HIV is found in the body fluids of a person living with HIV. There may be enough HIV to be infectious in semen, genital fluids*, blood and breast milk. However if someone with HIV is on treatment with an undetectable viral load they cannot pass on HIV.
*Definition of genital fluids: Vaginal and cervical secretions, semen (cum), pre-ejaculate (pre-cum) and rectal secretions
To pass on the virus, infectious body fluids need to get into someone else’s bloodstream.
If someone with HIV is taking HIV medication and has an undetectable viral load they cannot pass on HIV.
If someone with HIV is infectious they can pass on HIV through the following body fluids:
This can be prevented by using a condom during sex, or by the HIV negative person taking Pre-exposure prophylaxis (PrEP).
People who inject drugs can avoid HIV being passed on by not sharing drug injecting equipment.
During pregnancy your doctor will advise you how to protect your baby.
During sex body fluids from someone with HIV can get inside a person who is HIV negative.
If the person with HIV has a detectable viral load the virus can enter the HIV negative person’s bloodstream. This can happen during vaginal and anal sex (and sometimes oral sex too, though this is much less common).
It can also happen when an object (eg, a sex toy) that has infectious body fluids on it is put inside an HIV negative person.
It’s also important to remember that if you have sex without a condom other sexually transmitted infections (STIs) can be passed on.
Sex without a condom can also result in an unplanned pregnancy if other contraception is not being used.
Someone with HIV is infectious if they have a detectable viral load.
This is often during the first few months after infection when they have very high levels of the virus in their body fluids and may not yet have been diagnosed.
Early diagnosis means you can start treatment to protect your health and reduce your viral load to undetectable levels.
Protected sex is where you use a male or female condom during sex if one of you has HIV and a detectable viral load.
Condoms should be used with water-based lubricant as oil-based lube weakens them.
HIV treatment is also a form of protection.
HIV isn’t actually as infectious as many other STIs. It isn’t automatically passed on every time a positive person with a detectable viral load and a negative person have unprotected sex, for example.
Other factors that can affect the risk of HIV being passed on:
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This article was last reviewed on
by Anna Peters
Date due for the next review: 23/11/2018
Content Author: Kerri Virani
Current Owner: Kerri Virani
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