Late-onset neonatal infections caused by group B Streptococcus associated with viral infection.

An association between viral infection and late-onset disease caused by group B Streptococcus (GBS), was systematically looked for in neonates hospitalized for fever during a 3 1/2 year period. Five neonates between 5 to 12.5 months of age presented with meningitis (2 cases) or with septicemia (3 cases) caused by GBS. Viral culture, immunofluorescence, and assay of IFNalpha in blood and cerebrospinal fluid were performed. A viral infection was proved in 4 cases and suspected in 1 case (rash and pharyngitis). We speculate that viral infection may provoke late-onset disease in colonized infants with GBS.