CD4 and AIDS: From our experience we were able to identify three categories of reasons for delays in treatment initiation: first, delays in confirming HIV infection and enrolment in the HIV/AIDS care program for HIV-exposed and infected children (A & B in Figure 3); second, delays in establishing the degree of HIV immunodeficiency using CD4 measurements (C in Figure 3); and third, delays in initiating ART after ART eligibility criteria (clinical and/or immunological) were met (D).