- Sex and HIV
- Anal sex and HIV
- Vaginal sex and HIV
- Oral sex and HIV
- Sex toys, fingering, fisting and HIV
- Kissing and HIV
- Other factors
- Pre-exposure prophylaxis (PrEP)
- Antiretroviral treatment
- Dental dams
- Post-exposure prophylaxis (PEP)
- Testing for HIV
- Ways HIV Can Be Transmitted
- Oral Sex
- Medical Care
- Pre-Chewed Food
- Deep, Open-Mouth Kissing
- Tattoos and Body Piercings
- Risk of exposure to HIV/AIDS
- Challenges in calculating a number
- All exposures are not equal
- Anal sex
- Vaginal sex
- Oral sex
Sex and HIV
- HIV can be transmitted through vaginal or anal sex.
- HIV is contained in bodily fluids, such as semen (cum), vaginal fluid, blood and anal mucus, which can pass into the other person’s body during sex.
- You can keep yourself and your partner safe during sex by using a physical barrier, such as a condom; by taking PrEP, an anti-HIV drug, (if you are HIV-negative); and by taking antiretroviral drugs (if you are HIV-positive) to reduce your viral load to an ‘undetectable’ level.
- The risk of getting HIV can vary depending on the type of sex that you have.
- Having sex without a condom also puts you at risk of getting other STIs.
HIV is transmitted through semen (cum and pre-cum), vaginal fluid, blood, and anal mucus. During sex without a condom the bodily fluids from one person can pass into the body of their sexual partner. This can happen through the mucous membranes of the penis, vagina and rectum, or sores in the mouth and throat.
You can only get HIV from someone who is living with HIV and has a detectable viral load.
Anal sex and HIV
Anal sex has the biggest HIV risk because the lining of the anus is more delicate than the lining of the vagina. This means it is more easily damaged, providing an easier route for HIV to enter the body. Receptive anal sex (‘bottoming’) carries more risk than insertive anal sex (‘topping’).
Vaginal sex and HIV
Both male and female partners can get HIV from vaginal sex. The risk of getting and passing on HIV through vaginal sex increases during menstruation.
Oral sex and HIV
The risk of getting HIV from unprotected oral sex is extremely low. It only poses a risk if the person giving oral sex has mouth ulcers, sores or bleeding gums, or the person receiving oral sex has sores on their genitals.
Sex toys, fingering, fisting and HIV
Sex toys, such as dildos, come into direct contact with rectal/vaginal fluids and mucous membranes. This means sharing an uncleaned dildo or other toy can pass on HIV. Using sex toys on your own has no risk.
There is no direct risk of HIV from fingering or fisting (unless you have open cuts or sores on your hands), but be aware of being rough. Damage to anal/vaginal tissues, especially if there is any bleeding, will increase risk of HIV transmission if you then have anal, vaginal or oral sex later.
Kissing and HIV
There is such a small amount of HIV in the saliva of a person living with HIV that the infection can’t be passed on from kissing.
Having multiple sexual partners and/or STIs also increases the risk of HIV infection through sex if you are not using other protection.
Condoms are the most effective way of preventing transmission of HIV and other STIs.
They can be used during vaginal and anal sex as well as on a penis during oral sex. They should be put on before any sexual contact as HIV can be passed on through pre-cum, vaginal fluid, and from anal mucus.
Both internal (female) and external (male) condoms are available so you can experiment and use whichever works best for you.
Pre-exposure prophylaxis (PrEP)
PrEP is a pill taken by HIV-negative people to prevent HIV. It contains antiretroviral drugs that stop the virus from taking hold in your body.
PrEP is taken by people who have a higher risk of getting HIV, this can include people in a relationship with someone living with HIV, or people who belong to groups who are more at-risk of HIV infection — such as men who have sex with men, and young women in many countries in Southern Africa.
Ask a healthcare professional if you want to know if PrEP would be right for you. PrEP is not currently available everywhere, but access is expanding.
When taken properly PrEP virtually eliminates the risk of getting HIV. PrEP won’t protect you against other sexually transmitted infections (STIs) such as hepatitis C. Condoms are still the best protection from these STIs.
Antiretroviral treatment (ART) lowers the amount of HIV in your body, making it less ly that you will pass HIV on.
If you are living with HIV, are on effective treatment, and have an ‘undetectable’ viral load, it means you have such a low amount of HIV in your body, that you cannot pass HIV on through sex.
If you are HIV-negative, you cannot get HIV from sex with someone who is HIV-positive and undetectable.
Not everyone on HIV treatment has an undetectable viral load, so to be sure that you are ‘undetectable’ (and stay undetectable) you must attend regular viral load monitoring.
Lubricants, or lube, make sex safer by reducing the risk of tears or damage to the vagina or anus caused by dryness or friction. It can also reduce the risk of a condom breaking.
Lube is particularly important for anal sex, as the anus is delicate and does not self-lubricate.
Use water-based lubricants instead of oil-based lubricants, as oil-based lubricants (such as Vaseline) weaken the latex in condoms and can cause them to break.
A dental dam is a small plastic sheet that can be used to cover the mouth, vagina or anus during oral sex to reduce the risk of STIs.
Post-exposure prophylaxis (PEP)
PEP is a course of antiretroviral medicines that can prevent HIV after an event that might have put you at risk of infection, for example if you have had sex without a condom with someone of unknown HIV status.
PEP can stop HIV infection, but it must be started within 72 hours of possible exposure.
Un condoms or PrEP, PEP should not be relied upon as a regular form of protection.
Your doctor or healthcare professional will advise you on whether you could take PEP. PEP may not be available where you are.
Testing for HIV
Knowing your HIV status is an important part of looking after your sexual health and can help you to have safer-sex. If you know you’re positive you can take ART to stay healthy and reduce the risk of transmitting HIV, or if you’re negative, knowing your status can give you more motivation to protect your sexual health.
It’s important to have regular check-ups for other sexually transmitted infections (STIs) as well, as having an STI increases your chance of getting HIV.
Photo credit: Copyright AVERT
Ways HIV Can Be Transmitted
How is HIV passed from one person to another?
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.
Can I get HIV from anal sex?
You can get HIV if you have anal sex with someone who has HIV without using protection ( 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.
Can I get HIV from vaginal sex?
You can get HIV if you have vaginal sex with someone who has HIV without using protection ( 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.
Can HIV be transmitted from a mother to her baby?
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%.
Can I get HIV from sharing needles, syringes, or other drug injection equipment?
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 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.
What are some rare ways that HIV has been transmitted?
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 Giardia, and bacteria Shigella, Salmonella, Campylobacter, and E. coli.
- The most ly 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 unly 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 ly 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.
Risk of exposure to HIV/AIDS
This information was provided by CATIE (the Canadian AIDS Treatment Information Exchange). For more information, contact CATIE at 1-800-263-1638.
Service providers working in HIV prevention are often asked by their patients and clients about the risk of HIV transmission from an exposure to HIV through sex. What do the latest studies tell us about this risk? And how should we interpret and communicate the results?
Challenges in calculating a number
It isn't easy for researchers to calculate the risk of transmission from an exposure to HIV through sex. To do this effectively, a group of HIV-negative individuals need to be followed over time and their exposures to HIV—both the number of times they are exposed and the types of exposure—need to be tracked.
As you can imagine, accurately tracking the number of times a person is exposed to HIV is very difficult.
Researchers ask HIV-negative individuals enrolled in these studies to report how many times they have had sex in a given period of time, what type of sex they had, how often they used condoms and the HIV status of their partner(s).
Because a person may have trouble remembering their sexual behaviour or may not want to tell the whole truth, this reporting is often inaccurate.
Furthermore, a person does not always know the HIV status of their partner(s). For this reason, researchers usually enroll HIV-negative individuals who are in stable relationships with an HIV-positive partner (also known as serodiscordant couples). Researchers can then conclude that any unprotected sex reported by a study participant counts as an exposure to HIV.
Several studies have aimed to estimate the average risk of HIV transmission from a specific type of unprotected sex (for example, vaginal/anal/oral; insertive/receptive).
Due to the difficulties of calculating this risk, these studies have produced a wide range of numbers.
To come up with a more accurate estimate for each type of unprotected sex, some researchers have combined the results of individual studies into what is known as a meta-analysis.
All exposures are not equal
The results of several meta-analyses suggest that some types of sex carry on average a higher risk of HIV transmission than others. Below are estimates from meta-analyses that have combined the results of studies conducted in high-income countries. For types of sex where meta-analysis estimates do not exist, numbers from individual studies are provided.
A meta-analysis exploring the risk of HIV transmission through unprotected anal sex was published in 2010.
1 The analysis, the results of four studies, estimated the risk through receptive anal sex (receiving the penis into the anus, also known as bottoming) to be 1.4%.
(This means that an average of one transmission occurred for every 71 exposures.) This risk was similar regardless of whether the receptive partner was a man or woman.
No meta-analysis estimates currently exist for insertive anal sex (inserting the penis into the anus, also known as topping) but two individual studies were conducted to calculate this risk. The first, published in 1999, calculated the risk to be 0.06% (equivalent to one transmission per 1,667 exposures).
2 However, due to the design of the study, this number ly underestimated the risk of HIV transmission. The second study, published in 2010, was better designed and estimated the risk to be 0.11% (or 1 transmission per 909 exposures) for circumcised men and 0.62% (1 transmission per 161 exposures) for uncircumcised men.
A meta-analysis of 10 studies exploring the risk of transmission through vaginal sex was published in 2009.4 It is estimated the risk of HIV transmission through receptive vaginal sex (receiving the penis in the vagina) to be 0.08% (equivalent to 1 transmission per 1,250 exposures).
A meta-analysis of three studies exploring the risk from insertive vaginal sex (inserting the penis into the vagina) was estimated to be 0.04% (equivalent to 1 transmission per 2,500 exposures).4
No meta-analysis estimates exist for oral sex (vaginal or penile) because too few good-quality studies have been completed.
This is because it is difficult to find people whose only risk of HIV transmission is unprotected oral sex.
A review of the studies that are available was published in 2008 and concluded that vaginal and penile oral sex pose a «low but non-zero transmission probability.»5
In the three studies aimed at calculating the risk of HIV transmission from one act of oral sex, no transmissions were observed among three different populations—lesbian serodiscordant couples, heterosexual serodiscordant couples and single gay men—who reported unprotected oral sex as their only risk for HIV transmission. However, these studies enrolled only a small number of people and followed them for only a short period of time, which may explain the lack of HIV transmissions and makes it impossible to conclude that the risk from oral sex is zero.