Outbreak of acute gastroenteritis associated with group A rotavirus and genogroup I sapovirus among adults in a mental health care facility in Japan

Abstract

An outbreak of acute gastroenteritis consisting of 57 cases occurred in a mental health care facility in Takasaki city, Japan during 6th February and 27th March 2002. A total of 18 fecal specimens collected from 17 residents and one member of the medical staff during this outbreak were tested for the presence of viral enteropathogens by RT‐PCR and latex agglutination. Group A rotavirus and sapovirus were detected in 5 out of 18 fecal specimens (55.6%). To our knowledge, this is the first finding of an outbreak of gastroenteritis associated with co‐circulation of different kinds of viruses such as group A rotavirus and sapovirus. All of group A rotaviruses were typed further as P[4]G2 strains. Both rotavirus and sapovirus were subjected to molecular analysis by sequencing. It was noteworthy that all rotaviruses and sapoviruses had high homologies, respectively, to each other and sapoviruses presented a potential novel sapovirus genogroup I (GI) genotype, which was obviously different from any GI genotypes (GI‐a, b, c, and d). The outbreak associated with these viruses spread gradually from dormitory to dormitory, suggesting a spread by person‐to‐person contact, although investigation on the route of transmission of the outbreak is lacking. The findings confirm the presence of group A rotavirus and sapovirus are important in acute gastroenteritis among adults in Japan. J. Med. Virol. 75:475–481, 2005.