Isolation and charaterization of Vibrio cholerae O1 from stools of diarrheal patients and studies of the methods to determine the immunological responses

Abstract

Cholera continues to be one of the most common causes of morbidity and mortality among children and adults in developing countries like Bangladesh. The aim of the study was to determine the percentage of cholera patients among the all rice watery diarrhoeal patients by their different microbiological, biochemical and serological assays. Ten percent (n=10) patients were confirmed with Vibrio choleraeOl infected. Among Vibrio cholerae isolates, 7 patients were Ogawa and 3 were Inaba. Another aim was to evaluate the natural immune responses of native cholera patients infected by Vibrio cholerae 01. LPS specific IgA response showed an increase in convalescent sera at both day 7 and day 30 compared to the baseline, acute stage on day 2. The increase in both cases were statistically significant compared to baseline (P=0.0039). When sera were tested for LPS specific IgG responses, the response in the convalescent sera at day 7 were significantly higher than at the acute sera of day 2 (P=0.002). The day 30 IgG responses were also higher and statistically significant compared to that at day 2 (P=0.0039). CTB specific IgA response at convalescent stage at day 7 was significantly increased (P=0.002). CTB specific IgA response at day 30 compared to that of the acute stage at day 2, was statistically significantly increase (P=0.0059). When sera were tested for response to CTB specific IgG, the responses of both the convalescent sera at day 7 and day 30 were found an increase compared to the response at day 2. The responses were also statistically significant (P=0.002). The vibriocidal antibody response was significantly increased at the convalescent stage on day 7 (P=0.002), and at day 30 (P=0.002).