A newborn female infant is brought in for a 1-week follow-up visit with a pediatrician. She was born via cesarean section at 38 weeks gestation to a mother with HIV who had limited prenatal care and was not taking antiretroviral therapy. The mother received intravenous zidovudine just prior to the cesarean section. The infant is receiving a three-drug postexposure prophylaxis antiretroviral regimen for 6-weeks. The infant had a negative HIV nucleic acid test (NAT) at birth.