CD4 and infection: Consistent with the estimated decreases in median time to diagnosis, the probability of receiving an HIV test within 1 year after infection increased by 31 percentage points from 2000 to 2020 in sub-Saharan Africa, and the probability of receiving a test before reaching a CD4 count threshold lower than 350 cells per μL increased by 52 percentage points over the same period (table; figure 5).