The amount of CD4 cells, a subset of white blood cells, provides an indication of the health of the immune system, and as such, CD4 cell count testing is a vital tool that can be used to help decrease the number of people dying from HIV/AIDS.

In its latest guidelines for managing advanced HIV disease, or AHD, the World Health Organization notes, “CD4 cell count testing at baseline for all people living with HIV remains important,” adding that “relying on clinical staging alone risks missing substantial numbers of people living with HIV with severe immune suppression.”

CD4 cell count tests are also useful to help diagnose patients who may have health systems compromised by opportunistic infections related to AHD, such as cryptococcal disease and tuberculosis, and — according to WHO — can foster a “shift away from symptom-based tuberculosis screening toward an approach of testing all those at high risk of disease.”

In a recent Devex survey, health care professionals agreed that CD4 cell count testing — which is recommended in the WHO “package of care” — is necessary, citing insufficient CD4 testing as one of the reasons for the entrenchment of AHD in low- and lower-middle-income countries.

The survey, conducted from Nov. 16 to Dec. 11, 2020, interviewed more than 700 global health professionals based in 90 countries. The objective was to identify barriers and opportunities around the use of CD4 cell count testing as part of the efforts to reduce AIDS-related deaths.