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1.
为了解河南地区猪戊型肝炎感染情况,同时掌握该地区猪感染戊型肝炎病毒的基因型,对来自河南新乡、平顶山、南阳等地区不同商品猪场血清、肝脏、粪样品,采用ELISA技术检测猪血清中抗HEV特异性抗体水平,并使用套式RT-PCR检测肝脏和粪便中猪戊型肝炎病毒核酸。结果显示530份样品中HEV抗体阳性率0.6%,HEV RNA均为阴性,推测目前河南省猪戊型肝炎病毒感染率较低。  相似文献   

2.
Genotype 3 hepatitis E has been widespread in pig farms of Shanghai suburbs   总被引:1,自引:0,他引:1  
Ning H  Yu S  Zhu Y  Dong S  Yu R  Shen S  Niu Z  Li Z 《Veterinary microbiology》2008,126(1-3):257-263
Hepatitis E virus (HEV) genotype 3 was first identified in swine raised on a Shanghai suburban pig farm in late 2006. To accurately determine the prevalence of HEV infections among Shanghai pig farms, 426 pig fecal samples were collected from 37 pig farms located in all 10 Shanghai suburban districts and tested for the presence of HEV RNA using RT-PCR. Genetic analysis based on an amplified 150-bp ORF2 fragment revealed 111 samples to be HEV positive, and the prevalence of HEV infection within the different districts varied between 0 and 41.7%. Thirty-two samples were sequenced, and phylogenetic analysis indicated that 10 isolates belonged to HEV genotype 4 and were most closely related to 3 human and 2 swine HEV strains, all of which had originally been isolated from Asian countries including Japan and China. The remaining 22 isolates belonged to genotype 3 and were most closely related to a strain of swine HEV, US-SW, isolated from pigs in the United States. Our data indicated that genotype 3 HEV was widespread among suburban Shanghai pig farms although further study is required to determine the source and zoonotic nature of the virus.  相似文献   

3.
部分猪场H1和H3亚型猪流感的血清学调查   总被引:1,自引:0,他引:1  
为了解中国部分省市规模化猪场H1和H3亚型猪流感病毒的流行情况,采用血凝抑制试验对采集于广东、湖南、河南省12个市县28个规模化猪场的799份血清进行H1和H3亚型猪流感病毒的抗体检测。结果表明,H1亚型抗体阳性率在0~83.33%之间,猪抗体总阳性率为46.18%(369/799),猪场阳性率为89.29%(25/28)。H3亚型抗体阳性率在0~100.00%之间,猪抗体总阳性率为61.33%(490/799),猪场阳性率为85.71%(24/28)。广东、湖南和河南地区H1亚型抗体阳性率分别为48.91%、40.26%和50.67%,H3亚型抗体阳性率分别为58.55%、70.78%和78.67%。在被调查的上述3个地区的猪群中,H1和H3亚型猪流感病毒的感染较为普遍,其中H3亚型感染率高于H1亚型,且各地区猪流感病毒的流行情况存在地域性差异。  相似文献   

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6.
This study describes the distribution of Hepatitis E virus (HEV) in a naturally infected swine population and the genetic relatedness of HEV strains on swine farms in Spain. Of fecal and serum samples collected from 131 pigs and manure-ditch samples collected from 17 farms, HEV was detected in 16%, 14%, and 59%, respectively, for an overall prevalence rate of 23%. The maximum prevalence rates for feces and serum were in pigs 5 to 12 wk old. A high prevalence of the virus in feces (18%) was observed in sows. Gene sequencing was performed on 6 strains from feces, serum, and manure ditch: the nucleotide identities varied from 81.5% to 99% when compared with those of other strains of genotype 3 isolated from swine. This is the first study in Europe to show the variation in virus distribution by age in feces and serum in a naturally infected swine population.  相似文献   

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8.
Hepatitis E is a zoonotic disease and is highly prevalent in European swine livestock. There is a need to compare the infection dynamics of hepatitis E virus (HEV) between herds with the same production system and determine the percentage of animals that could arrive infected at slaughter age. Therefore, a longitudinal study was performed in six Spanish farrow-to-finish affected farms. Twenty piglets per farm were monitored from nursery to slaughter. RT-PCR and serology techniques were applied to analyze longitudinally collected sera and/or faecal samples. Liver and bile samples were also taken at the abattoir. Anti-HEV IgM were firstly detected at 7 weeks of age in 5 farms whereas at 13 weeks of age in 1 farm (farm 2). At slaughter age 50–100% of pigs had seroconverted to anti-HEV IgG in the former 5 farms whereas in the other herd only 5% of pigs were IgG seropositive (farm 2). Six out of 96 livers and 5 out of 80 biles analyzed were HEV positive at the abattoir (total percentage of infected animals: 11.5%). All these positive animals had already seroconverted except 2 pigs of farm 2. Hence, pigs can be seronegative at slaughter age being infected during the latest fattening period. Manipulation of HEV-infected livers or other organs from pigs could be considered a possible route of transmission in Spanish abattoirs. This study represents the first longitudinal survey on swine HEV infection dynamics conducted in different herds.  相似文献   

9.
为了解广西猪群中戊型肝炎病毒(HEV)基因型,利用套式RT-PCR用对南宁周边猪场采集到的104份新鲜猪粪便进行HEV检测、分离并成功扩增和克隆了11株阳性毒株的ORF2基因部分保守片段.序列测定结果表明,11株HEV ORF2序列自身核苷酸同源性为97.7%~100%,推导编码的氨基酸同源性为97.9%~100%;与4型HEV代表毒株Ch-S-1、Ch-T11、swGX40等的核苷酸同源性为84.6%~90.6%,而与其他各型之间的同源性较低.系统发育进化树结果表明,11株HEV广西株为基因4型,其中,10株HEV为4a亚型,1株毒株为4e亚型.结果表明,广西猪群中流行的HEV均为基因4型,且以4a亚型为优势流行毒株.  相似文献   

10.
旨在调查四川地区藏猪戊型肝炎病毒(hepatitis E virus,HEV)的流行情况和遗传演化,作者用RT-PCR法对2018—2020年采集自四川省甘孜藏族自治州和阿坝藏族自治州的22个藏猪场332份藏猪粪便样本进行HEV检测,并对阳性样本进行基因分型。RT-PCR检测结果表明HEV核酸阳性率为20.48%(68/332,95% CI=16.3%~25.2%),22个规模藏猪场中HEV猪场阳性率为77.27%(17/22,95% CI=54.6%~92.2%),健康样本阳性率为2.86%(3/105,95% CI=0.6%~8.1%),腹泻样本阳性率为28.63%(65/227,95% CI=22.8%~35.0%),系统进化分析显示所有阳性株均为G4型。为了进一步研究该地区流行毒株的演化过程,以贝叶斯进化分析软件进行分歧时间估算,结果表明,藏猪流行毒株的分歧时间最早为1999年,最晚为2016年。并分别从每年的样本中挑选1份阳性样本得到全基因组序列,核酸序列相似性为89.5%~93.1%。通过对3条全基因组重组分析发现SWU/301/2019存在重组现象,SWU/301/2019重组区域位于ORF1的3 746—4 655 bp。本研究首次对四川地区藏猪源HEV进行调查,结果表明四川藏猪中存在一定程度的HEV感染,为四川地区对藏猪感染HEV的防治以及深入研究四川藏猪源HEV遗传变异及生物学特性提供了参考依据。  相似文献   

11.
Borrelia burgdorferi sensu stricto is the main etiological agent of Lyme disease (LD) in the USA. In Brazil, it is believed that a similar spirochete is the causal agent of the Baggio–Yoshinari syndrome (BYS), a zoonosis also transmitted by ticks, whose clinical manifestations are similar to those of LD. Despite the epidemiological importance, there are no studies reporting the presence and the prevalence of B. burgdorferi among horses in Mato Grosso State. The aim of this study was to detect and measure the frequency of IgG antibodies anti-B. burgdorferi American strain G39/40 in horses in the municipality of Sinop, MT—Brazil, using the indirect enzyme-linked immunosorbent assay (ELISA) for serological diagnosis. Blood samples from 367 horses were collected in 81 farms. An epidemiological questionnaire was applied during the visits to obtain information related to the animals and the farms. From the 367 horses, 214 were positive for B. burgdorferi sensu stricto according to the results of the ELISA test, representing an apparent prevalence of 54.04% [CI?=?0.4548051–0.6237234]. Concomitantly, 89 blood samples were taken for molecular analysis by nested polymerase chain reaction (PCR). According to the PCR test results, none of the samples were reactive, although 53 of these samples were reactive according to ELISA. Seventy five farms (92.59%) had at least one reactive horse for B. burgdorferi. Our results support the hypothesis of the presence of anti-Borrelia spp. antibodies in horses in Mato Grosso, reaching a high animal prevalence. Besides that, leisure/sport purposes proved to be a risk factor, with an odds ratio of 3.16. These findings clearly indicate the need of borreliosis control in Sinop and make a significant contribution to the knowledge of the disease in Mato Grosso.  相似文献   

12.
The aim of this study was to determine at which production stages hepatitis E virus (HEV) is shed by the highest number of pigs and to estimate the relative risk associated with each stage. For this purpose, 146 fecal samples of pigs from 21 farms were studied. In addition, 1 sample from the manure ditch and another sample of drinking water, collected directly from the trough located in the pen, were taken from 16 farms. HEV RNA was detected in fecal samples from 34 pigs (23.29%). The production stages in which most pigs excreted HEV were weaners (41.7%) and pigs in the first month of feeding (60%). The results of the statistical analysis showed that the principal significant risk stage in HEV shedding was the first month of feeding (odds ratio [OR] 19.5, 95% CI 3.59-106.07, P = 0.001) followed by the weaners stage (OR 9.3, 95% CI .78-48.42, P = 0.008). In 8 out of 16 farms tested (50%) HEV RNA was detected in raw manure and in the water trough of only 1. Detection of HEV in manure ditches raises the concern of how to deal with manure of swine origin, because it is used as soil fertilizer.  相似文献   

13.
In the United Kingdom, there has been an increase in the number of hepatitis E virus (HEV) infections in people annually since 2010. Most of these are thought to be indigenously acquired Orthohepevirus A genotype 3 (HEV G3), which has been linked to pork production and consumption. However, the dominant subgroup circulating in British pigs differs from that which is found in people; therefore, an alternative, potentially zoonotic, source is suspected as a possible cause of these infections. Rodents, brown rats (Rattus norvegicus) in particular, have been shown to carry HEV, both the swine HEV G3 genotype and Orthohepevirus C, genotype C1 (rat HEV). To investigate the prevalence of HEV in British rodents, liver tissue was taken from 307 rodents collected from pig farms (n = 12) and other locations (n = 10). The RNA from these samples was extracted and tested using a pan‐HEV nested RT‐PCR. Limited histopathology was also performed. In this study, 8/61 (13%, 95% CI, 5–21) of brown rat livers were positive for HEV RNA. Sequencing of amplicons demonstrated all infections to be rat HEV with 87%–92% nucleotide identity to other rat HEV sequences circulating within Europe and China (224 nt ORF‐1). Lesions and necrosis were observed histologically in 2/3 samples examined. No rat HEV RNA was detected in any other species, and no HEV G3 RNA was detected in any rodent in this study. This is the first reported detection of rat HEV in Great Britain. A human case of rat HEV infection has recently been reported in Asia, suggesting that rat HEV could pose a risk to public health.  相似文献   

14.

Background

Hepatitis E virus (HEV) is a zoonotic pathogen of which swine was reported as major reservoirs. HEV has been divided into 4 different genotypes according to phylogenetic analysis. Recent reports showed that genotype 4 HEV is freely transmitted between humans and swine in eastern China, including Shanghai area. This paper investigated the recent infection status of HEV among swine population of Shanghai area in China.

Methods

480 swine faecal specimens were collected from 23 farms which distribute all over Shanghai from September to November, 2007 and tested for the presence of HEV RNA by the polymerase chain reaction (PCR).

Results

Our results showed that 26.1% (6/23) of the swine farms were positive for HEV RNA and the positive rate of the six farms were ranged from 9.1% to 33.3%. The HEV RNA positive rate for total samples were 5% (24/480). The resulted positive band specific for HEV was sequenced and sequence analysis indicated that all of these isolates belonged to genotype 4 HEV. Phylogenetic analysis showed that the 24 isolates clustered into 4 distinct subgroups, sharing 83.3–89.7% inter-subgroup and 97–99% intra-subgroup identities. More over, isolates in three of the four subgroups closely clustered with previous identified strains, sharing up high to 97% identity with them.

Conclusion

These results suggested that there were 4 different subgenotypes of HEV prevalent in Shanghai, and some of them may not be indigenous to Shanghai but introduced from other geographic regions.  相似文献   

15.
Surveillance of hepatitis E virus (HEV) in risk groups is an important strategy to monitor its circulation pattern and to timely detect changes thereof. The aims of this cross-sectional study were to estimate the prevalence of HEV infections in pigs and humans from different regions of the country, to identify risk factors for increasing anti-HEV IgG prevalence and to characterize HEV strains. The presence of anti-HEV antibodies was assessed by commercial ELISA in serum samples from the general population, farm and slaughterhouse employees, as well as pigs sampled in the three regions of Cuba from February to September 2016. Overall, individuals with occupational exposure to swine or swine products (70/248, 28.2%) were 4 times more likely to be seropositive compared to the general population (25/285, 8.7%; OR: 4.18; p < .001). Within the risk group, risk factors included age, number of years working in a professional activity with direct exposure to swine, geographic region and distance between residence and closest professional swine setting, while wearing gloves had a protective effect. Prevalence of total anti-HEV antibodies in swine was 88.2% (165/187) and HEV RNA was detected by real-time RT-PCR in 9.2% (16/173) swine stools. All HEV strains sequenced clustered within genotype 3. Some strains clearly belonged to subtype 3a, while another group of strains was related with subtypes 3b and 3 k but partial HEV sequences did not allow unequivocal subtype assignment. These findings suggest that the high HEV exposure in Cuban individuals with swine-related occupations could be due to enzootic HEV in certain regions, direct contact with infectious animals or their products as well as environmental contamination.  相似文献   

16.
Li W  She R  Wei H  Zhao J  Wang Y  Sun Q  Zhang Y  Wang D  Li R 《Veterinary microbiology》2009,133(1-2):75-83
This study was to investigate the prevalence of HEV in pig herds under different breeding environment and in abattoirs located in Beijing, China. In total 638 sera samples and 114 liver samples were collected for a serological survey and a RT-PCR assay, respectively. The average prevalence rate of HEV in pig herds in Beijing suburb were 47.5-100%. Seropositive rate was 76.6% for pig herds of large-scale and 90% for family-scale farms. For sera samples collected from abattoir, 127 samples (78.4%) were found to be positive. Among four liver samples (3.5%) that positive for HEV RNA detection, two strains of HEV has been identified. the two detected HEV sequences shared 99.1% nucleotide sequence identity with each other, and 76.4-81.0%, 76.5-76.8%, 75.7-79.0% and 85.2-96.4% with related strains representing genotype 1, 2, 3, and 4, respectively. Further phylogenetic analysis revealed two HEV sequences belonged to genotype 4 and exhibited a high identity with strain JKO-ChiSai98C (95.4 and 95.7%), and with strains 87, 277 and 292 (96.1-96.4%) isolated from patients with sporadic acute hepatitis E in Beijing, China. The results of this study indicated that the prevalence of HEV in the pig herds were quite high. Additional public-health concerns might be placed on pork safety.  相似文献   

17.
猪血凝性脑脊髓炎病毒的血清学调查   总被引:1,自引:0,他引:1  
应用血凝和血凝抑制试验检测了从辽宁省部分地区采集的猪血清中血凝性脑脊髓炎病毒(HEV)的抗体滴度。结果表明,368份血清样品中,有162份呈抗体阳性反应,阳性率高达44.0%。被采集血清的猪未表现出临床症状,说明该地区存在血凝性脑脊髓炎病毒的隐性感染。  相似文献   

18.
结合化验室每年的监测工作,从2007年~2009年,对凉州区辖区内的95个规模养殖场和41个散养户的1 342份猪血清进行了猪瘟疫苗免疫抗体的监测,监测结果显示,凉州区猪瘟防制成效显著,猪瘟疫苗免疫抗体水平有逐年提高的趋势,规模养殖户猪瘟疫苗免疫抗体水平高于散养户,免疫注射2次所产生的抗体效价明显高于免疫1次的,抗体监测工作的开展,对淘汰亚临床感染猪,考核免疫效果,制定科学合理的免疫程序提供了科学的依据,有效防止猪瘟的发生,为凉州区养猪业的稳定发展发挥了积极作用。  相似文献   

19.
Hepatitis E virus (HEV) is currently considered as a global health concern due to the recognition of its zoonotic transmission to humans, mainly from swine, and its association with the development of severe cases of hepatitis in human risk populations. The lack of updated data on HEV state of infection in swineherds of Argentina, and the necessity of robust technologies for its detection in complex biological samples, positions HEV as an emerging issue in public health. Here, we have optimized a RT‐qPCR with internal control for a more precise and accurate HEV RNA detection in swine stool samples. We implemented this optimized molecular tool to analyse the current epidemiological scenario of HEV infection in swine from the core region of commercial activity of Argentina. A total of 135 stool samples were collected from 16 different farms and tested for HEV presence, resulting in 11 positive cases (8.1%). Phylogenetic analysis demonstrated that all of them correspond to HEV genotype 3 and that different subtypes circulate in the region. Moreover, two of the detected strains presented a high nucleotide similarity with a previously identified isolate from human sewage discharges, suggesting the zoonotic transmission of HEV to humans. Collectively, this work provides a better understanding of HEV epidemiology in Argentina while contributes to the improvement of HEV detection technologies.  相似文献   

20.
Hepatitis E is an infectious disease which virus (HEV) is highly disseminated in swine herd populations. Sporadic acute human hepatitis E cases have been associated to genotype 3 and 4 strains of HEV also reported in swine populations of endemic and non-endemic areas. With the aim to evaluate the incidence of animals with current infection of HEV, 115 bile samples were collected from three slaughterhouses under inspection by Animal Sanitary Protection Agency of Rio de Janeiro, Brazil. In parallel, effluent samples were collected from six sewage pipe exit sites of two slaughterhouses. HEV RNA was detected in 11 out of 115 (9.6%) bile samples collected and three waste samples from one slaughterhouse. Viral loads observed for bile samples varied from 10(1)-10(5) genome copies/mL and for effluent samples mean load was 10(2) genome copies/mL. Sequencing and phylogenetic analysis classified samples within genotype 3 subtype 3b closely related to the sample obtained from the first reported autochthonous human case and samples from swine of commercial herds in Brazil. Our data demonstrates that although most animals achieve slaughter age (around 20 weeks old) already immune to HEV, a significant number of animals are with current infection at commercial age. Further studies should be addressed to consider risk analysis and possible evaluation of inspection regulations considering food safety measures regarding hepatitis E zoonotic aspect in Brazil.  相似文献   

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