What is HIV/AIDS?
HIV stands for human immunodeficiency virus. It is the virus that can lead to acquired immunodeficiency syndrome, or AIDS. Unlike some other viruses, the human body cannot get rid of HIV. That means that once you have HIV, you have it for life.
No safe and effective cure currently exists, but scientists are working hard to find one, and remain hopeful. Meanwhile, with proper medical care, HIV can be controlled. Treatment for HIV is often called antiretroviral therapy or ART. It can dramatically prolong the lives of many people infected with HIV and lower their chance of infecting others. Before the introduction of ART in the mid-1990s, people with HIV could progress to AIDS in just a few years. Today, someone diagnosed with HIV and treated before the disease is far advanced can have a nearly normal life expectancy.
HIV affects specific cells of the immune system, called CD4 cells, or T cells. Over time, HIV can destroy so many of these cells that the body can’t fight off infections and disease. When this happens, HIV infection leads to AIDS.
How do people get HIV?
There are many myths about how people get HIV. HIV can only be spread by the blood, semen (cum), pre-seminal fluid (pre-cum), rectal fluids, vaginal fluids, or breast milk of someone living with HIV. To get HIV, the fluids must come in contact with a mucous membrane or damaged tissue, or be directly injected into the bloodstream (by a needle or syringe). Mucous membranes can be found inside the rectum, the vagina, the opening of the penis, and the mouth.
Most women get HIV by having sex. However, in the United States, HIV is most often spread by:
- Having sex with someone who has HIV. In general:
- Anal sex is the highest-risk sexual behavior.
- Vaginal sex is the second highest-risk sexual behavior.
- Having multiple sex partners or having other sexually transmitted infections can increase the risk getting HIV through sex.
- Sharing needles, syringes, rinse water, or other equipment (works) used to prepare injection drugs with someone who has HIV.
Less commonly, HIV may be spread by:
- Oral sex—using the mouth to stimulate the penis, vagina, or anus (fellatio, cunnilingus, and rimming). Giving fellatio (mouth to penis oral sex) and having the person ejaculate (cum) in your mouth is riskier than other types of oral sex.
- Being born to a mother who has HIV. HIV can be passed from a mother to a child during pregnancy, birth, or breastfeeding.
- Being stuck with an HIV-contaminated needle or other sharp object. This is a risk mainly for health care workers.
- Receiving blood transfusions, blood products, or organ/tissue transplants that are contaminated with HIV. This risk is extremely small because of rigorous testing of the U.S. blood supply and donated organs and tissues.
- Eating food that has been pre-chewed by an HIV-infected person. This is very rare, but contamination can occur when infected blood from a caregiver’s mouth mixes with food while chewing.
- Being bitten by a person with HIV. There have only been a small number of documented cases of someone getting HIV from a bite. In each case, they were severe bites with extensive tissue damage and the presence of blood. There is no risk of getting HIV if the skin is not broken.
- Contact between broken skin, wounds, or mucous membranes and HIV-infected blood or blood-contaminated body fluids. These reports have also been extremely rare.
- Deep, open-mouth kissing if the person with HIV has sores or bleeding gums and blood is exchanged. HIV is not spread through saliva. Transmission through kissing alone is extremely rare.
HIV does not survive long outside the human body (such as on surfaces), and it cannot reproduce. HIV is not spread by:
- Air or water.
- Insects, including mosquitoes or ticks.
- Saliva, tears, or sweat. There is no documented case of HIV being transmitted by spitting.
- Casual contact like shaking hands or sharing dishes.
- Closed-mouth or “social” kissing.
- Toilet seats.
I don’t think I’m at risk for HIV. Why should I get tested?
Many people who have tested positive for HIV did not think they were at risk for HIV. CDC recommends that everyone between the ages of 13 and 64 be tested for HIV at least once as part of routine medical care.
Even if you have been in a long-term relationship with one person, you should find out for sure whether you or your partner has HIV. If you are both HIV-negative and you both remain faithful (monogamous) and do not have other risks for HIV infection, then you probably won’t need another HIV test unless your situation changes.
How can I protect myself from HIV?
Staying healthy is important. Knowing your HIV status gives you powerful information to help you take steps to keep you and your partners healthy. You should get tested for HIV, and encourage your partners to get tested too. If you test positive for HIV, treatment can help you stay healthy for many years and reduce your chances of passing HIV to your sex partners. To find a testing site near you, use the testing site locator on this page, call 1-800-CDC-INFO (232-4636), text your ZIP code to KNOW IT (566948), or use a home testing kit.
If you are sexually active, there are more tools available today to prevent HIV than ever before. The list below provides a number of ways that you can lower your chances of getting HIV. The more of these actions you take, the safer you can be.
- Choose less risky sexual behaviors. Oral sex is much less risky than anal or vaginal sex. Anal sex is the highest-risk sexual activity. Sexual activities that do not involve the potential exchange of bodily fluids carry no risk for getting HIV (e.g., touching). Learn more about HIV risk.
- Use condoms consistently and correctly.
- Reduce the number of people you have sex with. The number of sex partners you have affects your HIV risk. The more partners you have, the more likely you are to encounter someone with HIV whose viral load is not suppressed, or to have a sex partner with a sexually transmitted disease. Both of these factors can increase the risk of HIV.
- Talk to your doctor about pre-exposure prophylaxis (PrEP). PrEP is a prevention option for people who are at high risk of getting HIV. It’s meant to be used consistently, as a pill taken every day, and to be used with other options to prevent the spread of HIV, like condoms. You should consider PrEP if you are HIV-negative and in an ongoing sexual relationship with an HIV-positive partner. PrEP should also be considered if you do not regularly use condoms during sex and are having sex with someone whose HIV status you don’t know for sure, or who may be at substantial risk of getting HIV (e.g., people who inject drugs or men who have sex with other men).
If you ever think you may have been potentially exposed to HIV, talk to your doctor right away (within 3 days). Medicines such as post-exposure prophylaxis (PEP) can help. PEP is the use of taking antiretroviral drugs (or HIV treatment) after a single high-risk event to stop HIV from making copies of itself and spreading through your body. PEP must be started as soon as possible to be effective—and always within 3 days of the incident that could have exposed you to HIV. If you think you may have been exposed to HIV very recently, see a doctor as soon as possible to find out if PEP is right for you. An example of a possible exposure is if you have anal or vaginal sex without a condom with someone who is or may be HIV-positive and you are HIV-negative and not taking PrEP. Starting PEP immediately and taking it daily for 4 weeks reduces your chance of getting HIV.
- Get tested and treated for other STDs and encourage your partners to do the same. If you are sexually active, get tested for HIV and other STDs at least once a year. STDs can have long-term health consequences. They can also increase your chance of getting HIV or giving it to others. Use our HIV testing site locator to find free, fast and confidential testing sites near you.
- If your partner is HIV-positive, encourage him to get and stay on treatment. HIV treatment also known as antiretroviral therapy (ART) reduces the amount of HIV virus (viral load) in blood and body fluids. ART can keep people with HIV healthy for many years, and reduce the chance of passing HIV to sex partners by nearly 96% if taken consistently and correctly.
When should I get tested for HIV?
The immune system usually takes 3 to 8 weeks to make antibodies against HIV, but HIV tests differ in how early they are able to detect antibodies. Although most HIV tests look for these antibodies, some look for the virus itself. The period after infection but before the test becomes positive is called the window period.
Deciding when to get tested therefore depends on when you may have been exposed and which test is used. You can ask your health care provider about the window period for the HIV test you are taking. If you are using a home test, you can get that information from the materials included in the packaging of the test.
A few people will have a longer window period, so if you get a negative antibody test result in the first 3 months after possible exposure, you should get a repeat test after 3 months. Ninety-seven percent of people will develop antibodies in the first 3 months after they are infected. In very rare cases, it can take up to 6 months to develop antibodies to HIV.
Between the time you were possibly exposed and when you receive your test results:
Don’t have sex—or always use a condom if you do.
Don’t inject drugs—or always use clean equipment and don’t share needles or other equipment (works).
It is also important to see your doctor immediately if you have had sex with someone who has or may have HIV. Starting medication known as post-exposure prophylaxis, or PEP, within three days after a possible exposure reduces your chance of getting HIV.
I know sex with a man is risky, but what about having sex with a woman?
Women have little to no risk of getting HIV from having sex with other women.
I’m pregnant or thinking about getting pregnant. Should I get tested for HIV?
HIV testing during each pregnancy is important. If your result is positive, treatment can improve your health and greatly lower the chance that you will pass HIV to your infant before, during, or after birth. HIV treatment is most effective for protecting your baby from HIV when started as early as possible during pregnancy. However, there are still great health benefits to starting preventive treatment even during labor or shortly after the baby is born.
CDC recommends that all pregnant women be screened for HIV. You should ask to get tested for HIV. Ask your doctor about HIV or for written materials about HIV. Your doctor can also help you determine if you have risk factors for HIV and refer you to HIV prevention counseling.
For heterosexual couples where one partner has HIV and the other does not, PrEP is one of several options that can help prevent the uninfected partner from getting HIV during conception and pregnancy.
Can I get HIV from oral sex?
Oral sex involves giving or receiving oral stimulation to the penis (fellatio), the vagina (cunnilingus), or the anus (anilingus or rimming). Most types of oral sex carry little risk of HIV. The highest oral sex risk is performing oral sex (fellatio) with ejaculation in your mouth. However, the risk is still low, and much lower than anal or vaginal sex. Factors that may increase the risk of transmitting HIV through oral sex are oral ulcers, bleeding gums, genital sores, and the presence of other sexually transmitted diseases (STDs) (which may or may not be visible).
The following things can reduce your risk of getting HIV through oral sex:
- Avoid having your partner ejaculate in your mouth.
- Use barriers such as condoms, natural rubber latex sheets, dental dams, or cut-open non-lubricated condoms.
Your chance of getting HIV from oral sex is lower if you are already taking pre-exposure prophylaxis (PrEP) consistently and correctly or if your partner is living with HIV and is taking antiretroviral therapy (ART) consistently and correctly.
Keep in mind that barrier methods, such as condoms, are the only way to protect you from some STDs, including gonorrhea of the throat. Although the chance of getting or transmitting HIV from anilingus/rimming (oral-anal contact) is small, there is a big chance of passing hepatitis A and B, parasites, and other bacteria to the partner who is doing the rimming. There are effective vaccines that protect against hepatitis A and B and human papillomavirus infections. Talk to your doctor to see if these are right for you, if you have not already been vaccinated.
How can I get tested for HIV?
Getting tested for HIV is an important step in taking charge of your life. Regardless of the results, knowing your status puts you in control of your health. If you are not living with HIV, you can commit to making choices to prevent you from getting HIV. If you are living with HIV, you can seek treatment to better manage your health and reduce your risk of passing the virus to others.
HIV testing is free, fast, and confidential. Rapid HIV tests can provide results very quickly — in as little as 20 minutes. Rapid tests have similar accuracy rates as other traditional screening tests. As is true for all screening tests, a positive reactive rapid HIV test result must be confirmed with a follow-up test before a diagnosis can be made. To find an HIV testing location near you, use the Take Charge. Take the Test.™ site locator on this page, or call 800-CDC-INFO (800-232-4636). You can also buy a home testing kit online or at a pharmacy.
There are several different types of tests used to detect HIV. The most common HIV test is the antibody screening test (immunoassay), which tests for the antibodies that your body makes against HIV. The immunoassay may be conducted in a lab or as a rapid test at the testing site. It may be performed on blood or oral fluid (not saliva).
Because the level of antibody in oral fluid is lower than it is in blood, blood tests tend to find infection sooner after exposure than do oral fluid tests. In addition, most blood-based lab tests find infection sooner after exposure than rapid HIV tests. Newer immunoassay tests can find HIV as soon as 3 weeks after exposure to the virus. Several lab tests now in use can detect antibodies and antigen (part of the virus itself), so find recent infection earlier than tests that detect only antibodies.
The rapid test is an immunoassay used for screening, and it produces quick results, in 20 minutes or less. Rapid tests use blood or oral fluid to look for antibodies to HIV. If an immunoassay (lab test or rapid test) is conducted during the window period (i.e., the period after exposure but before the test can find antibodies), the test may not find antibodies and may give a false-negative result. All immunoassays that are positive need a follow-up test to confirm the result.
Follow-up diagnostic testing is performed if the first immunoassay result is positive. Follow-up tests include: an antibody differentiation test, which distinguishes HIV-1 from HIV-2; an HIV-1 nucleic acid test, which looks for virus directly; or the Western blot or indirect immunofluorescence assay, which detect antibodies.
Immunoassays are generally very accurate, but follow-up testing allows you and your health care provider to be sure the diagnosis is right. If your first test is a rapid test, and it is positive, you will be directed to a medical setting to get follow-up testing. If your first test is a lab test, and it is positive, the lab will conduct follow-up testing, usually on the same blood specimen as the first test.
False-positive tests are rare. If tests are conducted during the window period, they can give a false-negative result.
Currently there are only two home HIV tests: OraQuick In-home HIV test and the Home Access HIV-1 Test System. If you buy your home test online, make sure the HIV test is FDA-approved.
The OraQuick In-Home HIV Test provides rapid results in the home. The testing procedure involves swabbing your mouth for an oral fluid sample and using a kit to test it. Results are available in 20 minutes. If you test positive, you will need a follow-up test. The manufacturer provides confidential counseling and referral to follow-up testing sites. Because the level of antibody in oral fluid is lower than it is in blood, oral fluid tests find infection later after exposure than do blood tests. Up to 1 in 12 people may test false-negative with these tests.
The Home HIV Access HIV-1 Test System is a home collection kit, which involves pricking your finger to collect a blood sample, sending the sample to a licensed laboratory, and then calling in for results a few days later. If the test is positive, a follow-up test is performed right away. This test is anonymous. The manufacturer provides confidential counseling and referral to treatment. The tests conducted on the sample collected at home find infection later than most lab-based tests offered by providers.
RNA tests detect the virus directly (instead of the antibodies to HIV) and thus can detect HIV at about 10 days after infection—as soon as it appears in the bloodstream, before antibodies develop. These tests cost more than antibody tests and are generally not used as a screening test, although your doctor may order one as a follow-up test, after a positive antibody test, or as part of a clinical workup.
Getting tested for HIV is an important step in taking charge of your life. More and more black women are standing up and getting tested for HIV. They are looking out for themselves and doing what they need to do to stay healthy. Regardless of the results, there are treatment and support programs available to help you live a healthy and productive life. To find an HIV testing location near you, use the Take Charge. Take the Test.™ site locator or call 800-CDC-INFO (800-232-4636).
I think I may have been exposed to HIV. Is there anything I can do to reduce the chances of getting HIV?
Post-exposure prophylaxis (PEP) is medicine that is used to prevent HIV after a possible exposure. An example of a possible exposure is if you have sex without a condom with someone who is HIV-positive or whose HIV status you don’t know. You take PEP for 4 weeks if you may have been recently exposed to HIV and are not on PrEP.
PEP keeps HIV from making copies of itself and turning into infection. To be effective, PEP must begin as soon as possible, but always within 72 hours (3 days) of a possible exposure. Keep in mind that PEP should only be used in situations right after a potential exposure. PEP is not intended for long-term use. It is not a substitute for other proven HIV prevention methods, such as correct and consistent condom use.
You should continue to use condoms with sex partners while taking PEP. If you have repeated exposures to HIV, you should consider PrEP.
If I test negative for HIV, does that mean that my boyfriend/sex partner is HIV negative too?
No. Your HIV test result only tells you your HIV status. Just because you test negative for HIV, it doesn’t mean your partner is also HIV negative. HIV is not necessarily transmitted every time you have sex. Therefore, you cannot rely on your HIV test results to determine your partner’s HIV status.
If you don’t know your partner’s HIV status, ask if he has been tested for HIV and when. Then discuss what types of risk behaviors he has engaged in, both currently and in the past and consider getting tested for HIV together.
Is there a pill that can prevent me from getting HIV?
If you have sex with someone who has or may have HIV, talk to your doctor about medicines to prevent HIV infection, known as pre-exposure prophylaxis or PrEP. This may also include HIV-negative women who would like to get pregnant by their HIV-positive partners. PrEP is meant to be used consistently, as a pill taken every day, and to be used with other prevention options such as condoms. When taken consistently, PrEP has been shown to reduce the risk of HIV infection in people who are at high risk by up to 92%. PrEP is much less effective if it is not taken consistently.
It’s important to note that PrEP is NOT a vaccine or a cure. PrEP medication is not injected into the body and does not work the same way as a vaccine. The word “prophylaxis” means to prevent or control the spread of an infection or disease. The goal of PrEP is to prevent HIV infection from taking hold if you are exposed to the virus. This is done by taking a pill that contains two HIV medications every day. These are the same medicines used to keep the virus from growing in people who are already living with HIV.
PrEP is not for everyone. Doctors prescribe PrEP for some patients who have a very high risk of coming in contact with HIV by having sex without a condom with someone who is living with HIV. You should consider PrEP if you sometimes have sex without using a condom, especially if you have a sex partner who you know is living with HIV. You should also consider PrEP if you don’t know whether your partner has HIV but you know they have risks for it (for example, they inject drugs or are having sex with other people in addition to you), or if you have recently been diagnosed with a sexually transmitted infection. If your partner has HIV, PrEP may be an option to help protect you from getting HIV while you try to get pregnant, during your pregnancy, or while breastfeeding.
PrEP can only be prescribed by a health care provider and should be taken as directed. Learn more about PrEP.
What if I test negative for HIV?
The immune system usually takes 3 to 8 weeks to make antibodies against HIV, but HIV tests differ in how early they are able to detect antibodies. Although most HIV tests look for these antibodies, some look for the virus itself. The period after infection but before the test becomes positive is called the window period. See When should I get tested for HIV? to learn more about the window period.
If you receive a negative HIV test result within the “window period”, you need to have a follow-up test to confirm your results. You can also confirm when you need to be retested with a health professional.
If you receive a negative test after the window period, remember there are things you can do to stay negative. See How can I protect myself from HIV? for ways to prevent HIV.
What if I test positive for HIV?
If you had a rapid screening test, the testing site will arrange a follow-up test to make sure the screening test result was correct. If your blood was tested in a lab, the lab will conduct a follow-up test on the same sample. If the follow-up test is also positive, it means you are HIV-positive.
The sooner you take steps to protect your health, the better. Early treatment with antiretroviral drugs and a healthy lifestyle can help you stay well. Prompt medical care prevents the onset of AIDS and some life-threatening conditions.
Here are some important steps you can take right away to protect your health:
See a licensed health care provider, even if you don’t feel sick.
Your local health department can help you find a health care provider who has experience treating HIV. There are medicines to treat HIV infection and help you stay healthy. It’s never too early to start treatment. Current guidelines recommend treatment with antiretroviral therapy (ART) for all people with HIV, including those with early infection.
Get screened for other sexually transmitted infections (STIs). STIs can cause serious health problems, even when they don’t cause symptoms. Using a condom during all sexual contact (anal, vaginal, or oral) can help prevent many STIs.
Have a TB (tuberculosis) test. You may be infected with TB and not know it. Undetected TB can cause serious illness, but it can be successfully treated if caught early.
Get help if you smoke cigarettes, drink too much alcohol, or use illegal drugs (such as methamphetamine), which can weaken your immune system. Find substance abuse treatment facilities near you.
To avoid giving HIV to anyone else:
- Tell your partner or partners about your HIV status before you have any type of sexual contact with them (anal, vaginal, or oral).
- Use latex condoms and/or dental dams with every sexual contact. If either partner is allergic to latex, plastic (polyurethane) condoms for either the male or female can be used.
- Don’t share needles, syringes, or other drug paraphernalia with anyone.
- Stay on HIV treatment, or ART, to keep your virus under control and greatly reduce your ability to spread HIV to others.
- If your main partner is HIV-negative, discuss whether he or she should consider pre-exposure prophylaxis (PrEP)—medications to prevent HIV.
Can I get HIV from someone who is living with HIV but has undetectable viral load?
Yes. Even though having an undetectable viral load greatly lowers the chance that a person with HIV can transmit the virus to a partner, there is still some risk.
Viral load refers to the amount of HIV in the blood. An undetectable viral load is when the amount of HIV in the blood is so low that it can’t be measured. Antiretroviral therapy (ART) reduces viral load, ideally to an undetectable level, when taken consistently and correctly. A person with HIV can still potentially transmit HIV to a partner even if they have an undetectable viral load, because
- HIV may still be found in genital fluids (e.g., semen, vaginal fluids). The viral load test only measures virus in blood.
- A person&rquo;s viral load may go up between tests. When this happens, they may be more likely to transmit HIV to partners.
- Sexually transmitted diseases (STDs) increase viral load in genital fluids.