Re-emergence of cholera in Haiti linked to environmentalV. choleraeO1 Ogawa strains

BACKGROUNDOn September 25th, 2022, cholera re-emerged in Haiti.OBJECTIVES/METHODSToxigenicVibrio choleraeO1 Ogawa were isolated on October 3rd& 4th, 2022, from cholera case patients in Port-au-Prince. The two new genomes were compared with genomes from 2,129V. choleraeO1 isolated worldwide, including 292 Haitian strains from 2010-2018.RESULTSPhylogenies conclusively show the 2022 strains clustering within the Haitian monophyletic clade dating back to the 2010 outbreak. Strains shared a most recent common ancestor with a 2018 Haitian Ogawa strain isolated from the aquatic ecosystem, and cluster with the Ogawa clade that was circulating in 2015-2016.CONCLUSIONSRe-emergence of cholera in Haiti is the likely result of a spill-over event at the aquatic-human interface related to persistence ofV. choleraeO1 in the environment.One-Sentence SummaryWe analyzed the full genome of twoV. choleraestrains isolated from Haitian patients infected during the early days of the current 2022 epidemic, with data indicating that they originated from strains that have been circulating undetected at sub-epidemic levels in the aquatic environment.