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How HIV is spread

How HIV is spread

  • Through vaginal or anal sex. Anal sex is riskier than vaginal sex.
  • By sharing needles or syringes, such as when using drugs
  • From a mother to her baby during pregnancy, childbirth, or breastfeeding
  • Through oral sex, but getting HIV from oral sex is very rare. You can get HIV from giving oral sex if infected sexual fluids get into your mouth and you have bleeding gums or mouth sores, or from receiving oral sex if your partner has bleeding gums or a mouth sore.

What types of fluids carry HIV?

You can get infected with HIV if one of the following fluids from an infected person enters your body:

  • Blood, including menstrual blood
  • Semen (cum), including pre-semen (pre-cum)
  • Vaginal fluids
  • Anal mucus (fluids from the anus)
  • Breastmilk

Can I get HIV from sharing needles?

Yes. Sharing needles or syringes and other injection drug equipment is very risky. Sharing needles is the second most common way that HIV is spread to women in the United States (sex is the most common way). Any woman who shares needles with someone is at risk for HIV infection, because the needles may have someone else's blood in them.

Learn more about HIV risk and sharing needles.

Can I get HIV from a piercing or tattoo?

Getting HIV from a piercing or tattoo is rare. But it is possible to get HIV from tattoo and piercing tools that are not sterilized correctly between clients. Tools that cut the skin should be used once, then thrown away or sterilized between uses.

Before you get a tattoo or have your body pierced, ask the right questions. Find out what steps the staff takes to prevent HIV and other infections, like hepatitis B and hepatitis C. A new, sterilized needle should be used for each person.

Learn more about HIV risk and tattoos and body piercing.

Can I pass HIV to my partner?

Many HIV-positive women with HIV-negative partners (also known as serodiscordant or mixed-status couples) worry about passing HIV. Research shows that it is easier for an HIV-positive man to spread HIV to an uninfected woman than for an HIV-positive woman to spread HIV to an uninfected partner. But it is possible for women to spread HIV to their uninfected partners through vaginal, oral, or anal sex. While very rare, it is possible for HIV-positive women to spread HIV to their female sex partner. This is because HIV is in blood (including menstrual blood), vaginal fluids, and cells in the vaginal and anal walls.

If you are HIV-positive, you can pass the virus at any time, even if you are getting treatment. But getting treated with antiretroviral medicine can lower the risk of passing HIV to your partner by 96%.1

How can I prevent passing HIV to my partner?

If you take HIV medicine and your viral load is not detectable in your blood, your chances of passing HIV to your sexual partner is lower. You should always use a latex condom or dental dam with sex. Your HIV-negative partner also can take medicine (called pre-exposure prophylaxis or PrEP) to keep from getting HIV.

Learn more about how to prevent passing HIV to your partner.

How can I prevent passing HIV to my unborn baby?

Today, new medicines mean you can lower your chance of passing HIV to your unborn baby during pregnancy, labor, and childbirth to less than 1%.2 Taking medicine to treat HIV (antiretrovirals, or ARVs) is recommended for everyone who is HIV-positive to lower their viral load and help protect their immune system. Having a viral load that cannot be detected can keep you healthy and also prevent you from passing the virus to your unborn baby. Because HIV can spread in breastmilk, in the United States, you should not breastfeed if you have HIV, even if your viral load cannot be detected.

Learn more about how to prevent passing HIV to your baby.


  1. National Institute of Allergy and Infectious Diseases. (2011). Treating HIV-infected people with antiretrovirals significantly reduces transmission to partners.
  2. Centers for Disease Control and Prevention. (2016). HIV Among Pregnant Women, Infants, and Children.