If you or a loved one is living with HIV, you may wonder how the virus can (and can’t) be spread from one person to another. There are plenty of myths and misunderstandings about how HIV is transmitted. Some people, for instance, may wonder if the exchange of bodily fluids when sharing drinks or kissing could potentially transmit the virus.

Here is what you need to know about how HIV spreads, including whether a kiss or a shared drink can transmit the virus from someone who is HIV-positive to someone who is not. Understanding how HIV is transmitted can equip individuals to take the proper precautions to prevent spreading the virus, and it can help alleviate the stigma and misunderstanding surrounding HIV.

What Is HIV?

HIV is a type of virus known as a retrovirus — it infects certain cells in the immune system. Over time, these cells can no longer do their jobs, and the immune system can’t properly fight off harmful invaders such as bacteria and other viruses. A deficient immune system makes a person more susceptible to diseases, infections, and cancers that they might otherwise be unlikely to develop.

How Is HIV Spread?

HIV is transmitted when an uninfected person comes into direct contact with certain bodily fluids from someone who is HIV-positive (infected with the virus). These fluids include:

• Vaginal fluids
• Semen
• Pre-seminal fluid
• Blood
• Breast milk
• Rectal fluid

For HIV to spread, the virus in these fluids has to not only touch or come close to another person but also enter their bloodstream. This transmission can happen through mucous membranes (found in the mouth, rectum, and genitals), cuts and scrapes, or by injection.

HIV can also be transmitted via contact with cerebrospinal, amniotic, or synovial (joint) fluid. However, this type of transmission is uncommon and is most likely to occur in health care settings.

What Does Not Spread HIV?

A great deal of stigma continues to surround HIV, partly due to prevailing misunderstandings about how the condition can be spread. As one myHIVteam member summed it up: “There is still stigma in every community, city, state, and the whole nation. Disinformation is one of the problems that keeps the stigma.”

Clearing up incorrect ideas about how HIV is transmitted could help reduce the stigma.

As explained above, although mucous membranes are found in the mouth — where saliva is produced — the virus cannot be transmitted through contact with the saliva of someone living with HIV. Although the virus is detectable in saliva, the fluid contains both enzymes and antibodies that prevent the virus from spreading to other cells.

This means that HIV will not be passed to an uninfected person through, say, mouth-to-mouth resuscitation or:

• Most kissing (more on that later)
• Sharing a drink, a plate, or silverware
• Using the same toothbrush
• Being sneezed or coughed on by someone with HIV

Note that open-mouth kissing and “deep” kissing will rarely transmit HIV. When both partners have bleeding gums, open wounds, or open sores in their mouths, transmission can occur — but not through saliva itself. Instead, blood from one partner’s open wound makes its way into the other partner’s wound, transmitting the virus. However, HIV transmission in this manner seldom occurs.

Aside from saliva, several other body fluids — feces, urine, tears, and sweat — also do not spread HIV from one person to another. This means HIV can’t be contracted from:

• Changing a diaper on a child or adult with HIV
• Using the same exercise equipment
• Sharing a toilet seat
• Comforting someone when they are crying

HIV also can’t survive well outside the body. The virus doesn’t live long or reproduce on surfaces or outside of a human host, so it can’t be spread through:

• Hugging or shaking hands
• Closed-mouth kissing
• Touching (even intimate touching)
• Being bitten by insects such as ticks and mosquitoes

Because of high medical standards in developed countries and prevalent HIV testing, it’s extremely unlikely for the virus to be contracted from a blood transfusion or in a medical setting.

Finally, you cannot transmit or catch HIV infections through any sort of casual contact or interaction. This means that the virus can’t be spread in saunas or swimming pools or while giving or receiving piercings or tattoos (as long as basic hygiene procedures are followed).

Overall, outside of participating in certain activities, you shouldn’t have to worry about getting HIV or giving it to someone else. Additionally, you can take steps to lower the risk of contracting or transmitting the virus during sexual activities.

How To Reduce Your Chances of Catching or Transmitting HIV

The most common ways of transmitting HIV involve sharing drug injection apparatuses (used needles or syringes) and having vaginal or anal sex. Whether you are concerned about getting or transmitting HIV, you can take a few preventive measures.

Prevent Contracting HIV

If you are HIV-negative, one of the best ways to reduce your risk of contracting the virus is to avoid injection drug use. If you do use IV drugs, you can take harm-reduction measures, such as using clean needles each time and never sharing needles, to prevent picking up or spreading HIV.

Used correctly, condoms are highly effective at preventing HIV transmission through having vaginal or anal sex. In addition, you can make sure any sexual partners recently tested negative for HIV or, if they are HIV-positive, have an undetectable viral load. Even if a person has tested negative or has an undetectable viral load, it’s important to consider using condoms to lower the risk of contracting other sexually transmitted infections (STIs) like chlamydia or gonorrhea.

The very low risk of HIV transmission through oral sex can be further reduced by using a condom or dental dam.

If an intimate partner has been diagnosed with HIV — and especially if their HIV is not undetectable for at least six months straight during treatment — taking PrEP (preexposure prophylaxis) can protect you. These medications help prevent HIV infection even if you are exposed to the virus. If you are not on PrEP, you can take post-exposure prophylaxis (PEP) within 72 hours of exposure.

Prevent Transmitting HIV

If you are HIV-positive, you can help lower your risk of HIV transmission by paying attention to your viral load. This number tells you how much of the virus is present and detectable in your body at any given time. Most people can get their load so low that it is undetectable with modern antiretroviral (ART) HIV treatments, usually within three months to six months of starting the medication.

The best way to achieve an undetectable viral load is to take your HIV medications exactly as directed. Your health care provider can monitor your viral load through blood tests at regular intervals. Talk to your doctor about how frequently you need to be seen, which may vary depending on if you recently started a new medication or are on one that has been working well for a while.

If you have an undetectable viral load for at least six consecutive months while taking ART consistently, you won’t transmit the virus during sex. However, people with an undetectable viral load are still advised to consider using condoms to protect against transmitting or contracting other STIs, especially if they have multiple sexual partners. If you are in a monogamous relationship and have an undetectable viral load, you and your partner might consider having sex without condoms — but you should also discuss this possibility with your health care provider.

Find Your HIV Team Today

Are you or a loved one living with HIV? Consider joining myHIVteam today. Here, more than 35,000 people come together to connect with others who understand life with HIV. You can share your story, join ongoing conversations, and find a team made up of people from around the world who will support you through your journey.

Do you have questions about how HIV is transmitted? Have others asked you how HIV is spread? Share your questions or thoughts in the comments below or by posting on myHIVteam.