BROAD INSTITUTEWhole-genome sequences of 110 Zika virus isolates from people and mosquitoes from 10 countries have allowed researchers to analyze the virus’s spread across the Americas. Combining the new sequences with 64 previously published genomes, the researchers tracked the origins of the Zika virus responsible for outbreaks in South America, Central America, the Caribbean, and the U.S., to a common ancestor in Brazil in 2014. From there, the virus formed genetically distinct clusters as it spread north, according to the analysis published yesterday (May 24) in Nature.
In regions including Colombia, Honduras, Puerto Rico, and the southern U.S., Zika appears to have been present for up to a year before the first reports of infections and associated microcephaly cases. “This means the outbreak in these regions was underway much earlier than previously thought,” coauthor Bronwyn MacInnis, associate director of malaria and viral genomics at the Broad Institute’s Infectious Disease and Microbiome Program, said during a telephone press briefing this week (via GenomeWeb).
Meanwhile, another study also published yesterday in Nature reports on 54 partial and complete Zika genomes—one of which represents the earliest confirmed Zika virus infection in Brazil—generated by a mobile genetics lab traveling through the northeastern part of the country last year. Again combining these data with previously published Zika ...