We describe the history of mother-to-child-prevention, time to HIV diagnosis and antiretroviral therapy of 55 hospitalized HIV-positive children (median age, 5.7 months). Of 31 (56%) mothers who knew their HIV status prior to pregnancy, 11 (35%) did not attend antenatal clinics; those who did attend had poor viral suppression. Despite rapid recognition and access to treatment, 13% of hospitalized HIV-positive infants died. Strategies to reach the mothers driving vertical transmission are imperative.