Laboratory Protocols for Isolation and Identification of Toxigenic Strains of Vibrio cholerae: A Review

Vibrio cholerae is a pathogenic bacteria that accounts for diarrheal illness which can be life-threatening in lack of treatment and accounts for great morbidity and mortality. The common mode of transmission includes fecal-oral route transmission mediated through contaminated food and water. The strains 01 and 0139 have been associated with epidemic outbreak of cholera with severe clinical manifestation whereas the infection caused by non O1 and non O139 strains are recognized as non-epidemic cholera characterized by mild-severe diarrheal syndrome without epidemic potential. Laboratory diagnosis through Culture and determining Antimicrobial susceptibility tests are recommended for diagnosis of cholera in all clinical laboratory settings. The simple conventional laboratory diagnosis through culture should be effective for diagnosis of cholera in the resource (PCR) limited laboratories. However, Vibrio cholerae in VBNC (Viable but non-culturable) state can only be detected through molecular methods. Therefore, molecular methods need to be extended in all epidemiological laboratories for preventing misidentification of Vibrio cholerae especially from environmental samples. Epidemic outbreak of cholera has explained the need of immediate preparedness with preventive, diagnosis and curative improvement in all health sectors. Therefore, immediate health and sanitation related awareness are necessary for prompt control of the disease before it leads community to global burden.