Robust genomic sequencing analysis greatly bolsters the case that the cholera epidemic in Haiti that began late in 2010 was caused by a strain of Vibrio cholerae from Nepal, according to a team of Danish, American, and Nepalese investigators. These findings “highlight how rapidly infectious diseases might be transmitted globally through international travel and how public health officials need advanced molecular tools along with standard epidemiological analyses to quickly determine the sources of the outbreak,” note Frank M. Aarestrup of the Technical University of Denmark in Lyngby, Paul Keim of Northern Arizona University in Flagstaff, and their collaborators at those institutions and at the National Public Health Laboratory in Kathmandu, Nepal. Their report appears in the July-August 2011 mBio (doi:10.1128/mBio.00157–11).