This Article Full Text Full Text (PDF) Other Versions of this Article: JCM.00305-08v1 46/6/1985    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Google Scholar Articles by Okabayashi, T. Articles by Fujii, N. PubMed PubMed Citation Articles by Okabayashi, T. Articles by Fujii, N.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, June 2008, p. 1985-1988, Vol. 46, No. 6
0095-1137/08/$08.00+0     doi:10.1128/JCM.00305-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Occurrence of Norovirus Infections Unrelated to Norovirus Outbreaks in an Asymptomatic Food Handler Population

Department of Microbiology, Sapporo Medical University School of Medicine, S1-W17, Chuou-ku, Sapporo, Hokkaido 060-8556, Japan,¹ Hokkaido Laboratory, SRL Co., Ltd., S19-W13, Chuou-ku, Sapporo, Hokkaido 064-0919, Japan,² Sapporo City Institute of Public Health, Kikusui 9-1, Shiroishi-ku, Sapporo, Hokkaido 003-8505, Japan³

Received 13 February 2008/ Returned for modification 8 April 2008/ Accepted 11 April 2008

Norovirus (NV) is the most common causative agent of nonbacterial gastroenteritis. Reports of surveillance of NV in facilities that reported outbreaks are frequently found in publications, but reports of that in facilities without outbreaks are not found. We investigated the molecular epidemiology of NV isolates derived from asymptomatic food handlers working at a nonoutbreak food catering facility in Hokkaido, Japan, from February to March in 2005 and January to February in 2006 by RNA polymerase gene sequencing. Approximately 12% (20/159) of the samples were positive for genogroup II (GII; 10.1% in 2005 and 14.2% in 2006). The GI genotypes were not detected. The data from the phylogenetic analysis indicated that, among the 20 strains detected, 13 strains were GII/genotype 2 (GII/2), two were GII/3, three were GII/8, and two were GII/12. GII/4, which has been found most frequently in recent outbreaks worldwide, including Japan, was not detected. We found that one individual was coinfected with two genotypes, GII/2 and GII/12. This is the first report of the detection of NV genotypes in asymptomatic food handlers working at a nonoutbreak facility. The excretion of NV from healthy individuals may be an infection source of NV outbreaks as well as other food-borne diseases.

Published ahead of print on 23 April 2008.