R. R. Frerichs Department of Epidemiology, UCLA School of Public Health, Los Angeles, CA, USA.
P.S. Keim Division of Pathogens Genomics, Translational Genomics Research Institute (TGen), Flagstaff, AZ, USA, and Center for Microbial Genetics and Genomics, Northern Arizona University, Flagstaff, AZ, USA.
R. BarraisMinistry of Public Health and Population, Port-au-Prince, Haiti.
R. PiarrouxDepartment of Parasitology, Aix Marseille University, Marseille, France.
Cholera appeared in Haiti in October 2010 for the first time in recorded history. The causative agent was quickly identified by the Haitian National Public Health Laboratory (LNSP) and the United States Centers for Disease Control and Prevention (CDC) as Vibrio cholerae serogroup O1, serotype Ogawa, biotype El Tor. Since then, over one-half million government-acknowledged cholera cases and more than seven thousand deaths have occurred, the largest cholera epidemic in the world, with the real death toll likely being much higher. Questions of origin have been widely debated with some attributing the onset of the epidemic to climatic factors and others to human transmission. None of the evidence on origin supports climatic factors. Instead, recent epidemiological and molecular-genetic evidence point to the United Nations (UN) peacekeeping troops from Nepal as the source of cholera to Haiti, following their troop rotation in early October 2010. Such findings have important policy implications for shaping future international relief efforts.