CD4 Cell Count

CD4 cells are the immune system’s leaders, handing out orders to nearly every other cell. For people with HIV, CD4 counts are the No. 1 sign of immune strength.

CD4 counts above 350: Most people with HIV are not at higher risk of illness and likely needn’t start HIV treatment.

CD4s between 200 and 350: It’s time to think seriously about treatment. Consult with your doctor and weigh your options.

CD4s below 200: Very serious infections are much more likely at this level. If you haven’t already, talk to your doctor about starting HIV treatment and get preventive treatment against opportunistic infections.

Test Tip: Most experts suggest CD4 measurements every three to six months—more often if they’re lower or changing quickly. Low CD4 counts are a sign of HIV in need of treatment. HIV may cause other numbers (e.g. neutrophil counts) to fall as well, which may call for treatment. Talk to your doctor about your options.