Jiménez de Oya Nereida, de Blas Ignacio, Blázquez Ana-Belén, Martín-Acebes Miguel A, Halaihel Nabil, Gironés Olivia, Saiz Juan-Carlos, Escribano-Romero Estela
Department of Biotechnology, INIA, Madrid, Spain.
BMC Res Notes. 2011 Oct 14;4:412. doi: 10.1186/1756-0500-4-412.
Hepatitis E virus (HEV) infection is a serious health problem in developing countries and is also increasingly reported in industrialized regions. HEV is considered a zoonotic agent and strains isolated from swine and human sources are genetically similar. Thus, HEV is of increasing importance to both public and animal health. The aim of the present study was to evaluate the distribution of HEV in a large population of pigs from herds located in different autonomous regions throughout Spain.
The presence of anti-HEV IgG antibodies was analyzed in 1141 swine serum samples (corresponding to 381 pigs younger than 6 months and 760 pigs older than 6 months) collected from 85 herds. Herds were located in 6 provinces in 4 autonomous regions throughout Spain. At least one pig tested positive for anti-HEV IgG in over 80% of herds. Of individual pigs, 20.4% (233/1141) were positive for anti-HEV IgG, with the prevalence being higher in adult pigs than in those under 6 months (30.2% vs. 15.5%). A subset of serum samples taken at 2- to 5-week intervals showed that seroprevalence dropped between 3 and 11 weeks of age, and then rose significantly by the 15th week. Pigs were also examined for the presence of HEV-RNA by RT-PCR. Of pigs tested for the presence of HEV-RNA 18.8% (64/341) were positive, with at least one pig in almost half of the herds testing positive. HEV-RNA amplicons from several positive pigs were sequenced and all were of genotype 3.
HEV was found to be widely distributed among swine farms across Spain, with the prevalence being highest among animals older than 6 months. These results indicate that HEV infection either is or is likely to become endemic in the Spanish swine population.
戊型肝炎病毒（HEV）感染在发展中国家是一个严重的健康问题，在工业化地区的报道也日益增多。HEV被认为是一种人畜共患病原体，从猪和人类来源分离出的毒株在基因上相似。因此，HEV对公共卫生和动物健康都越来越重要。本研究的目的是评估HEV在西班牙不同自治区大量猪群中的分布情况。
对从85个猪群收集的1141份猪血清样本（对应381头6个月以下的猪和760头6个月以上的猪）进行了抗HEV IgG抗体检测。这些猪群分布在西班牙4个自治区的6个省份。超过80%的猪群中至少有一头猪抗HEV IgG检测呈阳性。在个体猪中，20.4%（233/1141）抗HEV IgG呈阳性，成年猪的患病率高于6个月以下的猪（30.2%对15.5%）。每隔2至5周采集的一部分血清样本显示，血清阳性率在3至11周龄时下降，然后在第15周时显著上升。还通过逆转录聚合酶链反应（RT-PCR）检测猪是否存在HEV-RNA。在检测HEV-RNA的猪中，18.8%（64/341）呈阳性，几乎一半的猪群中至少有一头猪检测呈阳性。对几头阳性猪的HEV-RNA扩增子进行了测序，所有扩增子均为3型。
发现HEV在西班牙的猪场中广泛分布，6个月以上的动物患病率最高。这些结果表明，HEV感染在西班牙猪群中要么已经是地方病，要么很可能成为地方病。
