Infections affecting infants in the hospital nursery are generally divided into those with a prenatal onset and early- and late-onset postnatal infections. Little attempt has been made to differentiate infections affecting infants more than a week of age from those with an onset at several months of age. Three cases are presented which demonstrate how, currently, infants far older than one month of age are being treated for nosocomial, nursery-associated infections. This information has implications both for treatment decisions and for the gathering of epidemiologic data on nosocomial infections.