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How HIV is and is not spread, and the proven ways to prevent it: condoms, PrEP, PEP after exposure, testing and HIV treatment.
By Editorial Team · Updated · 2 min read
This article is awaiting review by a qualified medical professional.
Quick answer
HIV can be prevented with condoms, PrEP (which lowers the risk of getting HIV from sex by about 99% when taken as prescribed), PEP started within 72 hours of a possible exposure, and treatment: people with HIV who take their medicine and keep an undetectable viral load cannot pass HIV on to partners through sex.
HIV (human immunodeficiency virus) attacks the immune system. There is no cure, but there are highly effective ways to prevent it, and modern treatment allows people with HIV to live long, healthy lives.
HIV spreads through certain body fluids: blood, semen and pre-seminal fluid, rectal fluids, vaginal fluids and breast milk. It is passed on mainly through:
HIV is not spread through hugging, kissing, sharing food, toilets, swimming pools, or mosquito bites.
Using condoms correctly every time you have vaginal or anal sex greatly lowers your risk of HIV, and also protects against many other STIs. Use water-based or silicone lubricant. See how to use a condom correctly.
Pre-exposure prophylaxis (PrEP) is for people who do not have HIV but are at higher risk, for example those whose partner has HIV, people with multiple partners or inconsistent condom use, and people who inject drugs.
Ask a doctor or sexual health clinic whether PrEP is available and right for you.
Post-exposure prophylaxis (PEP) is a 28-day course of HIV medicine that can stop infection after a possible exposure, for example a condom breaking or sexual assault. It must be started as soon as possible and within 72 hours. The sooner it starts, the better it works. Go straight to an emergency department or sexual health clinic.
A person with HIV who takes treatment as prescribed and keeps an undetectable viral load for at least six months cannot pass HIV to a sexual partner. This is called Undetectable = Untransmittable (U=U). Early treatment protects both the person and their partners.
With HIV treatment during pregnancy and delivery, and medicine for the baby, the chance of passing HIV to the baby can be reduced to under 1%. Pregnant women should be offered an HIV test as part of routine care.
Never share needles, syringes or other equipment. Needle and syringe programmes and sterile supplies reduce the spread of HIV and hepatitis.
Knowing your status is the first step. See HIV symptoms and testing for how and when to test.
Contact a healthcare provider or sexual health clinic if you may have been exposed to HIV, if you want to discuss PrEP, or if you have symptoms. If the exposure was in the last 72 hours, seek care immediately and ask for PEP.
PrEP (pre-exposure prophylaxis) is medicine taken by people who do not have HIV to prevent infection. Taken as prescribed, it reduces the risk of getting HIV from sex by about 99%. It comes as a daily pill and, in some countries, as a long-acting injection.
PEP (post-exposure prophylaxis) is a 28-day course of HIV medicine taken after a possible exposure. It must be started as soon as possible and within 72 hours. Go to an emergency department or sexual health clinic straight away.
No. HIV is not spread by hugging, kissing, sharing food or toilets, mosquito bites, or casual contact.
Not through sex if their viral load stays undetectable. This is known as Undetectable = Untransmittable, or U=U.
This article is for educational purposes only and does not replace advice from a doctor or other qualified health professional. See our medical disclaimer.
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