What Does HIV Viral Load Mean?

What is a viral load?

Everyone diagnosed with HIV needs to know their viral load. An HIV viral load is the amount of HIV in a drop of blood. When it comes to treatment, the goal is to lower your viral load, or reduce the amount of HIV in your blood.

HIV affects your immune system and attacks the CD4 cells (T-cells), a type of white blood cell. Your CD4 count provides a rough guide of how healthy your immune system is. A high viral load can cause a low CD4 cell count. This makes it harder for your body to fight infection and increases your risk for illness. Untreated HIV can cause long-term complications and develop into AIDS.

There isn't a “normal” viral load per se. Your doctor will look at your viral load and CD4 count to see how well your treatment is working. These numbers also tell your healthcare team how HIV is affecting your body. The ideal results are to have a very low or undetectable viral load and high CD4 count. Read on to learn more about HIV viral load and what the numbers mean.


Viral load test

How do you test for your viral load?

When you’ve been diagnosed with HIV, your doctor monitors your viral load over several months to determine your individual set point, which is your stabilized viral load after the primary infection. Your doctor uses this number to assess whether HIV treatment is effective.

Viral load testing is the lab test that shows how much HIV is in 1 milliliter of blood. In addition to a viral load test, your doctor runs testing to learn your CD4 cell count.

How your CD4 count and viral load affect treatment

Your CD4 count is what your doctor looks at when recommending treatment.

CD4 count Meaning, or recommendation
between 500 and 1,200, or above 29 percent no HIV treatment, if not infected
above 350 no HIV treatment, if not infected
below 350 start or continue HIV treatment
below 200, or below 14 percent start or continue HIV treatment

People who don't have HIV usually have a CD4 cell count between 500 and 1,200. Your risk of developing an illness or infection from HIV is higher when your CD4 count is below 200. To raise your CD4 count and lower your viral load, you have to take your medication regularly and as instructed.

Sometimes taking other prescription and over-the-counter medications, recreational drugs, and herbal supplements interfere with the effectiveness of HIV treatment.

Your doctor may adjust your treatment regimen to make it more effective. Some people develop a resistance to HIV medications. Your doctor can test your blood to check the amount of HIV medication in your system.


What the numbers mean about transmission

The higher your viral load, the higher the risk of passing HIV to a partner through sex, or to a baby through breast-feeding. If you're pregnant and HIV-positive, taking antiretroviral therapy during pregnancy and labor reduces the risk of your baby being born with HIV. Babies born to HIV-positive mothers receive HIV medicine for six weeks after birth and are tested for the virus over the first six months of life. Avoid breast-feeding your baby if you have HIV.

Viral load Results
between 100,000 and 1 million high
below 10,000 low for people with HIV who are not on treatment
below 50 undetectable

There’s no cure for HIV, so there's always a chance of your viral load going back up if you stop taking your medication. If your viral load is detectable, you can pass the virus to others through bodily fluids such as semen and breast milk. The risk decreases when your viral load is lower.

An undetectable viral load doesn't mean you're cured. Transmitting the virus is still possible, but the risk is much lower. The CDC continues to recommend sticking with treatment to stay virally suppressed, improve your overall health, and reduce your risk of transmitting the disease to your partner.

Increased viral load

It’s best to look at your viral load over time, rather than comparing one test to another. An increase shouldn’t worry you unless it’s continuously increasing or has increased more than threefold. Sometimes infections and vaccinations, like a flu shot, can cause a temporary increase in your viral load. There are a number of reasons your viral load might go from undetectable to low on consecutive tests. Talk to your doctor about possible causes. It doesn’t necessarily mean your treatment isn’t working.


Test frequency

How often should you test your viral load?

The frequency of viral load testing varies. It depends on whether you’re newly diagnosed with HIV and whether you're showing symptoms. You’ll have a viral load test before beginning treatment. Then you’ll typically have periodic testing every three to six months if you’re recently infected or diagnosed.

Initial testing

Your viral load should fall when you start your treatment. In most cases, you’ll repeat viral load testing about one month after starting treatment, and then three months after that. If your viral load decreases with each test, this indicates that your treatment is working.

Three to six months in

Within three to six months of beginning treatment, your HIV viral load should reach an undetectable level. If your viral load increases or doesn’t reach an undetectable level, your doctor will discuss possible reasons with you.

Long-term testing

You’ll repeat testing every six months if your viral load is undetectable. If your viral load is detectable again during a follow-up test, your doctor will adjust your treatment, if necessary. Sometimes an infection like the common cold or flu can cause a temporary increase in your viral load.

Safe sex

Safe sex: What to do

A viral load only indicates HIV in your blood, but HIV may still be found in genital fluids like semen and vaginal fluids. Your viral load can also go up and down between tests, which are generally every six months. In between testing, sexually transmitted infections can increase your viral load. This makes transmission of the virus still possible.

Lowering transmission risks

If you are HIV-positive, take your antiretroviral therapy regularly and as directed. Your risk of passing the infection to a partner decreases with a lower viral load. Using condoms and engaging in sexual activities that don’t involve exchange of bodily fluids can also lower your risk of transmission.

It’s still important to practice safe sex, if you are HIV-positive. You may want to encourage your partner to talk to their doctor about pre-exposure prophylaxis or PrEP. This medication is designed for HIV-negative people who are at high risk for HIV. When taken as prescribed, it decreases their risk of infection through sex by more than 90 percent.

If you or your partner suspect that you’ve been exposed to the virus, talk to your doctor about post-exposure prophylaxis (PEP). This medication reduces the risk of infection when taken within three days of possible exposure, and for up to four weeks. HIV-negative partners should get tested for the virus at least once a year.



Sex and undetectable viral load

  • Some sources say that the chances of transmitting HIV with an undetectable viral load is zero. Is this true?
  • While some experts have gone on record indicating that your chances of contracting HIV from someone who is on ‘durable’ antiretroviral therapy (ART) are zero, the authors of the quoted study didn’t conclude that transmission risk was zero nor did they advocate unprotected sex among these couples. The authors of the study noted that eight partners became infected.

    The CDC also still doesn’t endorse this position and continues to caution that ‘a person with HIV can still potentially transmit HIV to a partner, even if they have an undetectable viral load.’

    - Timothy J. Legg, PhD, CRNP
  • Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

More about this study: Experts who have gone on record quote a study published in the New England Journal of Medicine in September 2016 about HIV-1 transmission. The study concluded that early initiation of antiretroviral therapy “led to a sustained decrease in genetically linked HIV-1 infection in sexual partners.” But it doesn’t eliminate all cases of transmission in couples where one is HIV-positive.

The authors of the study also noted that eight members of the discordant couples became infected. They speculated that “four of these infections probably occurred before the infection was virally suppressed in the index participant,” but this is not certain. In the case of the other four infections, they noted that the “partner infection occurred after ART failed in the index participant.”




An HIV diagnosis can be life-changing, but it’s still possible to be healthy and active. Early diagnosis and treatment can reduce your viral load and chances of illness. Bring any concerns or new symptoms to your doctor’s attention. Take steps to live a healthy life, such as:

  • getting regular checkups
  • taking your medication
  • exercising regularly
  • eating a healthy diet

You can also talk to a trusted friend or relative for emotional support, or ask your doctor about HIV/AIDS support groups. There are many local support groups available for you and your loved ones. You can find the hotlines for HIV and AIDS groups by state at

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