How Do You Get HIV?

Medically Reviewed by Zilpah Sheikh, MD on August 12, 2024
7 min read

We've come a long way from the days when people were so worried they might get HIV that they completely avoided people with it. Still, some people may not be sure exactly what's safe and what's not.

If there's a question or a concern, pre-exposure prophylaxis (PrEP) is an important option for those at risk of exposure to HIV through sexual or drug-use behaviors.

HIV is a virus, like a cold or the flu, but it doesn't spread the same way. In fact, it's a lot harder to get. You can get it only when certain fluids from an HIV-infected person get into your body.

So, how does that happen?

No. HIV is spread only through specific body fluids: blood, semen, pre-seminal fluid (secreted from the penis before ejaculation), vaginal and rectal fluid, and breast milk. Hugging and shaking hands are safe.

It's possible, but it hardly ever happens. HIV isn't spread through saliva.

But if you kiss someone who's infected and has bleeding gums or sores, you could get the virus if you also have cuts or sores around or in your mouth — because of the blood-to-blood contact.

No. Some viruses, such as the common cold and COVID-19, can travel through the air. But HIV is not an airborne virus.

No, contact with someone else's tears, sweat, vomit, or pee doesn't expose you to HIV. Sweat and tears don't carry HIV. Vomit and pee might have traces of blood, which does carry HIV, but there have been no reported cases of HIV from vomit or pee.

Either partner can get HIV this way.

HIV can enter your body through the tissue that lines your vagina and cervix. The virus can also enter through the opening of your penis or a small cut or sore on it. The partner who is penetrated generally has a higher risk of infection.

Effective HIV drugs (antiretroviral therapy) will greatly reduce the chances that an HIV-infected person can give HIV to their partner in this way. However, even when HIV drugs are used, use a condom to cut the chances of exposure to the virus. It also will help protect against other sexually transmitted infections.

Either partner can get it from the other, but the person being penetrated is at a higher risk.

Although condoms work to protect you if they stay in place, they're more likely to break during anal sex. It's smart to use a condom-safe lubricant (that is not oil-based) to reduce friction and the risk of condoms breaking.

Again, effective antiretroviral therapy in the HIV-infected partner will reduce the chances of passing HIV. However, condoms should still be used to prevent HIV and other sexually transmitted infections.

It's much less likely than when you have anal or vaginal sex. Still, it can happen.

The person who ends up with semen or vaginal fluid in their mouth is at a greater risk. Again, use a condom, latex barrier, or dental dam.

No. First, there's not likely to be the right kind of body fluid on such a surface. And if there were, the virus would probably die before you got to it; it can't live long outside a body. And it still would have to get through your skin or into you somehow.

No. Sharing dishes, glasses, and eating utensils is safe. Remember, HIV isn't in saliva, and it dies quickly once it's outside the body.

Yes, it's safe, even if there are traces of blood or another fluid in the food. The virus can't survive the cooking process or your stomach acid.

Passing HIV through eating has happened only in rare cases, when children ate food that was already chewed by someone with the virus. The CDC says it has no reports of HIV transmission through restaurant food.

No. When HIV first began to spread, there were concerns that mosquitoes might transmit the virus. But studies by the CDC and other organizations have found no evidence that insects transmit HIV. Even in areas of the world where HIV is widespread and there are lots of mosquitoes, experts have not found an outbreak related to insects.

Studies of insect biting behavior found that when an insect bites you, it doesn't inject its own blood or the blood of a person or animal previously bitten. It injects saliva, which helps it feed on your blood more easily.

Even if an insect bites an HIV-infected person or animal, the virus doesn't live for long inside the insect, and the virus doesn't multiply inside insects. That keeps insects from becoming infected with HIV and transmitting it.

It's not just the needles. Any of the supplies for preparing drugs for injection — syringes, bottle caps, spoons, or containers — could transmit the virus if someone with HIV used it first.

In theory, yes, if the needles were used on someone with HIV before you and not sterilized. But the CDC says no cases have been reported of someone getting the virus this way.

Yes, HIV can be transmitted through blood transfusion if the virus is present in the blood. This happened when HIV first became prevalent. But new procedures have dramatically lowered the risk, especially in the U.S. Those changes include stricter rules on who can donate blood and checking blood donations for HIV antibodies.

The risk of getting HIV through blood transmission in the U.S. is extremely low.

Maybe. Body fluids such as blood can pass through broken skin, wounds, or mucous membranes. But it's very rare.

It's possible if a bite or scratch breaks your skin, but (yes, again) it's extremely rare. And if your skin doesn't break, there's no chance.

Getting spit on is unpleasant and messy, but it's not a danger as far as getting HIV.

Someone infected with HIV can pass the virus to their child during pregnancy , while they are giving birth, or through their breast milk. 

The virus can cross the placenta, infecting the baby through the mother's blood. A baby also might be exposed to infected fluids during delivery. HIV can also be present in breast milk, posing a risk if the baby has oral sores.

The chances are greatly reduced, however, by taking effective HIV drugs (antiretroviral therapy) throughout pregnancy, labor, and delivery. Other steps you can take to protect your baby include giving your baby anti-HIV medicine after birth and opting for a C-section delivery if lab tests show the levels of virus in your body are high. You also might choose not to breastfeed.

Acquired immunodeficiency syndrome, or AIDS, is the last stage of HIV infection. Not everyone who has HIV will progress to that stage.

There's no cure for HIV. But advances in medical knowledge, treatment, and public understanding have made it a manageable chronic health condition.

Antiretroviral medicines can prevent an HIV infection from progressing to AIDS. These drugs keep the virus from reproducing itself -- called replicating -- inside your body.

The amount of HIV found in your body is called your "viral load." During your treatment, your blood will be checked regularly to see what your viral load is. When it drops to a point where doctors can no longer measure it, your viral load is called "undetectable." Most people with HIV reach undetectable status within 6 months of beginning antiretroviral treatment.

HIV is a virus just like the cold or flu, but it's not as easy to transmit. The virus is carried only by certain body fluids, such as blood, semen, pre-seminal fluid, vaginal and rectal fluid, and breast milk. Even if you come in contact with those fluids, the virus still has to find a way into your body. That's usually through open cuts or sores, by direct injection (from a needle or syringe), or through a mucous membrane. Those are found in your rectum, vagina, mouth, or tip of the penis. HIV is not airborne like the cold virus. It doesn't live long outside the human body, so it doesn't infect surfaces. If you get HIV, antiretroviral drugs can keep the virus from reproducing in your body.

How likely is it to get HIV as a woman?

In 2021, about 18% of new HIV infections affected women or those assigned female at birth, according to the CDC. The main way of transmission is sex with a man who has HIV.

How are you most likely to get HIV?

In the U.S., the most common ways HIV spreads are unprotected anal or vaginal sex with a person who has HIV, or through sharing needles and other equipment for injecting drugs. 

How likely is it for a woman to pass HIV to a man?

A woman or someone assigned female at birth can transmit HIV through unprotected vaginal sex, but the risk is low. Experts believe that less than 1 in 1,000 exposures lead to an HIV infection. Certain factors, such as menstruation or an uncircumcised penis, might raise the risk a bit. Things that reduce the risk include using condoms, taking antiretroviral drugs if you have HIV, and taking PrEP, the HIV-prevention drug.

Can you contract HIV from spit?

No. HIV isn't present in saliva.