Emerging Pathogens Institute, University of Florida, Gainesville, Florida, United States of America.
Department of Environmental and Global Health, College of Public Health and Health Professions, University of Florida, Gainesville, Florida, United States of America.
PLoS One. 2018 May 10;13(5):e0196857. doi: 10.1371/journal.pone.0196857. eCollection 2018.
As part of on-going arboviral surveillance activity in a semi-rural region in Haiti, Chikungunya virus (CHIKV)-positive mosquito pools were identified in 2014 (the peak of the Caribbean Asian-clade epidemic), and again in 2016 by RT-PCR. In 2014, CHIKV was only identified in Aedes aegypti (11 positive pools/124 screened). In contrast, in sampling in 2016, CHIKV was not identified in Ae. aegypti, but, rather, in (a) a female Aedes albopictus pool, and (b) a female Culex quinquefasciatus pool. Genomic sequence analyses indicated that the CHIKV viruses in the 2016 mosquito pools were from the East-Central-South African (ECSA) lineage, rather than the Asian lineage. In phylogenetic studies, these ECSA lineage strains form a new ECSA subgroup (subgroup IIa) together with Brazilian ECSA lineage strains from an isolated human outbreak in 2014, and a mosquito pool in 2016. Additional analyses date the most recent common ancestor of the ECSA IIa subgroup around May 2007, and the 2016 Haitian CHIKV genomes around December 2015. Known CHIKV mutations associated with improved Ae. albopictus vector competence were not identified. Isolation of this newly identified lineage from Ae. albopictus is of concern, as this vector has a broader geographic range than Ae. aegypti, especially in temperate areas of North America, and stresses the importance for continued vector surveillance.
作为海地半农村地区正在进行的虫媒病毒监测活动的一部分，2014 年（加勒比亚洲谱系流行的高峰期）和 2016 年通过 RT-PCR 鉴定出基孔肯雅病毒（CHIKV）阳性蚊池。2014 年，仅在埃及伊蚊（Aedes aegypti）中鉴定出 CHIKV（124 个筛查中有 11 个阳性池）。相比之下，在 2016 年的采样中，Ae. aegypti 中未鉴定出 CHIKV，但在（a）白纹伊蚊（Aedes albopictus）雌性蚊池中，和（b）库蚊（Culex quinquefasciatus）雌性蚊池中鉴定出 CHIKV。基因组序列分析表明，2016 年蚊池中分离的 CHIKV 病毒属于东中非-南非（ECSA）谱系，而不是亚洲谱系。在系统发育研究中，这些 ECSA 谱系菌株与 2014 年巴西孤立的人类暴发中的 ECSA 谱系菌株以及 2016 年的一个蚊池一起形成了一个新的 ECSA 亚组（亚组 IIa）。进一步分析表明，ECSA IIa 亚组的最近共同祖先出现在 2007 年 5 月左右，而海地 2016 年 CHIKV 基因组则出现在 2015 年 12 月左右。尚未发现与埃及伊蚊传播能力增强相关的已知 CHIKV 突变。从埃及伊蚊中分离出这种新鉴定的谱系令人担忧，因为这种媒介的地理分布范围比埃及伊蚊更广，特别是在北美的温带地区，这强调了继续进行媒介监测的重要性。
