Last updated 9/13/2016; last reviewed 9/9/2016
- Without treatment, HIV infection advances in stages, getting worse over time.
- The three stages of HIV infection are (1) acute HIV infection, (2) chronic HIV infection, and (3) acquired immunodeficiency syndrome (AIDS).
- HIV can be transmitted (spread to others) during any stage of infection, but the risk is greatest during acute HIV infection.
- There is no cure for HIV infection, but HIV medicines (called antiretrovirals or ARVs) can prevent HIV from advancing to AIDS. HIV medicines help people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission.
There is no cure for HIV infection, but HIV medicines (called antiretrovirals or ARVs) can prevent HIV from advancing to AIDS. HIV medicines help people with HIV live longer, healthier lives. HIV medicines also reduce the risk of HIV transmission (the spread of HIV to others).
There are three stages of HIV infection:
- Acute HIV Infection
Acute HIV infection is the earliest stage of HIV infection, and it generally develops within 2 to 4 weeks after a person is infected with HIV. During this time, some people have flu-like symptoms, such as fever, headache, and rash. In the acute stage of infection, HIV multiplies rapidly and spreads throughout the body. The virus attacks and destroys the infection-fighting CD4 cells of the immune system. HIV can be transmitted during any stage of infection, but the risk is greatest during acute HIV infection.
- Chronic HIV Infection
The second stage of HIV infection is chronic HIV infection (also called asymptomatic HIV infection or clinical latency). During this stage of the disease, HIV continues to multiply in the body but at very low levels. People with chronic HIV infection may not have any HIV-related symptoms, but they can still spread HIV to others. Without treatment with HIV medicines, chronic HIV infection usually advances to AIDS in 10 years or longer, though it may take less time for some people.
AIDS is the final stage of HIV infection. Because HIV has severely damaged the immune system, the body can’t fight off opportunistic infections. (Opportunistic infections are infections and infection-related cancers that occur more frequently or are more severe in people with weakened immune systems than in people with healthy immune systems.) People with HIV are diagnosed with AIDS when they have a CD4 count of less than 200 cells/mm3, they have one or more opportunistic infections, or both. Without treatment, people with AIDS typically survive about 3 years.
This fact sheet is based on information from the following sources:
- HIV testing shows whether a person is infected with HIV. HIV stands for human immunodeficiency virus. HIV is the virus that causes AIDS (acquired immunodeficiency syndrome). AIDS is the most advanced stage of HIV infection.
- The Centers for Disease Control and Prevention (CDC) recommends that everyone 13 to 64 years old get tested for HIV at least once and that people at high risk of infection get tested more often.
- Risk factors for HIV infection include having unprotected sex (sex without a condom) with someone who is HIV-positive or whose HIV status you don’t know; having sex with many partners; and injecting drugs and sharing needles, syringes, or other drug equipment with others.
- CDC recommends that all pregnant women get tested for HIV as early as possible during each pregnancy.
What is HIV testing?
HIV testing shows whether a person is infected with HIV. HIV stands for human immunodeficiency virus. HIV is the virus that causes AIDS (acquired immunodeficiency syndrome). AIDS is the most advanced stage of HIV infection.
HIV testing can detect HIV infection, but it can’t tell how long a person has been infected with HIV or if the person has AIDS.
Why is HIV testing important?
Knowing your HIV status can help keep you—and others—safe.
If you are HIV-negative:
Testing shows that you don’t have HIV. Continue taking steps to avoid getting HIV, such as using condoms during sex and taking medicines to prevent HIV if you are at high risk of becoming infected with HIV (pre-exposure prophylaxis or PrEP). For more information, read the AIDSinfo fact sheet on HIV prevention.
If you are HIV-positive:
Testing shows that you are infected with HIV, but you can still take steps to protect your health. Begin by talking to your health care provider about antiretroviral therapy (ART). ART is the use of HIV medicines to treat HIV infection. People on ART take a combination of HIV medicines every day. ART helps people with HIV live longer, healthier lives. ART also reduces the risk of transmission of HIV. People infected with HIV should start ART as soon as possible. Your health care provider will help you decide what HIV medicines to take.
Who should get tested for HIV?
The Centers for Disease Control and Prevention (CDC) recommends that everyone 13 to 64 years old get tested for HIV at least once. As a general rule, people at high risk for HIV infection should get tested each year. Sexually active gay and bisexual men may benefit from getting tested more often, such as every 3 to 6 months.
Factors that increase the risk of HIV infection include:
- Having vaginal or anal sex without using a condom with someone who is HIV-positive or whose HIV status you don’t know
- Injecting drugs and sharing needles, syringes, or other drug equipment with others
- Exchanging sex for money or drugs
- Having a sexually transmitted disease (STD), such as syphilis
- Having hepatitis or tuberculosis (TB)
- Having sex with anyone who has any of the HIV risk factors listed above
Talk to your health care provider about your risk of HIV infection and how often you should get tested for HIV.
Should pregnant women get tested for HIV?
CDC recommends that all pregnant women get tested for HIV as early as possible during each pregnancy. Women who are planning to get pregnant should also get tested.
Women with HIV take HIV medicines during pregnancy and childbirth to reduce the risk of mother-to-child transmission of HIV. HIV medicines used as recommended during pregnancy can reduce the risk of mother-to-child transmission of HIV to less than 1%. For more information, read the AIDSinfo fact sheet on Preventing Mother-to-Child Transmission of HIV.
What are the types of HIV tests?
There are three main types of HIV tests: antibody tests, combination tests (antibody/antigen tests), and nucleic acid tests (NATs). How soon each test can detect HIV infection differs because each test has a different window period. The window period is the time between when a person gets HIV and when a test can accurately detect HIV infection.
- Antibody tests check for HIV antibodies in blood or fluids from the mouth. HIV antibodies are disease-fighting proteins that the body produces in response to HIV infection. It can take 3 to 12 weeks for a person’s body to make enough antibodies for an antibody test to detect HIV infection. (In other words, the window period for antibody tests in most people is somewhere between 3 to 12 weeks from the time of infection.)
- Combination tests (antibody/antigen tests) can detect both HIV antibodies and HIV antigens (a part of the virus) in blood. A combination test can detect HIV infection before an HIV antibody test. It can take 2 to 6 weeks for a person’s body to make enough antigens and antibodies for a combination test to detect HIV infection. Combination tests are now recommended for HIV testing that’s done in labs, and they are becoming more common in the United States.
- NATs look for HIV in the blood. NATs can detect HIV infection about 7 to 28 days after a person has been infected with HIV. NATs are very expensive and not routinely used for HIV screening unless the person had a high-risk exposure or a possible exposure with early symptoms of HIV infection.
A person’s initial HIV test will be either an antibody test or a combination test. If the initial test result is positive for HIV infection, then follow-up testing will be done to make sure that the diagnosis is correct. If the initial test result is negative and the test was done during the window period, re-testing should be done 3 months after the possible exposure to HIV.
How long does it take to get the results of an HIV test?
It usually takes a few days to a few weeks to get results of an HIV test. Some rapid HIV tests can produce results within 30 minutes.
Is there an HIV test for home use?
There are two HIV tests approved by the U.S. Food and Drug Administration (FDA) for home use. Both are HIV antibody tests.
The Home Access HIV-1 Test System is a home collection kit, which involves pricking the finger for a blood sample, sending the sample to a lab for testing, and then calling the lab for results as early as the next business day. If the result is positive for HIV, the lab will do a follow-up test on the same blood sample to confirm the initial HIV-positive test result.
The OraQuick In-Home HIV Test comes with a test stick and a tube with a testing solution. The test stick is used to swab the gums to get a sample of oral fluids. To get results, the test stick is inserted into the test tube. Test results are ready in 20 minutes. A positive result on this home HIV test must always be confirmed by additional HIV testing performed in a health care setting.
Is HIV testing confidential?
HIV testing can be confidential or anonymous.
Confidential testing means that your HIV test results will include your name and other identifying information, but only people allowed to see your medical records will see your test results. HIV-positive test results may be reported to local or state health departments to be counted in statistical reports. Health departments remove all personal information (including names and addresses) from HIV test results before sharing the information with CDC. CDC uses this information for reporting purposes and does not share this information with any other organizations.
Anonymous testing means you don’t have to give your name when you take an HIV test. When you take the test, you receive a number. To get your HIV test results, you give the number instead of your name.
Where can I get tested for HIV?
Your health care provider can give you an HIV test. HIV testing is also available at many hospitals, medical clinics, community health centers, and AIDS service organizations. Use this CDC testing locator to find an HIV testing location near you.
You can also buy a home testing kit at a pharmacy or online.