HIV infection

HIV can be diagnosed through blood or saliva testing. Available tests include:

Antigen/antibody tests. These tests usually involve drawing blood from a vein. Antigens are substances on the HIV virus itself and are usually detectable — a positive test — in the blood within a few weeks after exposure to HIV.

Antibodies are produced by your immune system when it's exposed to HIV. It can take weeks to months for antibodies to become detectable. The combination antigen/antibody tests can take 2 to 6 weeks after exposure to become positive.

Antibody tests. These tests look for antibodies to HIV in blood or saliva. Most rapid HIV tests, including self-tests done at home, are antibody tests. Antibody tests can take 3 to 12 weeks after you're exposed to become positive.

Nucleic acid tests (NATs). These tests look for the actual virus in your blood (viral load). They also involve blood drawn from a vein. If you might have been exposed to HIV within the past few weeks, your health care provider may recommend NAT. NAT will be the first test to become positive after exposure to HIV.

Talk to your health care provider about which HIV test is right for you. If any of these tests are negative, you may still need a follow-up test weeks to months later to confirm the results.

Tests to stage disease and treatment

If you've been diagnosed with HIV, it's important to find a specialist trained in diagnosing and treating HIV to help you:

Determine whether you need additional testing

Determine which HIV antiretroviral therapy (ART) will be best for you

Monitor your progress and work with you to manage your health

If you receive a diagnosis of HIV/AIDS, several tests can help your health care provider determine the stage of your disease and the best treatment, including:

CD4 T cell count. CD4 T cells are white blood cells that are specifically targeted and destroyed by HIV. Even if you have no symptoms, HIV infection progresses to AIDS when your CD4 T cell count dips below 200.

Viral load (HIV RNA). This test measures the amount of virus in your blood. After starting HIV treatment, the goal is to have an undetectable viral load. This significantly reduces your chances of opportunistic infection and other HIV-related complications.

Drug resistance. Some strains of HIV are resistant to medications. This test helps your health care provider determine if your specific form of the virus has resistance and guides treatment decisions.

Currently, there's no cure for HIV/AIDS. Once you have the infection, your body can't get rid of it. However, there are many medications that can control HIV and prevent complications. These medications are called antiretroviral therapy (ART). Everyone diagnosed with HIV should be started on ART, regardless of their stage of infection or complications.

ART is usually a combination of two or more medications from several different drug classes. This approach has the best chance of lowering the amount of HIV in the blood. There are many ART options that combine multiple HIV medications into one pill, taken once daily.

Each class of drugs blocks the virus in different ways. Treatment involves combinations of drugs from different classes to:

Account for individual drug resistance (viral genotype)

Avoid creating new drug-resistant strains of HIV

Maximize suppression of virus in the blood

Two drugs from one class, plus a third drug from a second class, are typically used.

The classes of anti-HIV drugs include:

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) turn off a protein needed by HIV to make copies of itself.

Examples include efavirenz (Sustiva), rilpivirine (Edurant) and doravirine (Pifeltro).

Nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs) are faulty versions of the building blocks that HIV needs to make copies of itself.

Examples include abacavir (Ziagen), tenofovir disoproxil fumarate (Viread), emtricitabine (Emtriva), lamivudine (Epivir) and zidovudine (Retrovir).

Combination drugs also are available, such as emtricitabine/tenofovir disoproxil fumarate (Truvada) and emtricitabine/tenofovir alafenamide fumarate (Descovy).

Protease inhibitors (PIs) inactivate HIV protease, another protein that HIV needs to make copies of itself.

Examples include atazanavir (Reyataz), darunavir (Prezista) and lopinavir/ritonavir (Kaletra).

Integrase inhibitors work by disabling a protein called integrase, which HIV uses to insert its genetic material into CD4 T cells.

Examples include bictegravir sodium/emtricitabine/tenofovir alafenamide fumarate (Biktarvy), raltegravir (Isentress), dolutegravir (Tivicay) and cabotegravir (Vocabria).

Entry or fusion inhibitors block HIV's entry into CD4 T cells.