HIV Viral Load

Does this test have other names?

Viral load test, HIV-RNA tests

What is this test?

This is a blood test to measure the amount of HIV in your blood. HIV causes AIDS. This test should be done 2 to 8 weeks after you're diagnosed with HIV and then every 3 to 4 months during long-term therapy. If your treatment is effective, your viral load should go down in 4 to 6 months.

Although HIV antibody testing is widely used to find HIV, viral load testing can also diagnose the infection. Because the viral load test measures genes and chemical compounds found in HIV, it can find the virus in your blood within days of infection.

HIV antibody testing, however, may give a negative result until the virus has been in your body for 2 to 6 months. You may not show signs of HIV even if the virus is already multiplying in your blood. Because HIV has no cure, it's important to find out as soon as possible if you have the virus so treatment can be started.

If you're taking medicines to lower levels of the virus in your body, this test shows if the medicines are working. The more your viral load goes down, the healthier you are likely to be. 

Why do you need this test?

You may need this test if you've had unprotected sex or shared contaminated needles and want to know whether you've contracted HIV. Standard antibody tests aren't as accurate as the viral load test because they can take up to 6 months to show that you have HIV. In that time, it's possible to infect someone else.

If you're pregnant, it's especially important to find out if you have HIV. Starting treatment right away can lower the risk of passing the virus on to your baby.

It's also likely that you will have this test if you've already been diagnosed with HIV. You may have the first test 2 to 8 weeks after diagnosis and again at 4- to 6-month intervals. The findings help health care providers find the best medicine to get your viral load down and keep you healthy. 

What other tests might you have along with this test?

You may also have a CD4 test, which measures the strength of your immune system.

What do your test results mean?

Test results may vary depending on your age, gender, health history, and other things. Your test results may be different depending on the lab used. They may not mean you have a problem. Ask your health care provider what your test results mean for you.

Your test result is a number that shows how many copies of HIV exist in 1 milliliter of your blood. A normal count is a virus level so low it can't be found.

Low counts mean the virus is not highly active and your treatment is working. The higher the number, the more likely you are to become ill or show signs of immunity problems linked to AIDS.

How is this test done?

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

Does this test pose any risks?

Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore. 

What might affect your test results?

The results can be skewed if you've recently had a vaccine, such as a flu shot, or if you have an active infection. Experts advise that you not have this test within 4 weeks of an infection or vaccine.

How do you get ready for this test?

You don't need to prepare for this test. If you're having this test to find out your HIV status, make sure you get counseling before or after the test. Tell your health care provider about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illegal drugs you may use.