Maximum Containment Laboratory, ICMR-National Institute of Virology, Sus Road, Pashan, Pune, 411021, India.
Bioinformatics Group, ICMR-National Institute of Virology, Pune, 411001, India.
Sci Rep. 2020 Feb 6;10(1):1966. doi: 10.1038/s41598-020-58242-w.
The Kyasanur Forest Disease (KFD) has become a major public health problem in the State of Karnataka, India where the disease was first identified and in Tamil Nadu, Maharashtra, Kerala, and Goa covering the Western Ghats region of India. The incidence of positive cases and distribution of the Kyasanur Forest Disease virus (KFDV) in different geographical regions raises the need to understand the evolution and spatiotemporal transmission dynamics. Phylogeography analysis based on 48 whole genomes (46 from this study) and additionally 28 E-gene sequences of KFDV isolated from different regions spanning the period 1957-2017 was thus undertaken. The mean evolutionary rates based the E-gene was marginally higher than that based on the whole genomes. A subgroup of KFDV strains (2006-2017) differing from the early Karnataka strains (1957-1972) by ~2.76% in their whole genomes and representing spread to different geographical areas diverged around 1980. Dispersal from Karnataka to Goa and Maharashtra was indicated. Maharashtra represented a new source for transmission of KFDV since ~2013. Significant evidence of adaptive evolution at site 123 A/T located in the vicinity of the envelope protein dimer interface may have functional implications. The findings indicate the need to curtail the spread of KFDV by surveillance measures and improved vaccination strategies.
基孔肯雅热（KFD）已成为印度卡纳塔克邦（印度首次发现该疾病的州）和泰米尔纳德邦、马哈拉施特拉邦、喀拉拉邦和果阿邦（印度西高止山脉地区）的一个主要公共卫生问题。阳性病例的发生率和基孔肯雅热病毒（KFDV）在不同地理区域的分布情况，使得人们有必要了解其进化和时空传播动态。因此，对基于 48 个全基因组（本研究中的 46 个）和另外 28 个来自不同地区的 E 基因序列的 KFDV 进行了系统发育地理分析，这些地区涵盖了 1957 年至 2017 年的时间范围。基于 E 基因的平均进化率略高于基于全基因组的进化率。KFDV 株的一个亚组（2006-2017 年）与早期的卡纳塔克邦株（1957-1972 年）在全基因组上存在约 2.76%的差异，代表了向不同地理区域的传播，大约在 1980 年左右发生分歧。表明从卡纳塔克邦向果阿邦和马哈拉施特拉邦的传播。马哈拉施特拉邦自 2013 年以来代表了 KFDV 传播的新来源。位于包膜蛋白二聚体界面附近的 123 A/T 位点的适应性进化的显著证据可能具有功能意义。这些发现表明，需要通过监测措施和改进的疫苗接种策略来遏制 KFDV 的传播。
