Department of Microbiology and Immunology, Faculty of Veterinary Medicine, Kasetsart University, 50 Paholyothin Road, Chatuchak, Bangkok, 10900, Thailand; Interdisciplinary Graduate Program in Genetic Engineering, Kasetsart University, 50 Paholyothin Road, Chatuchak, Bangkok, 10900, Thailand.
Vet Microbiol. 2013 Dec 27;167(3-4):314-26. doi: 10.1016/j.vetmic.2013.09.007. Epub 2013 Sep 13.
Swine influenza virus (SIV) is one of the most important zoonotic agents and the origin of the most recent pandemic virus. Asia is considered to be the epicenter for genetic exchanging of influenza A viruses and Southeast Asia including Thailand serves as a reservoir to maintain the persistence of the viruses for seeding other regions. Therefore, searching for new reassortants in this area has been routinely required. Although SIVs in Thailand have been characterized, collective information regarding their genetic evolution and gene constellations is limited. In this study, whole genomes of 30 SIVs isolated during clinical target surveillance plus all available sequences of past and currently circulating Thai SIVs were genetically characterized based on their evolutionary relationships. All genetic pools of Thai SIVs are comprised of four lineages including classical swine (CS), Eurasian swine (EAs), Triple reassortants (TRIG) and Seasonal human (Shs). Out of 84 isolates, nine H1N1, six H3N2 and one H1N2 strains were identified. Gene constellations of SIVs in Thailand are highly complex resulting from multiple reassortments among concurrently circulating SIVs and temporally introduced foreign genes. Most strains contain gene segments from both EAs and CS lineages and appeared transiently. TRIG lineage has been recently introduced into Thai SIV gene pools. The existence of EAs and TRIG lineages in this region may increase rates of genetic exchange and diversity while Southeast Asia is a persistent reservoir for influenza A viruses. Continual monitoring of SIV evolution in this region is crucial in searching for the next potential pandemic viruses.
猪流感病毒（SIV）是最重要的人畜共患病原体之一，也是最近大流行病毒的起源。亚洲被认为是流感 A 病毒基因交换的中心，包括泰国在内的东南亚地区是维持病毒持续存在并向其他地区传播的储存库。因此，该地区需要经常寻找新的重组病毒。尽管泰国的 SIV 已经得到了特征描述，但关于其遗传进化和基因组合的综合信息有限。在这项研究中，基于进化关系，对 30 株在临床目标监测中分离的 SIV 以及过去和当前流行的所有泰国 SIV 序列的全基因组进行了遗传特征分析。泰国 SIV 的所有遗传群都由四个谱系组成，包括经典猪流感（CS）、欧亚猪流感（EAs）、三重重组（TRIG）和季节性人源（Shs）。在 84 株分离株中，鉴定出 9 株 H1N1、6 株 H3N2 和 1 株 H1N2 株。泰国 SIV 的基因组合非常复杂，是由同时流行的 SIV 和暂时引入的外源基因之间的多次重组造成的。大多数菌株包含来自 EAs 和 CS 谱系的基因片段，并且只出现过短暂时间。TRIG 谱系最近被引入到泰国 SIV 基因库中。该地区 EAs 和 TRIG 谱系的存在可能会增加遗传交换和多样性的速度，而东南亚地区是流感 A 病毒的持续储存库。持续监测该地区 SIV 的进化对于寻找下一个潜在的大流行病毒至关重要。
