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Objective of the study was to monitor the spread of cholera in the world, in the CIS countries and in Russia with an assessment of risks and emergencies that contribute to the activation of the epidemic process. Despite the downward trend in the global incidence rate of cholera during the period between 2010 and 2019, epidemics and major outbreaks occurred in 96 countries. WHO has reported 2013 imported cases of cholera to countries in Asia, the Americas, including the Caribbean, Europe, and Australia with Oceania; cholera-endemic administrative territories are identified in 24 countries. According to WHO, cholera burden reduction in Asia and Africa is associated with large-scale vaccination. During epidemiological surveillance of cholera, 705 strains of V. cholerae O1 and O139 serogroups were isolated from surface reservoirs in 26 constituent entities of the Russian Federation, including 10 strains of V. cholerae O1 ctxA+tcpA+, 35 strains of V. cholerae O1 ctxA–tcpA+, 655 strains of V. cholerae O1 ctxA–tcpA– , and five strains of V. cholerae O139 ctxA–tcpA–. Identification of strains with unique, previously unknown INDEL genotypes testifies to their imported nature. The forecast for cholera in the world for 2020, given the proven high degree of epidemic process activation at the expense of social and environmental risks caused by emergencies of different origin, the presence of endemic foci, infection import and other risk factors is unfavorable. For Russia, the forecast for cholera will be determined by the presence of external risks created by the ongoing 7-th pandemic, possible importation of infection to constituent entities of the Russian Federation that differ by the types of epidemic manifestations.

The trend of morbidity reduction at an average annual rate of 1.113 % in 2017 (in comparison to 2008) continues. The tendency of intensive monthly cholera incidence growth around the world in 2017 in relation to 2015 and 2016 is established. 25 countries with 70 endemic areas and 11734 imported cases of cholera onto different continents with predominance of interstate carrying of infection in Asia were identified. In Russia in 2008, 2010, 2012 and 2014 cholera importations from India have been registered. V. cholerae O1 biovar El Tor ctxA–tcpA–, ctxA–tcpA+, V. cholerae O139 ctxA– and tcpA– and singular V. cholerae O1 biovar El tor ctxA+tcpA+ strains were isolated from surface water bodies. INDEL typing of 242 V. cholerae O1 strains, isolated from environmental objects (2014–2017), provided the data which confirmed their belonging to common cluster of V. cholerae O1 ctxA–tcpA+. Along with genetic diversity of V. cholerae O1 ctxA–tcpA–, several strains of the same or closely related genotypes in some regions were isolated every year. For the first time ever the algorithm for risk of epidemic process activation assessment in case of cholera in Russia, taking into account the various factors (conditions), their gradation and expert scores, has been developed for the prediction. The forecast for cholera at the global level and in Russia for 2018 is unfavorable.

Analysis of epidemiological situation on cholera around the world has demonstrated downward trend in morbidity rates in 2016; annual average decline being 3.907 % (by reference to 2007). Comparative assessment of monthly incidence in 2015 and 2016 shows perennial registration of cholera cases in a number of African countries and in the Caribbean with up-rises in different seasons. Establishment of epidemic foci is on-going. Between 2007 and 2016, 1733 imported cases of cholera took place across the globe. Interstate import dominated in Asia. For forecast development, for the first time ever, risk assessment of epidemic process activation has been performed, taking into consideration emergency situations of varying origin, social and natural environments, using expert evaluation scores. Epidemic manifestations of cholera in the Russian Federation were characterized by import of the infection in 2008, 2010, 2012, and 2014; isolation of V. cholerae O1 biovar El Tor ctxA– tcpA–, ctxA+ and V. cholerae O139 ctxA– and tcpA– from surface water bodies, as well as individual V. cholerae O1 biovar El Tor сtхA+ tсра+. Worked out has been the algorithm for epidemiological investigation of causes and conditions of surface water body contamination with cholera vibrios. Cholera forecast worldwide and in Russia for the year 2017 remains unfavorable.