Epidemiological Update - Cholera - 11 October 2018

Summary of the situation

In 2017, a total of 13,803 suspected cases of cholera were reported on the island of Hispaniola: 13,681 cases (including 159 deaths) in Haiti and 122 cases (including 4 deaths) in the Dominican Republic. To date in 2018, a total of 3,224 suspected cholera cases have been reported in Hispaniola, 96% in Haiti. In addition, Mexico reported a cholera case in June 2018.

The following is a summary of the situation in each country.

In Haiti between epidemiological week (EW) 1 and EW 36 of 2018, 3,111 suspected cases were reported (Figure 1), including 37 deaths. The incidence rate for 2018 (until EW 36) is 25.5 cases per 100,000 population, which is the lowest recorded incidence since the beginning of the outbreak. Following the increase in cases that were reported in EW 19, a decrease has been observed, with a weekly average of 35 suspected cases reported over the last 8 weeks (EW 29 to EW 36). The cumulative case-fatality rate (CFR) has remained around 1% since 2011.

In the Dominican Republic, between EW 1 and EW 38 of 2018, 113 suspected cases of cholera were reported, representing an incidence rate of 1.52 cases per 100,000 population; this incidence rate is greater than the incidence rate reported for the same period in 2017 (1.43 cases per 100,000 population). Of the cases reported this year, 77% (n= 87) correspond to an outbreak that affected the province of Independencia between July and August 2018. In 2018, one death has been reported related to the outbreak in the province of Independencia.

In June 2018, Mexico reported one case of cholera (Vibrio cholerae O1 toxigenic) in a 43-year-old female patient who acquired the infection in Sinaloa. Molecular characterization showed that the isolated strain for this case is related to the V. cholerae O1 serotype Inaba strain that circulated in Hidalgo State during 2014 with one isolated case, and that it is not epidemiologically related to the V. cholerae O1 Ogawa strain that circulated during the 2013 outbreak in Hidalgo. No additional cases were reported.