.
Simply put: Any unprotected sexual activity involving "fluid exchange" carries risk. Correct and consistent use of condoms is the most effective way to prevent sexual transmission.

2. Blood Transmission

This is also straightforward: the virus enters your body directly or indirectly through blood.

Main scenarios include:
- Sharing needles for drug injection: This is extremely high-risk behavior. If multiple people share the same needle or syringe to inject drugs, and one person is infected, residual blood in the equipment can easily transmit the virus to the next person.
- Transfusion of contaminated blood or blood products: Blood used in reputable hospitals today undergoes rigorous screening, making the risk of transmission via transfusion extremely low. However, risks may still exist with non-standardized medical procedures.
- Using improperly sterilized medical, tattooing, or piercing tools: For example, during tattooing, ear piercing, or dental work, if equipment is not strictly sterilized or is reused between clients without proper disinfection, residual blood from an infected person on the tools can serve as a vector for transmission.
Important Note: Mosquito bites do not transmit HIV. The HIV virus cannot survive or replicate inside a mosquito.

3. Mother-to-Child Transmission (Vertical Transmission)

This refers to an HIV-infected mother transmitting the virus to her baby during pregnancy, delivery, or breastfeeding.

When transmission can occur:
- During pregnancy: The virus can cross the placenta and infect the fetus.
- During childbirth: The baby can come into contact with the mother's blood and vaginal fluids while passing through the birth canal.
- Breastfeeding: The virus is present in breast milk and can be transmitted to the infant during breastfeeding.
The good news is: This route can now be very effectively prevented. If an HIV-positive pregnant woman undergoes the standard medication regimen to prevent transmission (often called "prevention of mother-to-child transmission" or PMTCT), including receiving antiretroviral therapy during pregnancy and postpartum and choosing formula feeding, the probability of the baby becoming infected can be reduced to 1%-2% or lower.

Summarizing common daily concerns

Remember, the HIV virus is fragile and quickly becomes inactive once outside the human body. Therefore, the following types of everyday contact absolutely cannot transmit HIV:

Eating or drinking together
Hugging, shaking hands
Sharing office supplies, toilets, bathtubs
Swimming in the same pool
Coughing, sneezing
Insect bites (like mosquito bites)

Hope this explanation helps. Understanding the correct transmission routes allows you to protect yourself effectively while also helping us to eliminate unnecessary panic and discrimination against people living with HIV.