for Veterans and the Public

The weaker your immune system, the more likely you are to get an opportunistic infection.

In general, here's how a CD4 count relates to your risk of OIs:

Above 500 CD4 cells
No unusual infections likely to appear.

200-500 CD4 cells
There is an increased risk for certain infections, such as shingles, thrush, skin infections, bacterial sinus and lung infections, and TB.

<200 CD4 cells
There is an increased risk for PCP (pneumonia), and you should begin treatment to prevent it.

<100 CD4 cells
If counts are below 100, preventive treatment should begin for MAC and toxoplasmosis (if not already on PCP prophylaxis that helps prevent toxoplasmosis, like Septra)

<50 CD4 cells
Increased risk for cytomegalovirus