Tests to Monitor Your Health

It's likely that your healthcare provider will regularly test your blood to understand how effectively your body is fighting HIV. The information below describes the most common HIV tests.

Common HIV Tests: How Often and What Do They Mean?

Viral Load: This is the most important indicator of how well your treatment regimen is working. The viral load (or amount of HIV in your blood) should decrease or stabilize if your medications are effective. Your viral load should be tested 2 to 8 weeks after you start treatment, or if you make a change to your treatment, then every 3 to 4 months throughout treatment to make sure your drugs are still working. A goal of HIV treatment is to reduce viral load to undetectable.*

CD4+ cell count: This test measures the amount of CD4+ cells in your blood. This number should remain stable or go up if your drugs are working. Your CD4+ count should be tested every 3 to 6 months throughout your treatment. HIV treatment should increase your CD4+ count or at least keep it from going down. The U.S. Department of Health and Human Services recommends beginning treatment before the CD4+ cell count falls below 350 cells/mm³. Some clinicians may consider treatment in patients with CD4+ count above 350 cells/mm³.

HIV Drug Resistance: It is possible to be infected with a strain of HIV that is already resistant to some forms of HIV therapy. A resistance test assesses if an individual's strain of HIV is already resistant to certain medications. The U.S. Department of Health and Human Services recommends performing a drug resistance test in all patients who have never used HIV medication.

Other Tests: Your healthcare provider will also recommend other tests to evaluate your overall health or determine if you are infected with other diseases. These tests may include a complete blood count, urinalysis, tuberculin skin test (unless a history of prior tuberculosis or positive skin test), hepatitis A, B, and C blood exam, and PAP smear in women. Tests of your blood sugar and cholesterol may also be performed if you are at risk for cardiovascular disease or to see how healthy you are before starting HIV therapy.

When to Change Treatment

If your test results indicate your treatment regimen is no longer working the way it should - meaning that the drugs are not suppressing your viral load and improving/maintaining your CD4+ cell count - you and your healthcare provider might consider switching your HIV treatment. Talk to your healthcare provider if side effects are preventing you from taking your medication.

* "Undetectable" is defined as a viral load that is too low to be picked up by a particular test. Typically, it is a viral load of less than 400 or 50 copies/mL (depending on test used).