Occult Bacteremia and Fever Without Apparent Source in Infants and Young Children By Geoffrey A Weinberg, MD, Golisano Children's Hospital Reviewed / Revised Sep 2021 | Modified Sep 2022 View Patient Education Symptoms and Signs Diagnosis Treatment Key Points Topic Resources Evaluation and management... Occult bacteremia is the presence of bacteria in the bloodstream of febrile young children who have no apparent foci of infection and look well.