An HIV viral load is a blood test that measures the amount of HIV in a sample of your blood. HIV stands for human immunodeficiency virus. The test looks for genetic material from the virus in your blood. These tests are called molecular tests or nucleic acid amplification tests (NAAT or NAT). There are several types of NAAT tests. A PCR test is one type of NAAT that may be used to find HIV.
HIV is a virus that destroys certain cells in your immune system. These cells protect your body against diseases from germs, such as viruses, bacteria, and fungi. If you lose too many immune cells, your body will have trouble fighting off infections and other diseases.
You can get HIV from contact with the blood of a person who has an HIV infection. This usually happens through sex or sharing needles or other equipment used to inject drugs.
HIV is the virus that causes AIDS (acquired immunodeficiency syndrome). AIDS is the final, most serious stage of an HIV infection. Without treatment, the amount of HIV in your body can increase. It can gradually destroy your immune system and become AIDS. With AIDS, your body has trouble fighting off infections from germs that usually don’t cause problems in healthy people. These are called opportunistic infections, and they can become life-threatening. AIDS increases your risk of developing certain cancers, too.
Most people with HIV don’t have AIDS. If you have HIV, you can take HIV medicines that protect your immune system and help prevent you from getting AIDS. Medicines that treat HIV are called antiretroviral therapy (ART). ART can’t get rid of HIV completely, so you’ll need to take medicines for the rest of your life. But ART can control HIV and help you live a longer, healthier life.
Having regular HIV viral load tests is an important part of making sure your HIV medicines are keeping your viral load low, so you stay healthy.
Other names: nucleic acid testing, NAT, nucleic acid amplification test, NAAT, HIV PCR, RNA Test, HIV quantification
What is it used for?
An HIV viral load test is mainly used after you’re diagnosed with HIV to:
- Guide decisions about your treatment
- Check how well your HIV medicines are working
- Watch for any changes in your HIV infection
HIV viral load testing is also used to test newborn babies when they are born to a person who has HIV. That’s because HIV can be passed to a baby during pregnancy, childbirth, and through breast milk.
In certain cases, an HIV viral load test may be used to diagnose HIV. Usually, HIV screening tests are used first. That’s because HIV viral load tests are expensive. But viral load tests can find HIV sooner after an infection than screening tests. So, your health care provider may order this test if your risk of having HIV is very high.
Why do I need an HIV viral load?
A viral load test is needed to guide treatment decisions. If you have HIV, you’ll probably start taking HIV medicines soon after your diagnosis. But first, you’ll need a viral load test to find out how much virus is in your blood. This information helps your provider choose the right medicines for you. Your first test result will be compared with later test results to see if the medicines are working.
A viral load test is needed to see how well treatment is working and to monitor your HIV infection. The goal of HIV treatment is to reduce the amount of virus in your blood until there’s too little to show up on a test. You’ll need to have regular viral load tests to see whether your viral load is dropping enough. HIV viral load tests are usually done:
- Before you start taking medicine
- About two to eight weeks after starting or changing HIV medicines
- Every three to six months to monitor your infection when your treatment is working well
Your provider may order an HIV viral load test to diagnose HIV if:
- You recently had a high-risk exposure to HIV. High-risk exposures include:
- Having vaginal or anal sex with someone who has HIV or whose HIV status you don’t know
- Sharing needles, syringes, or other items used to inject drugs with other people
- Exchanging sex for money or drugs
- Having a sexually transmitted disease (STD), such as syphilis
- Having sex with anyone who has done anything listed above
- Flu-like symptoms, such as fever, chills, aches
- Extreme fatigue
- Swollen lymph nodes (in your neck, groin, or armpit)
- Sores in your mouth
If you think you were exposed to HIV, talk with your provider right away about getting tested. You may also be able to have emergency treatment to prevent HIV infection within the first 3 days after a possible exposure.
What happens during an HIV viral load?
A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
Will I need to do anything to prepare for the test?
You don’t need any special preparations for an HIV viral load. But if you are getting this test to find out if you are infected with HIV, you should talk with a counselor before or after your test so you can better understand the results and your treatment options.
Are there any risks to the test?
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
What do the results mean?
If you have an HIV viral load test because you have HIV:
- A negative or undetectable viral load means that you have so little HIV in your blood that the test can’t find it. This means that your HIV medicines are working well to protect your immune system, and you are unlikely to spread HIV through sex. It does not mean you’re cured. You must continue to take your medicines as prescribed to keep your HIV in control.
- A low viral load means your medicine is stopping the virus from growing and your infection is unlikely to get worse.
- A high viral load means the virus is growing and your treatment is not working well. The higher the viral load, the more risk you have for infections and diseases related to a weak immune system. It may also mean you have a higher risk for developing AIDS. If your results show a high viral load, your provider will probably change your medicines.
If you had an HIV viral load test to diagnose whether you have HIV:
- A normal or negative result means that no HIV was found in your blood, and you are probably not infected with HIV.
- A result that shows any amount of virus in your blood means you have an HIV infection. Your provider will likely order other tests, including a CD4 count, to see how much HIV has damaged your immune system.
If you have questions about your results, talk with your provider.
Is there anything else I need to know about an HIV viral load?
If you are living with HIV, you will have regular viral load tests to monitor your infection and treatment. It’s best to have the same type of test done at the same lab if possible. That’s because labs have different ways of measuring HIV viral load. Your provider needs to compare your test results over time to see if your viral load is going up or down, and different tests from different labs can be difficult to compare.
Courtesy of MedlinePlus from the National Library of Medicine.