title: The incubation period of cholera: a systematic review.
abstract: OBJECTIVE
  Recent large cholera outbreaks highlight the need for improved understanding of the pathogenesis and epidemiology of cholera. The incubation period of cholera has important implications for clinical and public health decision-making, yet statements of the incubation period of cholera are often imprecise. Here we characterize the distribution of cholera's incubation period.
  
  
  METHODS
  We conducted a systematic review of the literature for statements of the incubation period of cholera and data that might aid in its estimation. We extracted individual-level data, parametrically estimated the distribution of toxigenic cholera's incubation period, and evaluated evidence for differences between strains.
  
  
  RESULTS
  The incubation period did not differ by a clinically significant margin between strains (except O1 El Tor Ogawa). We estimate the median incubation period of toxigenic cholera to be 1.4 days (95% CI, 1.3-1.6). Five percent of cholera cases will develop symptoms by 0.5 days (95% CI 0.4-0.5), and 95% by 4.4 days (95% CI 3.9-5.0) after infection.
  
  
  CONCLUSIONS
  We recommend that cholera investigations use a recall period of at least five days to capture relevant exposures; significantly longer than recent risk factor studies from the Haitian epidemic. This characterization of cholera's incubation period can help improve clinical and public health practice and advance epidemiologic research.
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA. aazman@jhsph.edu
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Azman
authors.forename: Kara E
authors.initials: KE
authors.lastname: Rudolph
authors.forename: Derek A T
authors.initials: DA
authors.lastname: Cummings
authors.forename: Justin
authors.initials: J
authors.lastname: Lessler
mesh_terms: D002771:Cholera / Q000382:microbiology* / Q000635:transmission*; D006801:Humans; D055256:Infectious Disease Incubation Period; D014734:Vibrio cholerae / Q000502:physiology*