[The importance of circulating vibriocidal antibodies in a pos-epidemic region of diarrhea, São Bento do Una, State of Pernambuco].

The levels of vibriocidal antibodies were investigated among 41 adults without any past or present history of diarrhea due to Vibrio cholerae O1 who were living in the municipality of São Bento do Una, Pernambuco. A diarrhea outbreak occurred in this locality at the beginning of 2004, involving multiple bacterial agents, including Vibrio cholerae. The microtitration test was used to investigate the presence of anti-Ogawa and anti-Inaba vibriocidal serum antibodies. Vibriocidal titers e" 1:640 were considered indicative of infection by Vibrio cholerae O1. The frequency of the reagents was 36 (87.8%) for the Ogawa serovar, which showed that Vibrio cholerae O1 was possibly circulating during and/or after the diarrhea epidemic.