How Is HIV Diagnosed?

Table of Contents
View All
Table of Contents

Human immunodeficiency virus (HIV) is the virus that causes AIDS. While effective treatment is available to help people with HIV live long, healthy lives, in order to receive HIV treatment people first need to know that they are infected.

As early symptoms from HIV are often mild and go unnoticed, HIV testing is the only way to know for sure whether you are infected with the virus. HIV testing is widely available, often without cost.

The Centers for Disease Control and Prevention (CDC) runs a website on which people can find fast, free, and confidential HIV testing at gettested.cdc.gov. HIV testing is accessible across medical settings, and tests can even be purchased for home use at drugstores or on the Internet.

This article will discuss who should be tested for HIV, the types of tests available, how the results are interpreted, what comes next if your HIV test result is positive, and how to cope with an HIV diagnosis.

How to Cope With an HIV Diagnosis

Verywell / Theresa Chiechi

Who Should Be Tested for HIV?

The CDC recommends that everyone between the ages of 13 and 64 get tested for HIV at least once as part of their routine healthcare regimen. However, people who are at increased risk for HIV should be tested at least once a year, if not more often. These risk factors include:

  • Being a man who has sex with men
  • Having vaginal or anal sex with an HIV-positive partner
  • Having had more than one sexual partner since your last HIV test
  • Injecting drugs
  • Sharing needles or other drug paraphernalia
  • Exchanging sex for drugs or money
  • Having been diagnosed with another sexually transmitted infection (STI)
  • Being diagnosed with hepatitis or tuberculosis
  • Having sex with anyone who has one of the above risk factors

Pregnant people also should be tested for HIV at least once during pregnancy. This is because HIV treatment during pregnancy is a highly effective way of preventing transmission to the infant.

Knowledge Is Power

Without HIV testing, it's possible to be infected with HIV for years without recognizing that you have the virus and are putting other people at risk. Researchers estimate that as many as four out of 10 people newly infected with HIV got the virus from someone who didn't know they were HIV positive.

Practicing safer sex, using PrEP, (preexposure prophylaxis), avoiding infected needles, and engaging in other preventive behaviors are highly effective at avoiding HIV infection. However, they need to be practiced consistently. People who don't know or think they are at risk of exposure may not do what they need to in order to stay safe.

How HIV Is Diagnosed

There are three basic types of HIV test:

  • Antibody tests
  • Antigen/antibody tests
  • Nucleic acid tests (NATs)

Antibody Tests

Antibody tests were the first HIV tests available. These tests look for your body's immune response to HIV infection in the form of antibodies. Most rapid tests are antibody tests. Antibody tests require either blood draws, finger sticks, or saliva samples.

Antibody tests may detect the infection response 23–90 days after exposure. Those done with blood drawn from a vein can detect HIV antibodies sooner.

Antigen/Antibody Tests

Antigen/antibody tests look for both the body's response to HIV infection and proteins created by the virus. These proteins are known as antigens, and they are part of what stimulates the immune response. These tests are done on blood from a vein or a finger prick.

Depending on the specific type of test, antigen/antibody tests may be able to detect infections as early as 18 days after exposure, but they may not be accurate until up to three months afterward.

Nucleic Acid Tests

Nucleic acid tests look directly for the presence of the virus in the blood. These tests can also determine how much HIV is in the blood.

This type of test is not often used for screening except for people who have recently been exposed to the virus. These tests are expensive and not as easily adapted to rapid testing in clinics. They detect HIV infection sooner than antibody tests (10–33 days after exposure).

Waiting for Results

How fast you receive your HIV test results depends on where you get tested and the type of test that is used. Rapid tests can give results in as little as 20–30 minutes. This includes some self-administered tests. Tests that need to be sent out to a lab may return results for anywhere from a few days to a week.

What HIV Test Results Mean

A negative result on an HIV test means that no infection was detected. However, accuracy depends on when you were last potentially exposed to HIV and the type of test you take. Antibody tests in particular may not be accurate until at least three months after exposure.

The time during which an HIV test result is not accurate is known as the window period. The window period varies depending on the type of HIV test and type of sample used (finger stick, blood from a vein, or saliva).

When to Be Tested Again

If you have a negative test within the window period from your last potential exposure, you should be tested again after the window period has passed.

A positive result on an HIV test means that either HIV has been detected in your body or your body seems to be responding to an HIV infection. Depending on the type of test used, a positive result may be preliminary. Preliminary results require additional testing before it can be determined if you actually are infected with HIV.

Rapid test results are generally preliminary. HIV tests that are sent to a lab and initially come back positive may be confirmed by running an additional test before results are reported to you.

A positive HIV test result does not mean that you are immunocompromised. Understanding how and whether HIV has affected your overall health requires additional testing.

What Happens After a Positive HIV Diagnosis

If you have recently been diagnosed with HIV, you will likely be referred to a specialist for further testing and care. People who are looking for additional provider options for HIV care can find a national directory run by the CDC at findhivcare.hrsa.gov. Some primary care providers also offer HIV treatment.

After an HIV diagnosis, your doctor will likely perform several types of tests to see how and if HIV has affected your health. These tests include:

  • Viral load: This test shows how much of the virus is in your blood.
  • CD4 count: This test determines the health of your immune system. People with a CD4 count of less than 200 are considered to have advanced HIV infection. People with a CD4 count of 200–500 are considered immunosuppressed.

Any person confirmed to have HIV should be started on antiretroviral therapy as soon as possible to improve their outcome. These tests can also be used to determine whether any antiretroviral therapies are working and to monitor the progression of your HIV.

The goal of antiretroviral therapy is to help you reach an undetectable viral load, in which there is so little HIV in your blood that it cannot be detected on a nucleic acid test. People with an undetectable viral load cannot transmit the virus to others.

Coping with a Positive HIV Diagnosis

Being diagnosed with HIV can be scary and overwhelming, even when people know that effective treatment is available. However, there are several things that can help you cope with a new HIV diagnosis, including the following:

  • Seek out reliable information about HIV. Accurate information about the virus can help you make better decisions about treatment and feel better about your prognosis.
  • Find a doctor with whom you feel comfortable. This can make a big difference in your willingness to follow up with care. It can also help you feel more in control.
  • Talk to other people in similar circumstances. Joining support groups for people with HIV can make you feel less alone.
  • Consider speaking with a therapist. Being diagnosed with HIV can cause depression, anxiety, and similar conditions. Finding a good therapist can help you cope.

Most importantly, remember that people can live long, healthy lives with HIV. Your new diagnosis doesn't need to be the determining factor in your life.

Summary

HIV is diagnosed through testing. Everyone should be tested at least once, and those who are at higher risk should be tested more often. Different types of tests can detect HIV at different points in the infection.

If HIV is detected, you are diagnosed as having HIV. You can expect more testing and also starting on antiviral medications. You may need help to cope with getting an HIV diagnosis.

A Word From Verywell

Getting tested for HIV is a good way to take care of yourself. Although it can be scary to get an HIV test, the fact that effective treatment exists means that it really is better to know. Early treatment can make a big difference in how HIV affects your health long term.

Getting tested for HIV is also a good way to be considerate of your sexual partners. People who know they are HIV positive may be more likely to take precautions against transmitting the virus to others. They can also get treatment—and effective treatment is itself a form of prevention.

Was this page helpful?
5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. HIV testing. Updated June 9, 2020.

  2. US Preventive Services Task Force, Owens DK, Davidson KW, Krist AH, et. al. Screening for HIV infection: US Preventive Services Task Force recommendation statement. JAMA. 2019 Jun 18;321(23):2326-2336. doi:10.1001/jama.2019.6587

  3. Li Z, Purcell DW, Sansom SL, Hayes D, Hall HI. Vital signs: HIV transmission along the continuum of care — United States, 2016. MMWR Morb Mortal Wkly Rep. 2019;68:267–272. doi:10.15585/mmwr.mm6811e1

  4. Rodger A., Cambiano V, Bruun T, et al. Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): final results of a multicentre, prospective, observational study. Lancet. 2019 May 2; pii: S0140-6736(19)30418-0. doi:10.1016/S0140-6736(19)30418-0.

  5. Murphy RD, Gorbach PM, Weiss RE, Hucks-Ortiz C, Shoptaw SJ. Seroadaptation in a sample of very poor Los Angeles area men who have sex with men. AIDS Behav. 2013;17(5):1862-1872. doi:10.1007/s10461-012-0213-2