Affililations: *National Institute of Health, Department of Medical Sciences
Source: Bulletin of Department of Medical Sciences 1997; 39(4): 271-277
Language: Thai with English abstract
The collection of 31,783 strains of Vibrio cholerae isolated during a 17-year period (1980-1996) from hospitalized patients with severe diarrhea, received from different parts of Thailand, were confirmed and analyzed at Department of Medical Sciences. It was found that there were 3 periods of serotypes Ogawa-Inaba switching of V. cholerae 01, biotypeEI Tor. The first period: 1980-1981, Ogawa was predominant. Then the second period: 1982-1988, Ogawa was switched to Inaba and the third period: 1989-1996, the prevalent serotype in all three was Ogawa. Interestingly, three Hikojima isolates were emerged in 1994-1995. The V. cholerae new serogroup 0139 has also been detected from 1993 to 1996. It seems reasonable to assume that the same environmental pressures (host immune factors, etc.) that may have influenced the serotype conversion in V. cholerae 01, could also influence an 01-to-0139 shift. It appears to be more likely that any serotype-converted strains detected either were spontaneous Ogawa-to-Inaba or, alternatively, arose because of the ability of bacteriophage to mediate generalized transduction. In this case, it is possible that the phage transduce the serotype from one strain to another. From this study, it may be useful for the selection of local strains for basic sciences research for cholera vaccine development as a public health tool to prevention and control cholera in the future.