Results of analysis of cholera outbreak during which V. cholerae O1 biovar El-Tor ctxAB- tcpA+ was isolated from 2 patients and 30 carriers are presented. Epidemic was caused by contamination of water source and water route of transmission. Strains identical to ones detected in humans were isolated from water of surface well in zone of water intake. Genome and VNTR-analysis of ctxAB- tcpA+ vibrios that caused outbreak in Rostov region in 2005 showed that they differed from ctxAB- tcpA- and ctxAB- tcpA+ vibrios isolated previously during and beyond of outbreaks from patients, carriers and environment and formed separate group with certain genotype. These results confirms conclusions of epidemiological analysis about imported cause of recent outbreak.