CD4 and infection: It has recently been shown that initiation of ART in HIV-1-infected patients during the early asymptomatic stage of infection, defined by a CD4+ T-cell count of more than 500 cells/μL, compared with patients who received ART when their CD4+ T-cell count decreased to 350 cells/μL, provided a net clinical benefit (Insight START Study group 2015).[1] This has been quantified through a cumulative clinical primary end point, gathering serious AIDS-related events together with non-AIDS-related events.