Understanding the cholera epidemic, Haiti

Abstract

After the devastating outbreak of cholera in Haiti in mid-October 2010, several hypotheses have emerged regarding the origin of the outbreak. Some articles and media reports pointed to the United Nations peacekeepers from Nepal as the source. Piarroux et al. drew a similar conclusion from their epidemiologic study (1). Nepal did experience an outbreak of cholera during August–October 2010, in which 72 cases of infection with Vibrio cholerae O1, serotype Ogawa, were confirmed, mostly among young adult males. The cases peaked from mid-September to early October (Figure; Figure A1), and no deaths occurred. Despite this similarity in timing, I believe several points need to be considered before a firm conclusion is reached.

Figure

Patients with confirmed and suspected cases of cholera admitted to Sukraraj Tropical and Infectious Disease Hospital, by week, Katmandu, Nepal, July–November 2010. Case definitions: suspected cholera, acute watery diarrhea, with or without vomiting, in a child >5 years of age; confirmed cholera, isolation of Vibrio cholerae O1 or O139 from feces of any patient with diarrhea.

Figure A1

Patients with confirmed cases of cholera admitted to Sukraraj Tropical and Infectious Disease Hospital, by age group, Katmandu, Nepal, July–November 2010.