# name
Understanding the evolution and spread of chikungunya virus in
                the Americas using complete genome sequences

# metadata.dc.description.abstract[].value
Local transmission of chikungunya virus (CHIKV) was first
                detected in the Americas in December 2013, after which it spread
                rapidly throughout the Caribbean islands and American mainland,
                causing a major chikungunya fever epidemic. Previous
                phylogenetic analysis of CHIKV from a limited number of
                countries in the Americas suggests that an Asian genotype strain
                was responsible, except in Brazil where both Asian and
                East/Central/South African (ECSA) lineage strains were detected.
                In this study, we sequenced thirty-three complete CHIKV genomes
                from viruses isolated in 2014 from fourteen Caribbean islands,
                the Bahamas and two mainland countries in the Americas.
                Phylogenetic analyses confirmed that they all belonged to the
                Asian genotype and clustered together with other Caribbean and
                mainland sequences isolated during the American outbreak,
                forming an 'Asian/American' lineage defined by two amino acid
                substitutions, E2 V368A and 6K L20M, and divided into two
                well-supported clades. This lineage is estimated to be evolving
                at a mean rate of 5 x 10-4 substitutions per site per year (95%
                higher probability density, 2.9-7.9 x 10-4) and to have arisen
                from an ancestor introduced to the Caribbean (most likely from
                Oceania) in about March 2013, 9 months prior to the first report
                of CHIKV in the Americas. Estimation of evolutionary rates for
                individual gene regions and selection analyses indicate that (in
                contrast to the Indian Ocean Lineage that emerged from the ECSA
                genotype followed by adaptive evolution and with a significantly
                higher substitution rate) the evolutionary dynamics of the
                Asian/American lineage are very similar to the rest of the Asian
                genotype and natural selection does not appear to have played a
                major role in its emergence. However, several codon sites with
                evidence of positive selection were identified within the
                non-structural regions of Asian genotype sequences outside of
                the Asian/American lineage.

# metadata.dc.relation.isformatof[].value
Reproducció del document publicat a:
                http://dx.doi.org/10.1093/ve/vex010

# metadata.dc.relation.ispartof[].value
Virus Evolution, 2017, vol. 3, num. 1, p. vex010

# metadata.dc.source[].value
Articles publicats en revistes (ISGlobal)

# metadata.dc.title[].value
Understanding the evolution and spread of chikungunya virus in
                the Americas using complete genome sequences