Dengue and Chikungunya Group, ICMR-National Institute of Virology, Pune, Maharashtra, India.
Bioinformatics and Data Management Group, ICMR-National Institute of Virology, Pune, Maharashtra, India.
J Med Virol. 2023 Nov;95(11):e29253. doi: 10.1002/jmv.29253.
A surge in chikungunya was observed during 2020-21 in Pune district of Maharashtra, India. Whole genome sequencing and phylogenetic analysis of 21 samples/sequences revealed them as Indian ocean lineage of East Central South African genotype. Two distinct sequence clusters were found to circulate during 2020-21; one with E1:K211E and E2:V264A mutations while the other had E1:I317V mutation along with E1:K211E and E2: V264A mutations. The former, the predominant cluster (n = 18), clustered with chikungunya virus (CHIKV) strains of pre 2014 period while the latter (n = 3) clustered with 2016-2018 period Indian strains. Though E1: A226V was not detected in any of the 21 sequences, several unique mutations were detected in the strains which might have played key roles in the enhanced virus transmission during the period. The study highlights parallel evolution, introduction from the neighboring regions and cocirculation of two sequence clusters of CHIKV in Pune. The complete genome data can be useful to determine how the circulating strains differ from candidate vaccines and might help to predict the protective efficacy of chikungunya vaccine candidates.
2020-2021 年，印度马哈拉施特拉邦浦那地区观察到基孔肯雅热疫情上升。对 21 个样本/序列进行全基因组测序和系统发育分析，结果显示它们属于印度洋东中非基因型。发现 2020-2021 年期间存在两个不同的序列群；一个群具有 E1:K211E 和 E2:V264A 突变，另一个群则具有 E1:I317V 突变以及 E1:K211E 和 E2:V264A 突变。前者（n=18）是主要的聚类，与 2014 年前的基孔肯雅热病毒（CHIKV）株聚类，而后者（n=3）与 2016-2018 年印度株聚类。虽然在 21 个序列中均未检测到 E1:A226V，但在这些菌株中检测到了几个独特的突变，这些突变可能在该时期增强病毒传播中发挥了关键作用。本研究强调了 CHIKV 在浦那的平行进化、来自邻近地区的传入以及两个序列群的共同传播。完整的基因组数据可用于确定循环株与候选疫苗的差异，并有助于预测基孔肯雅热候选疫苗的保护效力。
