Project Directorate on Foot and Mouth Disease, Mukteswar-Kumaon, Nainital 263138, Uttarakhand, India.
Vet Microbiol. 2013 Dec 27;167(3-4):280-8. doi: 10.1016/j.vetmic.2013.08.023. Epub 2013 Sep 6.
Foot and mouth disease virus (FMDV) serotype Asia1 was first identified in India in 1951 and since then causing significant proportion of FMD outbreaks in the country. In this paper genetic analysis of 219 isolates from India collected over a period of 48 years is described. Bayesian approach was used to estimate the date of divergence and evolutionary rate. Phylogenetic analysis indicated the circulation of three lineages (B, C and D) of which lineage B formed one genotype (I) which was prevalent during 1964-2000. Genotype II constituted by lineage C and D has been in circulation since 1979 till date. We observed dramatic form of clade turnover in serotype Asia1 in India. The time scale analysis indicated that the most recent common ancestors for Indian Asia1 strains existed around 77 years ago. The evolutionary rate of serotype Asia1 viruses (genotype II) from India was estimated at 5.871×10(-3) substitutions per site, per year. We observed several connections in our phylogeographic analysis indicating intense flow of virus among states. The antigenically critical sites were frequently substituted and positive selection was evident at many sites. Maximum likelihood analysis suggested that the strains circulating in the country since 2005 were different from the genetic groups (I-VII) identified earlier and designated here as Group VIII.
口蹄疫病毒（FMDV）血清型亚洲 1 型于 1951 年在印度首次被发现，自此以后，该病毒成为该国口蹄疫爆发的主要原因之一。本文描述了对印度在 48 年间收集的 219 个分离株的遗传分析。采用贝叶斯方法估计了分歧时间和进化率。系统进化分析表明，存在三个谱系（B、C 和 D）的循环，其中谱系 B 形成一个基因型（I），在 1964-2000 年期间流行。由谱系 C 和 D 组成的基因型 II 自 1979 年以来一直存在至今。我们观察到印度口蹄疫血清型亚洲 1 型中明显的分支更替形式。时间尺度分析表明，印度亚洲 1 型毒株的最近共同祖先存在于大约 77 年前。来自印度的口蹄疫血清型亚洲 1 型病毒（基因型 II）的进化率估计为每年每一位点 5.871×10(-3)个替换。我们在系统地理学分析中观察到了几个连接，表明病毒在各州之间的频繁流动。抗原关键位点经常被取代，许多位点存在明显的正选择。最大似然分析表明，自 2005 年以来在该国流行的菌株与之前确定的遗传群（I-VII）不同，这里将其指定为第八组。
