Regional Medical Research Centre, Chandrasekharpur, Bhubaneswar 751023, Orissa, India.
Infect Genet Evol. 2012 Jul;12(5):1094-101. doi: 10.1016/j.meegid.2012.03.012. Epub 2012 Mar 29.
Chikungunya virus (CHIKV), an arthritogenic alphavirus, is transmitted to humans by mosquitoes of genus Aedes, mainly Aedes aegypti and Aedes albopictus. The resurgence of CHIKV in different parts of India is a point of major public health concern. In 2010, chikungunya outbreaks with high epidemic magnitude were recorded in coastal areas of Orissa, Eastern India, affecting more than 15,000 people coupled with severe arthralgia and prolonged morbidites. Detailed entomological, serological and molecular investigation of this unprecendented outbreak was carried out by collecting and studying 1359 mosquito samples belonging to A. albopictus, A. aegypti, A. vittatus, A. edwardsii and Culex species and 220 patients serum from the affected areas. In this study, CHIKV specific IgM capture-ELISA and reverse-transcription PCR (RT-PCR) were done to detect recent infection of CHIKV in serum samples and adult mosquitoes collected from the affected areas. The high maximum likelihood estimate (MLE) (15.2) in A. albopictus mosquitoes indicated that it was the principal vector involved in transmission of CHIKV in Orissa. Phylogenetic analysis revealed that the CHIKV strains involved in the outbreak belonged to the Indian Ocean Lineage (IOL) group within the East, Central and South African (ECSA) genotype. Genetic characterization of envelope glycoprotein (E1 and E2) genes revealed that all the CHIKV isolates from Orissa had the E1-A226V mutation that enhances viral dissemination and transmissibility by A. albopictus mosquitoes along with E2-L210Q and E2-I211T mutations, which play an epistatic role with E1-A226V mutation in adaptation of CHIKV to A. albopictus by increasing its midgut infectivity, thereby favoring its vectorial capacity. Our results showed the involvement of A. albopictus vector in the recent outbreaks in Orissa and circulation of IOL strains of ECSA genotype of CHIKV with E1-A226V, E2-L210Q and E2-I211T mutations in vectors and patients serum.
基孔肯雅病毒（CHIKV）是一种致关节炎的甲病毒，主要通过埃及伊蚊和白纹伊蚊属的蚊子传播给人类。CHIKV 在印度不同地区的再次出现是一个主要的公共卫生关注点。2010 年，印度东部奥里萨邦沿海地区爆发了具有高流行规模的基孔肯雅热疫情，超过 15000 人受到影响，伴有严重的关节炎和长期的病态。通过收集和研究来自受影响地区的 1359 只属于白纹伊蚊、埃及伊蚊、A. vittatus、A. edwardsii 和库蚊属的蚊子样本和 220 名患者血清，对这一前所未有的疫情进行了详细的昆虫学、血清学和分子调查。在这项研究中，使用 CHIKV 特异性 IgM 捕获 ELISA 和逆转录 PCR（RT-PCR）检测血清样本和从受影响地区采集的成年蚊子中 CHIKV 的近期感染情况。白纹伊蚊的最大似然估计值（MLE）（15.2）很高，表明它是在奥里萨邦传播 CHIKV 的主要媒介。系统发育分析显示，疫情中涉及的 CHIKV 株属于印度洋谱系（IOL）组，属于东、中、南非（ECSA）基因型。包膜糖蛋白（E1 和 E2）基因的遗传特征表明，来自奥里萨邦的所有 CHIKV 分离株都具有 E1-A226V 突变，该突变增强了病毒通过白纹伊蚊的传播和传染性，同时还具有 E2-L210Q 和 E2-I211T 突变，这些突变与 E1-A226V 突变在适应白纹伊蚊方面发挥着上位作用，通过增加其中肠感染力，从而提高其媒介能力。我们的结果表明，白纹伊蚊媒介参与了奥里萨邦的最近疫情爆发，以及 ECSA 基因型的 IOL 株的循环，这些病毒株在媒介和患者血清中具有 E1-A226V、E2-L210Q 和 E2-I211T 突变。
