HIV lives in the following areas of the body:
- Semen and vaginal fluid
- Breast milk
To transmit HIV from one person to another the virus needs a route into a persons blood. It needs to be present in a bodily fluid in sufficient quantity to be transmitted.
An easy way to transmit HIV is through a blood transfusion, where HIV infected blood is put straight into someone else’s body. In most countries across the world, blood is treated before being used in transfusion as there are lots of things that can be passed on in this way, not only HIV.
If an HIV positive person is having sex (vaginal or anal) with someone without a condom, the HIV in the semen or vaginal fluid can enter the other person’s body, and enter their blood stream.
If a person with HIV injects him/her self with a needle, then another person injects him/her self with the same needle immediately after, HIV can be passed on. People who are intravenous drug users, and share needles (without sterilising them after each persons use) have a very high risk of either getting infected by, or passing on HIV.
HIV can be passed onto a baby at three stages in their development if the mother is HIV positive:
Whilst they are growing in the womb
There are now steps that an HIV positive woman can take to help stop her baby being born with HIV. These work so well that in the UK now there is less than a 1 in 100 chance an HIV positive woman will give HIV to her baby.
The interventions to prevent mother to child transmission of HIV are:
- Knowing the mother has HIV.
- The mother takes HIV medication during her pregnancy so her viral load (the amount of HIV detected in her blood) becomes ‘undetectable’. This greatly reduces the risk of HIV transmission.
- She either has a controlled vaginal delivery, or an elected caesarean section to reduce the potential for trauma at the time of birth. Trauma during birth can increase the risk of HIV transmission taking place as a lot of bodily fluid exchanges can occur.
- The baby is given HIV medication for 4-6 weeks after birth.
- The baby is not breast fed, and is only fed formula milk.
HIV cannot be transmitted through:
- Unbroken healthy skin- HIV cannot pass through unbroken skin and enter the blood stream.
- Airborne transmission- eg sneezing, coughing, HIV cannot be airborne
- Mosquitos- although Mosquitos suck blood they do not regurgitate blood into the next person they bite.
- Sharing cutlery, plates, cups- HIV cannot be transmitted in saliva.
- Social or household contact with people with HIV as HIV is not transmitted by touch or through the air.
- An unbroken barrier such as a latex condom.