A clustering outbreak of hand, foot, and mouth disease caused by Coxsackie virus A10.

A clustering outbreak of hand, foot, and mouth disease (HFMD) occurred from July, 1981 to January, 1982 in Matsue City and Gotsu City, Shimane Prefecture. Thirty-seven patients with clinical HFMD were virologically and serologically examined, and Coxsackie virus A10 (CA10) was isolated in 18 patients from vesicles (7/16), throat-swabs (9/31) and feces (6/7). During the period, no CA16 or enterovirus 71 were isolated from HFMD patients or from other diseases such as pharyngitis, febrile diseases, and aseptic meningitis. Serological diagnosis was performed employing an African green monkey kidney cell (AG-1)-adapted CA10 which demonstrated cytopathogenic effects on the cells. Paired sera from seven patients including three cases in which isolation failed showed a significant increase of neutralizing antibody titer against CA10. Finally, an etiological diagnosis was made in 21 out of 37 patients with clinical HFMD. This is the first report of a clustering outbreak of HFMD caused by CA10 in Japan.