Overall, a higher CFR was observed in HIV-infected adults with CD4+ cell counts ≤100 cells per microliter (35.2%; [186/529]) than those with CD4+ cell counts >100 cells per microliter (15.5%; [63/406]) (adjusted IRR for disease syndrome 2.3 [95% CI: 1.7; 3.0]; p<0.0001). This evidence concerns the gene CD4 and Down syndrome.