CONCISE COMMUNICATIONS Molecular Epidemiology of Childhood Astrovirus Infection

This study assessed the role of human astrovirus (HAstV) in outbreaks and sporadic cases of diarrhea among children attending child care centers (CCCs) and determined the infecting astrovirus antigenic types by reverse transcriptase±polymerase chain reaction (RT-PCR) and sequence analysis. Eight astrovirus outbreaks occurred in 6 CCCs. Of 179 children with diarrhea, 36 (20%) had astrovirus-associated diarrhea. Diarrhea stools obtained during di-arrhea outbreaks were more likely to contain astrovirus (40/476) than were samples not as-sociated with a diarrhea outbreak (14/452) (). Type-speci®c RT-PCR and DNA se-P!.001 quencing identi®ed 5 outbreaks associated with HAstV-1 and 3 outbreaks with HAstV-2. Sequential outbreaks in 2 CCCs occurred with a different type in the same year. Phylogenetic analysis identi®ed 6 clades of HAstV-1 and 2 clades of HAstV-2 during this 1-year surveillance. Astrovirus was a signi®cant cause of diarrhea outbreaks, and 2 antigenic types were present in the community during 1 diarrhea season. Human astroviruses (HAstVs) are nonenveloped, single-stranded RNA viruses that were ®rst identi®ed in 1975, by electron microscopy, in diarrhea stool specimens [1]. Astrovi