A person can transmit HIV through blood, semen, and breast milk. However, HIV cannot survive in saliva, so there is no risk of contracting HIV through kissing.
HIV is a virus that weakens the immune system, which can leave the body vulnerable to infections and diseases.
A person can transmit HIV through certain bodily fluids, such as blood, semen, and breast milk. HIV cannot survive in other body fluids, such as saliva, tears, or sweat unless blood containing HIV is also present.
This means that people are not at risk of contracting the virus if they kiss someone who has HIV.
This article will debunk the myth that people can contract HIV through kissing. We also discuss how HIV is and is not transmitted.
Can a person transmit HIV through kissing?
A person cannot transmit HIV through kissing because the virus is not present in saliva.
HIV can enter the body through damaged areas in the mucous membranes lining the vagina and the rectum. The mouth also contains mucous membranes, but they do not contain cells that are vulnerable to HIV, such as those present in the vagina and rectum.
Saliva contains several proteins and enzymes that serve many different functions, such as beginning the digestion process, assisting in mouth lubrication, and even fighting off germs.
Secretory leukocyte protease inhibitor (SLPI) is an enzyme present in saliva, mucus, and seminal fluid. SLPI prevents HIV from infecting monocytes and T cells, which are types of white blood cell and part of the immune system.
Saliva contains much higher concentrations of SLPI than vaginal and rectal fluids. This may explain why HIV is mostly present in body fluids other than saliva.
Kissing a person living with HIV will not put someone at risk of contracting HIV. According to the Centers for Disease Control (CDC), a person cannot transmit HIV through saliva or closed-mouth kissing.
However, the CDC also state that in extremely rare cases, a person can transmit HIV through “deep, open-mouth kissing if both partners have sores or bleeding gums and blood from the HIV-positive partner gets into the bloodstream of the HIV-negative partner.”
How HIV is transmitted
The only way a person can contract HIV is through direct contact with body fluids that contain HIV. Body fluids that contain HIV can include:
- pre-seminal fluid
- rectal fluids
- vaginal fluids
- breast milk
Below, we discuss the primary modes of HIV transmission:
HIV transmission can occur during anal or vaginal sex without the use of a condom. There have been cases of HIV transmission through oral sex but the risk of this extremely low.
HIV transmission during sex occurs when body fluids containing HIV come into direct contact with mucous membranes or damaged tissue. Anal sex has a higher risk of HIV transmission than vaginal sex because the tissues that line the anus are more prone to damage and bleeding.
It is important to note that effective HIV treatment can reduce a person’s viral load to undetectable levels. This means that people who are taking HIV medications correctly and achieve and maintain an undetectable viral load have effectively no risk of transmitting HIV through sex.
A person can contract HIV through using needles or syringes in which HIV is present. According to the CDC, HIV can live in a used needle for up to 42 days. This is why it is best to avoid sharing needles with anyone.
Pregnancy and breastfeeding
A woman can pass on HIV to a fetus during pregnancy, birth, or breastfeeding. However, HIV treatment significantly lowers the risk of transmitting HIV to the baby.
According to the World Health Organization (WHO), mother-to-child transmission rates range from 15 to 45 percent in the absence of any intervention. However, effective HIV treatment during pregnancy, labor, delivery, and breastfeeding can reduce the risk of transmission to less than 5 percent.
How HIV is not transmitted
Most kinds of physical contact, including holding hands and hugging, do not cause transmission of HIV.
HIV cannot survive long outside of the human body. This means that people cannot contract HIV from touching objects or surfaces that a person living with HIV handles.
Nor can someone transmit HIV through holding hands, hugging, or touching other people. It is important to remember that HIV transmission requires an exchange of body fluids that contain HIV.
HIV transmission can also not occur through:
- air or water
- mosquitoes, ticks, or other insects
- saliva, tears, or sweat, unless they also contain blood from a person living with HIV
- scratching, biting
- casual contact, such as hugging, shaking hands, or kissing
- mutual masturbation
- sharing food or drinks
- sharing toilet seats, dishes, or other objects
There are no known cases of anyone contracting HIV from a tattoo or body piercings. However, it is possible to contract HIV from a reused needle or improperly sanitized equipment.
Many unfounded myths surround the transmission of HIV. However, a person can only transmit HIV through certain body fluids that contain HIV, such as blood, semen, and breast milk.
HIV cannot survive outside the body and is not present in other body fluids such as saliva, tears, or sweat. This means that a person cannot contract HIV through kissing, touching, hugging, or sharing toilet seats, foods, or drinks with someone living with HIV.
The primary mode of HIV transmission is through vaginal or anal sex without a condom. However, people who are taking HIV medications correctly and achieve and maintain an undetectable viral load have effectively no risk of transmitting HIV through sex.
Medically reviewed by Deborah Weatherspoon, Ph.D., R.N., CRNA
Written by Jamie Eske