Previous studies on child mortality by maternal HIV status were conducted before the widespread scale–up of Option B+ (lifelong ART for all pregnant and breastfeeding mothers living with HIV infection regardless of CD4 cell count or clinical stage)¶¶ that occurred during 2011–2014 and the 2016 “treat-all” guidance for all persons living with HIV infection (5,6). Here, CD4 is linked to HIV infectious disease.