Ways HIV Can Be Transmitted
Most people who get HIV get it through anal or vaginal sex, or sharing needles, syringes, or other drug injection equipment (for example, cookers). But there are powerful tools that can help prevent HIV transmission.
You can get HIV if you have anal sex with someone who has HIV without using protection (like condoms or medicine to treat or prevent HIV).
- Anal sex is the riskiest type of sex for getting or transmitting HIV.
- Being the receptive partner (bottom) is riskier for getting HIV than being the insertive partner (top).
- The bottom’s risk of getting HIV is very high because the rectum’s lining is thin and may allow HIV to enter the body during anal sex.
- The top is also at risk because HIV can enter the body through the opening at the tip of the penis (or urethra), the foreskin if the penis isn’t circumcised, or small cuts, scratches, or open sores anywhere on the penis.
You can get HIV if you have vaginal sex with someone who has HIV without using protection (like condoms or medicine to treat or prevent HIV).
- Vaginal sex is less risky for getting HIV than receptive anal sex.
- Either partner can get HIV during vaginal sex.
- Most women who get HIV get it from vaginal sex. HIV can enter a woman’s body during vaginal sex through the mucous membranes that line the vagina and cervix.
- Men can also get HIV during vaginal sex. This is because vaginal fluid and blood can carry HIV. Men get HIV through the opening at the tip of the penis (or urethra), the foreskin if the penis isn’t circumcised, or small cuts, scratches, or open sores anywhere on the penis.
HIV can be transmitted from a mother to her baby during pregnancy, birth, or breastfeeding. However, it is less common because of advances in HIV prevention and treatment.
- This is called perinatal transmission or mother-to-child transmission.
- Mother-to-child transmission is the most common way that children get HIV.
- Recommendations to test all pregnant women for HIV and start HIV treatment immediately have lowered the number of babies who are born with HIV.
- If a mother with HIV takes HIV medicine daily as prescribed throughout pregnancy and childbirth, and gives HIV medicine to her baby for 4 to 6 weeks after giving birth, the risk of transmitting HIV to the baby can be less than 1%.
You are at high risk for getting HIV if you share needles, syringes, or other drug injection equipment (for example, cookers) with someone who has HIV. Never share needles or other equipment to inject drugs, hormones, steroids, or silicone.
- Used needles, syringes, and other injection equipment may have someone else’s blood on them, and blood can carry HIV.
- People who inject drugs are also at risk for getting HIV (and other sexually transmitted diseases) because they may engage in risky sexual behaviors like having sex without protection (such as condoms or medicine to prevent or treat HIV).
- You’re also at risk for getting hepatitis B and C, and other infections if you share needles, syringes, or other injection equipment.
There is little to no risk of getting HIV from the activities below. For transmission to occur, something very unusual would have to happen.
- Oral sex involves putting the mouth on the penis (fellatio), vagina (cunnilingus), or anus (rimming).
- Factors that may affect this risk include ejaculation in the mouth with oral ulcers, bleeding gums, or genital sores, and the presence of other sexually transmitted diseases (STDs).
- You can get other STDs from oral sex. And if you get feces in your mouth during anilingus, you can get hepatitis A and B, parasites like Giardia, and bacteria like Shigella, Salmonella, Campylobacter, and E. coli.
- The most likely cause is being stuck with a contaminated needle or another sharp object.
- Careful practice of standard precautions protects patients and health care personnel from possible occupational HIV transmission.
- The US blood supply and donated organs and tissues are thoroughly tested, so it is very unlikely that you would get HIV from blood transfusions, blood products, or organ and tissue transplants.
- You cannot get HIV from donating blood. Blood collection procedures are highly regulated and safe.
- The only known cases are among infants. Contamination occurs when blood from a caregiver’s mouth mixes with food that is pre-chewed before feeding to an infant.
- You can’t get HIV from consuming food handled by someone with HIV.
- Each of the very small number of documented cases has involved severe trauma with extensive tissue damage and the presence of blood. Transmission can occur when there is contact between broken skin, wounds, or mucous membranes and blood or body fluids mixed with the blood of a person who has HIV.
- There is no risk of transmission if the skin is not broken.
Deep, Open-Mouth Kissing
- Although very rare, transmission can occur if both partners have sores or bleeding gums and blood from the partner with HIV gets into the bloodstream of the HIV-negative partner.
- HIV is not transmitted through closed-mouth or “social” kissing with someone who has HIV.
- HIV is not transmitted through saliva.
- Case reports of female-to-female transmission of HIV are rare.
- Vaginal fluids and menstrual blood may carry the virus and exposure to these fluids through mucous membranes (in the vagina or mouth) could potentially lead to HIV infection.
Tattoos and Body Piercings
- There are no known cases in the United States of anyone getting HIV this way.
- However, it is possible to get HIV from tattooing or body piercing if the equipment used for these procedures has someone else’s blood in it or if the ink is shared. This is more likely to happen when the person doing the procedure is unlicensed because of the potential for unsanitary practices such as sharing needles or ink.
- If you get a tattoo or a body piercing, be sure that the person doing the procedure is properly licensed and that they use only new or sterilized needles, ink, and other supplies.