Travel-Associated Zika Virus Disease Acquired in the Americas Through February 2016: A GeoSentinel Analysis

Ann Intern Med. 2017 Jan 17;166(2):99-108. doi: 10.7326/M16-1842. Epub 2016 Nov 22.


Background: Zika virus has spread rapidly in the Americas and has been imported into many nonendemic countries by travelers.

Objective: To describe clinical manifestations and epidemiology of Zika virus disease in travelers exposed in the Americas.

Design: Descriptive, using GeoSentinel records.

Setting: 63 travel and tropical medicine clinics in 30 countries.

Patients: Ill returned travelers with a confirmed, probable, or clinically suspected diagnosis of Zika virus disease seen between January 2013 and 29 February 2016.

Measurements: Frequencies of demographic, trip, and clinical characteristics and complications.

Results: Starting in May 2015, 93 cases of Zika virus disease were reported. Common symptoms included exanthema (88%), fever (76%), and arthralgia (72%). Fifty-nine percent of patients were exposed in South America; 71% were diagnosed in Europe. Case status was established most commonly by polymerase chain reaction (PCR) testing of blood and less often by PCR testing of other body fluids or serology and plaque-reduction neutralization testing. Two patients developed Guillain-Barré syndrome, and 3 of 4 pregnancies had adverse outcomes (microcephaly, major fetal neurologic abnormalities, and intrauterine fetal death).

Limitation: Surveillance data collected by specialized clinics may not be representative of all ill returned travelers, and denominator data are unavailable.

Conclusion: These surveillance data help characterize the clinical manifestations and adverse outcomes of Zika virus disease among travelers infected in the Americas and show a need for global standardization of diagnostic testing. The serious fetal complications observed in this study highlight the importance of travel advisories and prevention measures for pregnant women and their partners. Travelers are sentinels for global Zika virus circulation and may facilitate further transmission.

Primary funding source: Centers for Disease Control and Prevention, International Society of Travel Medicine, and Public Health Agency of Canada.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Caribbean Region / epidemiology
  • Central America / epidemiology
  • Child
  • Child, Preschool
  • Female
  • Guillain-Barre Syndrome / epidemiology
  • Guillain-Barre Syndrome / virology
  • Humans
  • Male
  • Middle Aged
  • Pregnancy
  • Pregnancy Complications, Infectious / epidemiology
  • Pregnancy Complications, Infectious / virology
  • Sentinel Surveillance*
  • South America / epidemiology
  • Travel*
  • Young Adult
  • Zika Virus Infection / complications
  • Zika Virus Infection / epidemiology*