Houston Elizabeth, Giménez-Lirola Luis Gabriel, Magtoto Ronaldo, Mora-Díaz Juan Carlos, Baum David, Piñeyro Pablo Enrique
Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
Prev Vet Med. 2019 Apr 1;165:1-7. doi: 10.1016/j.prevetmed.2019.01.012. Epub 2019 Jan 29.
Senecavirus A (SVA) is a single-stranded RNA virus in the family Picornaviridae. Recently, SVA has been associated with idiopathic vesicular disease and increased neonate mortality outbreaks in the United States, Brazil, China, Colombia, and Thailand, with increasing incidence since 2014. Indirect detection by antibody detection methods, including indirect immunofluorescence assay (IFA), virus neutralization assay, and competitive or indirect enzyme-linked immunosorbent assays (ELISAs), have been reported in clinical and experimental trials. The objective of this study was to determine the seroprevalence of SVA in nonclinical affected herds in the United States. Individual samples were collected from 3654 and 2433 clinically healthy grower-finisher pigs and sows, respectively, from 219 unique commercial swine production sites. SVA seroprevalence was evaluated by SVA rVP1 ELISA and SVA IFA. The estimated seroprevalence for grower-finisher pigs and sows was 12.2% and 34.0%, respectively. The herd prevalence was 42.7% for grower-finisher farms and 75.8% for sow farms. The SVA rVP1 ELISA and SVA IFA exhibited a fair (sows) and moderate (grower-finisher) agreement at the herd level, while a fair agreement was observed at the individual level for both pig categories evaluated. The McNemar's test was significant at the individual and herd level (p < 0.05). In this study, we demonstrated the presence of SVA IgG antibodies in pigs from clinically healthy grower-finisher and sow herds. These results suggest that SVA is circulating subclinically in sow farms and grower-finisher pig farms in major swine producing-states in the United States.
A群猪肠道病毒（SVA）是小RNA病毒科的一种单链RNA病毒。最近，SVA与美国、巴西、中国、哥伦比亚和泰国的特发性水疱病以及新生儿死亡率增加的疫情有关，自2014年以来发病率不断上升。在临床和实验研究中，已经报道了通过抗体检测方法进行间接检测，包括间接免疫荧光测定法（IFA）、病毒中和试验以及竞争性或间接酶联免疫吸附测定法（ELISA）。本研究的目的是确定美国未受临床影响猪群中SVA的血清流行率。分别从219个独特的商业养猪场采集了3654头临床健康的生长育肥猪和2433头母猪的个体样本。通过SVA重组病毒蛋白1（rVP1）ELISA和SVA IFA评估SVA血清流行率。生长育肥猪和母猪的估计血清流行率分别为12.2%和34.0%。生长育肥猪场的群体流行率为42.7%，母猪场为75.8%。SVA rVP1 ELISA和SVA IFA在群体水平上对母猪表现出一般一致性，对生长育肥猪表现出中等一致性，而在个体水平上，对所评估的两类猪均观察到一般一致性。McNemar检验在个体和群体水平上均具有显著性（p < 0.05）。在本研究中，我们证明了临床健康的生长育肥猪群和母猪群中的猪存在SVA IgG抗体。这些结果表明，SVA在美国主要养猪州的母猪场和生长育肥猪场中呈亚临床传播。
