Cholera in United States Associated with Epidemic in Hispaniola

Cholera caused by toxigenic Vibrio cholerae, serogroup O1, serotype Ogawa, biotype El Tor, was confirmed on October 21, 2010, in Haiti and on October 31, 2010, in the Dominican Republic. These countries are on the island of Hispaniola. During October 21, 2010–April 4, 2011, >275,000 cholera cases and >4,700 deaths were reported from Hispaniola. Of these cases, 840 culture-confirmed cases and 10 deaths were reported from the Dominican Republic. Illness caused by toxigenic V. cholerae O1 has been documented in the United States since 1832. During 1965–1991, an average of 5 cases per year were reported. During the Latin American cholera epidemic that started in 1991, the number of cholera cases in the United States increased because of importation of cases related to the epidemic to an average of 53 cases per year during 1992–1994 (1,2). As the Latin American epidemic waned, during 1995–2000, the average annual case count decreased to 10 (3). During 2000–2010, the average number of cases was 6, and 57% of case-patients had traveled internationally (4). This experience raised concern that a dramatic increase in US cholera cases could result from the Hispaniola epidemic. In the United States, cholera is confirmed by identification of toxigenic V. cholerae serogroup O1 or O139 or by serologic evidence of infection in a patient with diarrhea and an epidemiologic link to a culture-confirmed case. Since 2000, suspected V. cholerae isolates have been sent by state public health laboratories to the Centers for Disease Control and Prevention (CDC) for confirmation and characterization. We summarize characteristics of confirmed US cases associated with the Hispaniola epidemic that were reported to the CDC Cholera and Other Vibrio Illness Surveillance System, a national database of all laboratory-confirmed cholera and vibriosis cases. For each case of cholera, state and local health officials submit a Cholera and Other Vibrio Illness Surveillance System report form that contains demographic, clinical, and epidemiologic information, including selected food and water exposures associated with cholera, travel history, and vaccination status.