When the viral load goes up, your T cell count goes down.
One of the reasons that HIV (human immunodeficiency virus) is so dangerous is because it attacks the body’s own immune system. As the virus replicates, it attacks immune cells that help the body fight off illnesses. The result? Simple infections could become life threatening.
Luckily, today’s HIV medications can prevent and reduce this damage to the immune system. The medicine used to treat HIV is called antiretroviral therapy, or ART.
HIV Viral Load and the Immune System
The way that ART works is by preventing HIV from replicating in the body, which helps keep the viral load low. Viral load refers to the amount of virus in the bloodstream. ART targets HIV to keep the viral load low. Without treatment, the viral load will continue to increase and may begin to affect the immune system.
The reason HIV specifically affects the immune system is because the virus attacks immune cells. To be exact, it attacks CD4 T cells. These cells normally help your body fight off infection. When you don’t have enough of these cells, you could have a hard time fighting off simple infections. You will also be more at risk of contracting infections like tuberculosis or gonorrhea.
Measuring Viral Load and CD4 Count
Generally, you can’t “feel” HIV in your body, and you can’t “feel” your treatment working. For this reason, your doctor will use regular blood tests to check your viral load and CD4 count. Here’s what your doctor is looking for:
- Viral load: If your HIV medication is working, your viral load should stay fairly low. When viral load is low, you have a low risk of the disease progressing or transmitting the infection to others.
- CD4 count: The goal is to keep the CD4 count around “normal” levels, which is above 500. This means you have normal levels of CD4 T cells, so your immune system is able to protect you against infections. Your CD4 count may go up and down slightly over time, but it’s a concern if it starts going up significantly. A CD4 count below 200 is classified as AIDS (acquired immunodeficiency syndrome).
If your viral load stays low, and your CD4 count remains steady, that means your HIV treatment is working to keep your immune system working normally. Otherwise, it may be time to change your treatment regimen, or to make sure you’re not making any treatment mistakes. Luckily, there is a wide range of HIV medications today, so if one doesn’t work for you, there is likely another one that will.
Stella A. Safo, MD, is an HIV primary care physician and assistant professor of Medicine at the Icahn School of Medicine at Mount Sinai Hospital.