Department of Pain Management, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jingwu Road, Jinan, Shandong Province, 250021, China.
Department of Epidemiology and Biostatistics, University of Georgia, GA 30602, USA.
Vet Microbiol. 2017 Nov;211:174-179. doi: 10.1016/j.vetmic.2017.10.016. Epub 2017 Oct 18.
Swine influenza A virus (IAV) can cause widespread respiratory disease with high morbidity, low mortality, and have a substantial economic impact to the swine industry. Swine infection may contribute to pandemic IAV given their susceptibility to both avian and human IAVs. Currently, three IAV subtypes (H1N1, H3N2 and H1N2) circulate in swine in North America frequently combining gene segments from avian or human viruses. This study investigated the prevalence of IAV in commercial swine herds. A total of 1878 oral fluid samples were collected from pigs of all ages from 201 commercial farms located in North Carolina and South Carolina. Sixty-eight oral fluid samples from 35 farms were positive by MP gene PCR with an overall IAV-positivity of 3.6%. On the herd level, the percentage of IAV positivity was 17.4%. Fifty-six viruses were subtyped, while 12 were partly subtyped or not subtyped at all. Using de novo assembly, complete sequences were obtained for 59 HA genes. The majority of IAVs subtyped had an H1 HA demonstrating a considerable prevalence over H3 viruses. Furthermore, only six out of eleven HA types were detected which has implications for the selection of vaccines used by swine producers in the region.
猪流感病毒（IAV）可引起广泛的呼吸道疾病，发病率高，死亡率低，对养猪业有重大的经济影响。猪感染可能会导致 IAV 大流行，因为它们易感染禽源和人流感病毒。目前，三种 IAV 亚型（H1N1、H3N2 和 H1N2）在北美猪群中频繁流行，它们结合了禽源或人流感病毒的基因片段。本研究调查了商业猪群中 IAV 的流行情况。从北卡罗来纳州和南卡罗来纳州的 201 个商业农场采集了所有年龄段猪的 1878 份口腔液样本。35 个农场的 68 份口腔液样本通过 MP 基因 PCR 呈阳性，IAV 阳性率总体为 3.6%。在畜群水平上，IAV 阳性率为 17.4%。对 56 种病毒进行了亚型分析，其中 12 种病毒部分亚型或未完全亚型。通过从头组装，获得了 59 个 HA 基因的完整序列。大多数分型的 IAV 具有 H1 HA，表明其在 H3 病毒中具有相当高的流行率。此外，只检测到 11 种 HA 类型中的 6 种，这对该地区养猪户使用的疫苗选择有影响。
