How Do You Get HIV?

Written by Kara Mayer Robinson, Alicia Racelis, PhD
Medically Reviewed by Shruthi N, MD on October 15, 2025
8 min read

We've come a long way since HIV was first discovered. 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 and acts a lot like other STDs. 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 fluid
  • Rectal fluid
  • Breast milk

Hugging and shaking hands are totally safe.

It's possible, but it hardly ever happens because you'd both have to have blood-to-blood contact around or in your mouth. 

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 an open sore. So to catch it, you'd also need to have cuts or sores around or in your mouth, since blood-to-blood contact would be needed to transmit HIV.

No. Some viruses, such as the common cold and COVID-19, can travel through the air. But HIV can't travel through the air (it isn't airborne).

No, you can't get HIV from someone else's tears, sweat, vomit, or pee.

Sweat and tears don't carry HIV. 

Vomit and pee might have traces of blood, which may carry HIV, but there have been no reported cases of HIV from vomit or pee.

Either partner can get HIV with vaginal sex. The virus can enter your body through the tissue that lines the vagina and cervix. The partner who is penetrated usually has a higher risk of infection.

Or, the virus can also enter through the opening of your penis or a small cut or sore on it.

How can I lower my HIV infection risk?

HIV medications (antiretroviral therapy or ART) can greatly lower your chances of getting HIV from your sexual partner. ART helps lower HIV levels to "undetectable" in your partner's body. That means the test can't find any HIV and your partner can't pass HIV to you.

And if you take pre-exposure prophylaxis (PrEP) medicine, HIV can't take hold in your body and your risk for HIV infection is lower. You can take PrEP two ways:

  • Daily pills
  • A bimonthly or biyearly injection

If you also use a condom, you'll cut your chances of HIV even more and also protect against other sexually transmitted infections.

Either partner can get HIV from the other, but the person being penetrated has 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 isn't oil-based to lower friction and the risk of condoms breaking.

Again, if your partner has HIV but uses antiretroviral therapy, you'll have a lower risk for HIV infection. And if you take PrEP as your doctor prescribes, you'll lower your HIV risk even further. Use a condom for more protection from 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 has a greater risk. Again, use a condom, latex barrier, or dental dam to prevent getting infected.

No. First, there's not likely to be the right kind of body fluid on such a surface. And if there were, HIV is fragile and would probably die before you got to it. HIV can't live long outside a body and would have to enter through your skin or into your body some other way.

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. In fact, the CDC says there aren't any reports of HIV transmission through food. So there's no risk of getting the virus from eating food.

No. When HIV first began to spread, some questions about mosquitoes transmitting the virus came up. But studies by the CDC and other organizations found no proof of insects transmitting HIV. That's even true in areas of the world where HIV is widespread and there are lots of mosquitoes.

Studies of insect biting behavior found that the insects don't inject their own blood, or blood from other people or animals that they've bitten before you. Mosquitoes inject saliva to help them feed on your blood, and HIV can't live in saliva.

Even if an insect bites an HIV-infected person or animal, the virus doesn't live for long inside the insect. And the virus can't make copies of itself inside a mosquito either. 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 can transmit HIV if someone with HIV uses it first, such as:

  • Syringes
  • Bottle caps
  • Spoons
  • Containers

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.

No, the risk of getting HIV through blood in the U.S. is extremely unlikely because of strict testing.

In the past, HIV was transmitted through a blood transfusion if the virus was present in the donated blood. This happened a long time ago, when HIV first became prevalent and the testing procedures were not as strict. But new procedures in the U.S. now include:

  • Stricter rules on who can donate blood
  • Checking blood donations for HIV antibodies
  • Testing blood donations for the HIV genetic code (nucleic acid testing)

Maybe. But you'd also have to have an open wound or cut. Body fluids such as blood can pass through broken skin, wounds, or mucous membranes. But that'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.

Without treatment, 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.

Today, less than 1% of babies get HIV from their mother because of antiretroviral therapy (ART). If you have HIV and are thinking about pregnancy, taking ART can protect your baby from HIV. 

You'll take ART throughout your pregnancy, labor, and delivery. Other steps you can take to protect your baby include giving your baby anti-HIV medicine after birth. You can also opt for a cesarean section delivery if lab tests show the levels of virus in your body are high. You might also choose not to breastfeed, talk to your doctor about what's best.

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

Although there's no cure for HIV, yet, advances in medical knowledge, treatment, and public understanding have made it a manageable chronic health condition. ART can prevent an HIV infection from progressing to AIDS. These medicines keep the virus from making copies of itself – called replicating – inside your body.

The amount of HIV found in your body is called your "viral load." During your treatment, regular blood tests check your viral load. When it drops to a point where doctors can't find any HIV in your blood, it's called "undetectable." Most people with HIV reach undetectable status within six months of starting ART.

HIV is a virus only found and transmitted in certain body fluids such as breast milk, blood, semen, pre-seminal fluid, and vaginal and rectal fluids. HIV usually spreads through unprotected sex or injection drug use, but less often through breast milk. Antiretroviral therapy (ART) can help prevent HIV spreading to your partner, and pre-exposure prophylaxis (PrEP) can lower your partner's risk of HIV. Talk to your doctor about the best option for you and your partner to stay healthy together.

How likely is it to get HIV as a woman?

In 2021, about 18% of new HIV infections impacted 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?

Experts think that fewer than 1 out of 1,000 exposures can lead to HIV infection in a man who has vaginal sex with someone who is HIV-positive. Certain things, such as menstruation or an uncircumcised penis, might raise the risk a bit. You can lower your HIV risk by using a condom, taking antiretroviral therapy (ART) if you have HIV, or taking PrEP to prevent HIV infection.

Can you contract HIV from spit?

No. HIV can't live in saliva and isn't present in spit.