title: Assessing the origin of and potential for international spread of chikungunya virus from the Caribbean.
abstract: BACKGROUND
  For the first time, an outbreak of chikungunya has been reported in the Americas. Locally acquired infections have been confirmed in fourteen Caribbean countries and dependent territories, Guyana and French Guiana, in which a large number of North American travelers vacation. Should some travelers become infected with chikungunya virus, they could potentially introduce it into the United States, where there are competent Aedes mosquito vectors, with the possibility of local transmission.
  
  
  METHODS
  We analyzed historical data on airline travelers departing areas of the Caribbean and South America, where locally acquired cases of chikungunya have been confirmed as of May 12th, 2014. The final destinations of travelers departing these areas between May and July 2012 were determined and overlaid on maps of the reported distribution of Aedes aeygpti and albopictus mosquitoes in the United States, to identify potential areas at risk of autochthonous transmission.
  
  
  RESULTS
  The United States alone accounted for 52.1% of the final destinations of all international travelers departing chikungunya indigenous areas of the Caribbean between May and July 2012. Cities in the United States with the highest volume of air travelers were New York City, Miami and San Juan (Puerto Rico). Miami and San Juan were high travel-volume cities where Aedes aeygpti or albopictus are reported and where climatic conditions could be suitable for autochthonous transmission.
  
  
  CONCLUSIONS
  The rapidly evolving outbreak of chikungunya in the Caribbean poses a growing risk to countries and areas linked by air travel, including the United States where competent Aedes mosquitoes exist. The risk of chikungunya importation into the United States may be elevated following key travel periods in the spring, when large numbers of North American travelers typically vacation in the Caribbean.
authors.affiliation: Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, Canada.
authors.forename: Kamran
authors.initials: K
authors.lastname: Khan
authors.affiliation: Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, Canada; University Health Network, Divisions of Internal Medicine and Infectious Diseases, Toronto, Canada.
authors.forename: Isaac
authors.initials: I
authors.lastname: Bogoch
authors.affiliation: Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: John S
authors.initials: JS
authors.lastname: Brownstein
authors.affiliation: Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Miniota
authors.affiliation: Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada.
authors.forename: Adrian
authors.initials: A
authors.lastname: Nicolucci
authors.affiliation: Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada.
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.affiliation: Children's Hospital Informatics Program, Boston Children's Hospital, Boston, Massachusetts, USA ; Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA ; Network Dynamics and Simulation Science Laboratory, Virginia Bioinformatics Institute, Virginia Tech, Blacksburg, Virginia, USA
authors.forename: Elaine O
authors.initials: EO
authors.lastname: Nsoesie
authors.affiliation: Division of Global Migration and Quarantine, Centers for Disease Control and Prevention, Atlanta, USA; Departments of Medicine and Epidemiology, Emory University School of Medicine and Rollins School of Public Health, Atlanta, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Cetron
authors.affiliation: Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada.
authors.forename: Maria Isabella
authors.initials: MI
authors.lastname: Creatore
authors.affiliation: Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada.
authors.forename: Matthew
authors.initials: M
authors.lastname: German
authors.affiliation: Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore; Institute of Public Health, University of Heidelberg, Germany.
authors.forename: Annelies
authors.initials: A
authors.lastname: Wilder-Smith