Chen Rubing, Puri Vinita, Fedorova Nadia, Lin David, Hari Kumar L, Jain Ravi, Rodas Juan David, Das Suman R, Shabman Reed S, Weaver Scott C
Institute of Human Infections and Immunology and Department of Pathology, University of Texas Medical Branch, Galveston, Texas, USA.
J. Craig Venter Institute, Rockville, Maryland, USA.
J Virol. 2016 Nov 14;90(23):10600-10611. doi: 10.1128/JVI.01166-16. Print 2016 Dec 1.
Since the India and Indian Ocean outbreaks of 2005 and 2006, the global distribution of chikungunya virus (CHIKV) and the locations of epidemics have dramatically shifted. First, the Indian Ocean lineage (IOL) caused sustained epidemics in India and has radiated to many other countries. Second, the Asian lineage has caused frequent outbreaks in the Pacific islands and in 2013 was introduced into the Caribbean, followed by rapid spread to nearly all of the neotropics. Further, CHIKV epidemics, as well as exported cases, have been reported in central Africa after a long period of perceived silence. To understand these changes and to anticipate the future of the virus, the exact distribution, genetic diversity, transmission routes, and future epidemic potential of CHIKV require further assessment. To do so, we conducted the most comprehensive phylogenetic analysis to date, examined CHIKV evolution and transmission, and explored distinct genetic factors associated with the emergence of the East/Central/South African (ECSA) lineage, the IOL, and the Asian lineage. Our results reveal contrasting evolutionary patterns among the lineages, with growing genetic diversities observed in each, and suggest that CHIKV will continue to be a major public health threat with the potential for further emergence and spread.
Chikungunya fever is a reemerging infectious disease that is transmitted by Aedes mosquitoes and causes severe health and economic burdens in affected populations. Since the unprecedented Indian Ocean and Indian subcontinent outbreaks of 2005 and 2006, CHIKV has further expanded its geographic range, including to the Americas in 2013. Its evolution and transmission during and following these epidemics, as well as the recent evolution and spread of other lineages, require optimal assessment. Using newly obtained genome sequences, we provide a comprehensive update of the global distribution of CHIKV genetic diversity and analyze factors associated with recent outbreaks. These results provide a solid foundation for future evolutionary studies of CHIKV that can elucidate emergence mechanisms and also may help to predict future epidemics.
自2005年和2006年印度及印度洋地区疫情爆发以来，基孔肯雅病毒（CHIKV）的全球分布及疫情发生地点已发生显著变化。首先，印度洋谱系（IOL）在印度引发了持续疫情，并传播到许多其他国家。其次，亚洲谱系在太平洋岛屿频繁爆发疫情，并于2013年传入加勒比地区，随后迅速蔓延至几乎所有新热带地区。此外，在经历了长期看似平静之后，中非也报告了基孔肯雅病毒疫情以及输入病例。为了解这些变化并预测该病毒的未来走向，需要进一步评估基孔肯雅病毒的确切分布、遗传多样性、传播途径以及未来的流行潜力。为此，我们进行了迄今为止最全面的系统发育分析，研究了基孔肯雅病毒的进化与传播，并探索了与东非/中非/南非（ECSA）谱系、印度洋谱系和亚洲谱系出现相关的独特遗传因素。我们的结果揭示了各谱系之间截然不同的进化模式，且每个谱系的遗传多样性都在增加，并表明基孔肯雅病毒将继续成为重大公共卫生威胁，有可能进一步出现和传播。
基孔肯雅热是一种再度出现的传染病，通过伊蚊传播，给受影响人群带来严重的健康和经济负担。自2005年和2006年印度洋及印度次大陆前所未有的疫情爆发以来，基孔肯雅病毒进一步扩大了其地理范围，包括2013年传入美洲。在这些疫情期间及之后该病毒的进化与传播，以及其他谱系最近的进化与传播，都需要进行优化评估。利用新获得的基因组序列，我们全面更新了基孔肯雅病毒遗传多样性的全球分布情况，并分析了与近期疫情爆发相关的因素。这些结果为基孔肯雅病毒未来的进化研究提供了坚实基础，有助于阐明其出现机制，也可能有助于预测未来疫情。
