Search

Zika virus (ZIKV) is a mosquito-borne flavivirus first isolated in Uganda in 1947. Although entomological and virologic surveillance have reported ZIKV enzootic activity in diverse countries of Africa and Asia, few human cases were reported until 2007, when a Zika fever epidemic took place in Micronesia. In the context of West Africa, the WHO Collaborating Centre for Arboviruses and Hemorrhagic Fever at Institut Pasteur of Dakar (http://www.pasteur.fr/recherche/banques/ CRORA/) reports the periodic circulation of ZIKV since 1968. Despite several reports on ZIKV, the genetic relationships among viral strains from West Africa remain poorly understood. To evaluate the viral spread and its molecular epidemiology, we investigated 37 ZIKV isolates collected from 1968 to 2002 in six localities in Senegal and Cote d’Ivoire. In addition, we included strains from six other countries. Our results suggested that these two countries in West Africa experienced at least two independent introductions of ZIKV during the 20 century, and that apparently these viral lineages were not restricted by mosquito vector species. Moreover, we present evidence that ZIKV has possibly undergone recombination in nature and that a loss of the N154 glycosylation site in the envelope protein was a possible adaptive response to the Aedes dalzieli vector. Citation: Faye O, Freire CCM, Iamarino A, Faye O, de Oliveira JVC, et al. (2014) Molecular Evolution of Zika Virus during Its Emergence in the 20 Century. PLoS Negl Trop Dis 8(1): e2636. doi:10.1371/journal.pntd.0002636 Editor: Brian Bird, Centers for Disease Control and Prevention, United States of America Received March 4, 2013; Accepted November 27, 2013; Published January 9, 2014 Copyright: 2014 Faye et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This study was made possible by the Institute Pasteur of Dakar in Senegal, FAPESP (Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, Brazil) projects #00/04205-6 (VGDN program), #08/17013-6 and #10/19341-4. CCMF has a CAPES studentship, AI (project #12/04818-5) and JVCdO received FAPESP scholarships and PMAZ holds a CNPq-PQ grant. Funding was also provided by NIH grant R01-AI069145. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. * E-mail: asall@pasteur.sn . These authors contributed equally to this work.