de Bruycker-Nogueira Fernanda, Mir Daiana, Dos Santos Flavia Barreto, Bello Gonzalo
Laboratory of Viral Immunology, Oswaldo Cruz Institute-FIOCRUZ, Av. Brasil 4365, 21045-900 Rio de Janeiro, RJ, Brazil.
Laboratory of AIDS & Molecular Immunology, Oswaldo Cruz Institute-FIOCRUZ, Av. Brasil 4365, 21045-900 Rio de Janeiro, RJ, Brazil.
Infect Genet Evol. 2016 Nov;45:454-460. doi: 10.1016/j.meegid.2016.09.025. Epub 2016 Oct 3.
The genotype V has been the most prevalent dengue virus type 1 (DENV-1) clade circulating in the Americas over the last 40years. In this study, we investigate the spatiotemporal pattern of emergence and dissemination of DENV-1 lineages in the continent. We applied phylogenetic and phylogeographic approaches to a comprehensive data set of 836 DENV-1 E gene sequences of the genotype V isolated from 46 different countries around the world over a period of 50years (1962 to 2014). Our study reveals that genetic diversity of DENV-1 genotype V in the Americas resulted from two independent introductions of this genotype from India. The first genotype V strain was most probably introduced into the Lesser Antilles at around the early 1970s and this Caribbean region becomes the source population of several DENV-1 lineages that spread in the Americas during the 1970s and 1980s. Most of those lineages appear to become extinct during the 1990s, except one that persisted in Venezuela and later spread to other American countries, dominating the DENV-1 epidemics in the region from the early 2000s onwards. The second genotype V strain of Indian origin was also most probably introduced into the Lesser Antilles at around the early 1980s. This lineage remained almost undetected for nearly 15years, until it was introduced in Northern Brazil around the middle 1990s and later spread to other country regions. These results demonstrate that different geographic regions have played a role in maintaining and spreading the DENV-1 genotype V in the Americas over time. DENV-1 genotype V lineages have originated, spread and died out in the Americas with very different dynamics and the phenomenon of lineage replacement across successive DENV-1 epidemic outbreaks was a common characteristic in most American countries.
基因型V是过去40年在美洲传播最广泛的1型登革病毒（DENV-1）进化枝。在本研究中，我们调查了该大陆DENV-1谱系出现和传播的时空模式。我们对50年（1962年至2014年）期间从全球46个不同国家分离出的836个基因型V的DENV-1 E基因序列的综合数据集应用了系统发育和系统地理学方法。我们的研究表明，美洲DENV-1基因型V的遗传多样性源于该基因型从印度的两次独立引入。第一个基因型V毒株很可能在20世纪70年代初左右被引入小安的列斯群岛，这个加勒比地区成为了20世纪70年代和80年代在美洲传播的几个DENV-1谱系的源种群。这些谱系中的大多数似乎在20世纪90年代灭绝，只有一个在委内瑞拉持续存在，后来传播到其他美洲国家，从21世纪初开始主导该地区的DENV-1疫情。第二个印度起源的基因型V毒株也很可能在20世纪80年代初左右被引入小安的列斯群岛。这个谱系在近15年里几乎未被发现，直到20世纪90年代中期左右被引入巴西北部，后来传播到其他国家地区。这些结果表明，随着时间的推移，不同地理区域在美洲DENV-1基因型V的维持和传播中发挥了作用。DENV-1基因型V谱系在美洲以非常不同的动态起源、传播和灭绝，并且在大多数美洲国家，连续的DENV-1疫情爆发中的谱系替代现象是一个共同特征。
