Tosh C, Sanyal A, Hemadri D, Venkataramanan R
Project Directorate on Foot-and-Mouth Disease, Indian Veterinary Research Institute Campus, Mukteswar-Kumaon, Nainital, India.
Arch Virol. 2002 Mar;147(3):493-513. doi: 10.1007/s007050200002.
The genetic diversity among the Indian serotype A Foot-and-mouth disease virus (FMDV) isolates sampled over a period of 24 years (1977-2000) was studied by sequencing the VP1 gene. In the phylogenetic tree, constructed from 83 Indian and 37 other available sequences, the FMDV type A isolates were distributed into 10 major genotypes (designated as I-X). The Indian isolates were distributed in 4 genotypes (I, IV, VI and VII), and co-circulation of at least 2 genotypes (VI and VII) in different states of the country in recent years is evident from the result. The study also revealed differential geographic distribution of genotypes, for example, some (genotypes I and VII) were recovered from large geographical areas, some time even across the continents, suggesting the spread of the viruses beyond continental barriers. Localization of genotypes restricting to a particular country (genotypes III and X) was also observed in the study. The genetic diversity in the field isolates has been discussed in relation to the amino acid substitutions at the known antigenic sites. This work provides valuable insights into the epidemiological situation of type A FMDV in India and necessary information in the selection of suitable vaccine strain(s), if required, for the National FMD control program.
通过对VP1基因进行测序，研究了在24年（1977 - 2000年）期间采集的印度A 型口蹄疫病毒（FMDV）分离株之间的遗传多样性。在由83个印度序列和37个其他可用序列构建的系统发育树中，A 型FMDV分离株被分为10个主要基因型（命名为I - X）。印度分离株分布在4个基因型（I、IV、VI和VII）中，结果表明近年来该国不同邦至少有2个基因型（VI和VII）共同流行。该研究还揭示了基因型的不同地理分布，例如，一些（基因型I和VII）从大片地理区域分离得到，有时甚至跨越各大洲，这表明病毒跨越了大陆屏障传播。研究中还观察到局限于特定国家的基因型（基因型III和X）。已结合已知抗原位点的氨基酸替换讨论了田间分离株的遗传多样性。这项工作为印度A 型FMDV的流行病学情况提供了有价值的见解，并为国家口蹄疫防控计划（如有需要）选择合适的疫苗株提供了必要信息。
