Severe Parechovirus Infection in Norwegian Infants

Background: Human parechovirus genotype 3 (HPeV-3) has been linked to meningoencephalitis and sepsis-like disease in infants younger than 3 months. Methods: We present clinical and phylogenetic characteristics of 15 infants who were admitted with HPeV-3 infections to 3 hospitals in Norway during a period of 7 months in 2011. Results: Eleven patients had a sepsis-like disease, and meningoencephalitis was found in 10. Phylogenetic analyses of the viral protein (VP) 3/VP1 region showed that all HPeV-3 isolates clustered closely and differentially from previously known HPeV-3 lineages. Fourteen of the 15 infants recovered after 1-3 weeks. One boy had widespread cerebral magnetic resonance imaging abnormalities, but at 1 year of age he had a normal psychomotor status. Conclusion: A new HPeV-3-strain caused sepsis-like disease and meningoencephalitis in 15 Norwegian infants. All but 1 recovered within a few weeks.