猪流感研究进展

猪流感是由正黏病毒科A型流感病 毒引起的猪的一种急性、传染性呼吸道疾病。 其特征为疾病突发,高热,精神沉郁,食欲废 绝,呼吸困难,阵发性咳嗽。猪流感病的病死 率不高,病猪可迅速康复。近年来,随着集约 化养猪规模的不断扩大,猪流感对养猪构成 了较大的威胁。此外,猪流感在人流感和禽 流感之间发挥着关键性作用,具有重大的公 共卫生意义,自1918年首次报道以来,猪流 感病一直受到人们的广泛关注。文章对猪流 感的病原、流行病学、诊断、防治、公共卫生意 义等方面作了概述。     

猪流感与猪感冒的临床鉴别及治疗

正冬季、晚秋时节都是猪群发生流感、感冒的高峰期,统称为感冒。猪流感、猪感冒属于同类疾病,但存在一定的差异性,猪流感主要通过种猪呼吸道进行传播,传染、多发是其显著特征,而猪感冒只是单一个体发病,并不是传染病。因此,本文作者客观阐述了猪流感与猪感冒的临床鉴别诊断,探讨了其治疗与预防。1猪流感与猪感冒的临床鉴别诊断1.1猪流感的临床鉴别诊断猪流感是由猪流感A型病毒引发的呼吸道传染病,具有     

甲型H1N1流感、猪流感与兽医公共卫生学的关系及其应对与防治

介绍了甲型H1N1流感、猪流感的流行与防治情况,阐述了其流行特点、病毒的基因组特性、流行病学特点、临床症状.提出了甲型H1N1流感与猪流感的诊断方法和防治措施以及高危人群的主要应对方法.并从兽医公共卫生学角度对其进行了探讨和思考.     

猪流感的再认识

猪流感是由流感病毒引起猪的急性呼吸道传染病。本文评述了猪流 进化、种间传播、公共卫生意义,认为猪流感在人流感和禽流感之间发挥着关键性作用,堪作研究人流感的动物模型和流感大流行的预警信号,建议重亲高猪流感。     

猪流感的诊断

据通报,墨西哥和美国近H相继发生人感染A／H1N1猪流感疫情。目前,世界卫生组织已进入高度戒备状态,总干事陈冯富珍表示,猪流感病毒有在全球广泛暴发的可能性,情况严重,须严密监控。为了搞好猪流感疫病防控,笔者从流行病学、临床学、微生物学等几方面论述了猪流感的诊断方法,以期能对猪流感的预防和诊断有所裨益。     

猪流感的诊断

据通报,墨西哥和美国近日相继发生人感染A/H1N1猪流感疫情.目前,世界卫生组织已进入高度戒备状态,总于事陈冯富珍表示,猪流感病毒有在全球广泛暴发的可能性,情况严重,须严密监控.为了搞好猪流感疫病防控,笔者从流行病学、临床学、微生物学等几方面论述了猪流感的诊断方法,以期能对猪流感的预防和诊断有所裨益.     

猪流感的发病趋势及防控措施

猪病毒性流感传染性较强,极易在猪场内大范围传播。猪流感会对猪的呼吸系统造成损伤,不但影响生长发育,而且也给公共卫生安全带来了一定的威胁。笔者对猪流感的发病情况、临床症状、诊断治疗方法和防控措施进行了深入研究。     

猪流感的监测及其公共卫生意义

猪流感（swine influenza,SI）是由猪流感病毒（swine influenza virus,SIV）引起的猪急性、高度接触传染性、群发性呼吸道疾病。临床以突发、高热、咳嗽、呼吸困难为特征,是目前危害养猪业的重要呼吸道疾病之一,给养猪业造成了巨大的经济损失。虽然流感病毒具有一定的宿主特异性,但越来越多的资料表明,猪作为流感病毒的＂混合器＂,在流感病毒跨种属障碍而感染新宿主的过程中起着重要的作用。因此,对猪流感的监测不仅对控制其发生和流行具有重要意义,而且其作为人流感的预警信号已引起各国的广泛关注,具有重要的公共卫生意义。     

猪流感的诊断与防治

正猪流感是一种由甲型流感病毒引起的急性呼吸道人畜共患传染病。猪流感病毒的传播速度非常快,猪流感在四季都可能发生,相对来说在气温变化较大的春季和冬季猪流感的发生率较高,猪流感一旦发作,病猪会通过打喷嚏、咳嗽等方式,将病毒排出体外,并由空气进行传播。因此,应当做好猪流感的诊断和防治工作,一旦发现猪流感必须第一时间进行隔离治疗。1猪流感的诊断猪流感是一种典型的猪传染疾病,对猪的健康构     

中国猪源HSN1和H9N2亚型流感病毒的分离鉴定

猪是禽流感病毒"禽-猪-人"传播链中重要的中间宿主,了解猪流感的疫情动态将为动物流感及人流感的疾病预测及防制提供重要依据.1999～2001年间进行的血清学和病毒学监测发现我国猪群存在大范围的H1和H3亚型猪流感感染(李海燕等,2002).2002～2003年,我们进一步对来自全国14个省市的1936份血清进行了H9亚型猪流感的检测,同时在广东、福建等省进行了H5亚型猪流感的检测.2002年辽宁、广东、山东及重庆猪血清中出现H9亚型流感抗体,阳性率分别为7.3%、6.8%、5.1%和1.6%.2003年采集的猪血清H9亚型流感抗体均为阴性,同时发现广东、福建两省2003年出现H5亚型流感阳性猪群,阳性率分别为4.7%和8.2%.从2001～2003年收集和送检的样品中分离鉴定了6株H9N2亚型和2株H5N1亚型猪流感病毒,部分序列分析发现H9和H5亚型猪流感病毒均与我国分离的禽流感病毒高度同源.本研究进一步确证了我国猪群中存在H9N2亚型流感病毒,并且首次发现我国猪群已出现H5N1亚型流感病毒,为人类流感及动物流感的防制敲响了警钟.对这两个亚型流感病毒所具有的公共卫生和兽医公共卫生危害性应予以高度重视.     

猪流感诊断技术研究进展

猪流感是由甲型流行性感冒病毒感染引起的一种急性呼吸道传染病。除常规的临床症状及病理变化诊断外,猪流感的确诊依赖于实验室诊断方法,方法主要有电镜技术、病毒分离和鉴定、血清学试验、免疫学试验、分子生物学方法等。作者从传统的实验室诊断技术和分子生物学诊断技术两个方面综合阐述了猪流感的诊断研究进展,为SIV的临床快速诊断和深入研究提供科学依据。     

猪流行性感冒

猪流感（Swine infl uenza,SI）是由猪流感病毒（Swine infl uenza virus,SIV）引起的一种猪的高度接触性、急性的具有传染性的群发性猪呼吸道疾病,该病毒属于正黏病毒科A型流感病毒属。该病的主要特征为突然发病、呼吸困难、咳嗽、发烧、疲劳倦怠及传播迅速、康复快、死亡率低。由于传播速度快、发病急,如果在一个发病初期治疗不及时,容易继发支气管炎、肺炎、胸膜炎、副猪嗜血杆菌感染等疾病,导致猪的死淘率增高,给养猪场户造成比较大的经济损失。文章将根据猪流感病毒的相关知识,从其病原学、临床症状等方面做出综述,并针对其特点讨论治疗及防控方法。     

The first detection of influenza in the Finnish pig population: a retrospective study

Background

Swine influenza is an infectious acute respiratory disease of pigs caused by influenza A virus. We investigated the time of entry of swine influenza into the Finnish pig population. We also describe the molecular detection of two types of influenza A (H1N1) viruses in porcine samples submitted in 2009 and 2010.This retrospective study was based on three categories of samples: blood samples collected for disease monitoring from pigs at major slaughterhouses from 2007 to 2009; blood samples from pigs in farms with a special health status taken in 2008 and 2009; and diagnostic blood samples from pigs in farms with clinical signs of respiratory disease in 2008 and 2009. The blood samples were tested for influenza A antibodies with an antibody ELISA. Positive samples were further analyzed for H1N1, H3N2, and H1N2 antibodies with a hemagglutination inhibition test. Diagnostic samples for virus detection were subjected to influenza A M-gene-specific real-time RT-PCR and to pandemic influenza A H1N1-specific real-time RT-PCR. Positive samples were further analyzed with RT-PCRs designed for this purpose, and the PCR products were sequenced and sequences analyzed phylogenetically.

Results

In the blood samples from pigs in special health class farms producing replacement animals and in diagnostic blood samples, the first serologically positive samples originated from the period July–August 2008. In samples collected for disease monitoring, < 0.1%, 0% and 16% were positive for antibodies against influenza A H1N1 in the HI test in 2007, 2008, and 2009, respectively. Swine influenza A virus of avian-like H1N1 was first detected in diagnostic samples in February 2009. In 2009 and 2010, the avian-like H1N1 virus was detected on 12 and two farms, respectively. The pandemic H1N1 virus (A(H1N1)pdm09) was detected on one pig farm in 2009 and on two farms in 2010.

Conclusions

Based on our study, swine influenza of avian-like H1N1 virus was introduced into the Finnish pig population in 2008 and A(H1N1)pdm09 virus in 2009. The source of avian-like H1N1 infection could not be determined. Cases of pandemic H1N1 in pigs coincided with the period when the A(H1N1)pdm09 virus was spread in humans in Finland.     

猪流感疫苗研究进展

猪流感是由猪流感病毒引起的一种急性高度传染性疾病,可引起病猪高热、食欲不振、呼吸困难、孕猪流产、延迟出栏等,同时该病常继发其他细菌病感染,严重危害养猪业的发展.由于该病具有重要的公共卫生意义,因此研制安全有效的疫苗尤其重要.目前对猪流感疫苗的研究热点主要集中在表位疫苗和利用反向遗传构建弱毒疫苗.论文针对国内外猪流感疫苗的研究情况做了系统描述,包括灭活疫苗、弱毒疫苗、DNA疫苗、载体疫苗等,旨在为新型疫苗的研制提供参考.     

猪流感病毒蛋白研究进展

猪流感（swine influenza,SI）是由猪流感病毒（swine influenza virus,SIV）引起的猪的一种传染病,其在世界各地的广泛存在和流行,给养猪业带来了巨大的经济损失。猪流感病毒属于正黏病毒科A型流感病毒属,作者就猪流感病毒蛋白,包括血凝素（HA）、神经氨酸酶（NA）、核蛋白（NP）、基质蛋白（M）、聚合酶蛋白（PA、PB1和PB2）和非结构蛋白（NS）进行简要概述,以期为猪流感病毒的致病机制、诊断、分子流行病学等方面的研究提供参考。     

Seroprevalence and risk factors for influenza A viruses in pigs in Peninsular Malaysia

Following a series of H5N1 cases in chickens and birds in a few states in Malaysia, there was much interest in the influenza A viruses subtypes that circulate among the local pig populations. Pigs may act as a mixing vessel for avian and mammal influenza viruses, resulting in new reassorted viruses. This study investigated the presence of antibodies against influenza H1N1 and H3N2 viruses in pigs from Peninsular Malaysia using Herdcheck Swine Influenza H1N1 and H3N2 Antibody Test Kits. At the same time, the presence of influenza virus was examined from the nasal swabs of seropositive pigs by virus isolation and real time RT-PCR. The list of pig farms was obtained from the headquarters of the Department of Veterinary Services, Malaysia, and pig herds were selected randomly from six of 11 states in Peninsular Malaysia. A total of 727 serum and nasal swab samples were collected from 4- to 6-month-old pigs between May and August 2005. By ELISA, the seroprevalences of swine influenza H1N1 and H3N2 among pigs were 12.2% and 12.1% respectively. Seropositivity for either of the virus subtypes was detected in less than half of the 41 sampled farms (41.4%). Combination of both subtypes was detected in 4% of all pigs and in 22% of sampled farms. However, no virus or viral nucleic acid was detected from nasal samples. This study identified that the seropositivity of pigs to H1N1 and H3N2 based on ELISA was significantly associated with factors such as size of farm, importation or purchase of pigs, proximity of farm to other pig farms and the presence of mammalian pets within the farm.     

基于SYBR Ⅰ实时荧光定量PCR对猪流行性腹泻病毒野毒和疫苗弱毒鉴别诊断方法的建立

本研究参考GenBank中登录的猪流行性腹泻病毒(Porcine epidemic diarrhea virus,PEDV)野毒株和弱毒疫苗株(CV777弱毒疫苗株)在高度保守ORF3基因核苷酸序列的差异,设计一对特异性荧光定量引物,分别建立基于SYBRⅠ实时荧光定量RT-PCR方法。结合熔解曲线分析可见,其野毒株和弱毒疫苗株熔解温度(Tm)分别为(81.84±0.17)℃和(83.16±0.14)℃,扩增产物的熔解曲线分析均只出现1个单特异峰,对传染性胃肠炎病毒、猪轮状病毒、猪细小病毒、猪流感病毒、猪繁殖与呼吸综合征病毒、猪伪狂犬病毒、猪瘟病毒均检测不到荧光信号。结合熔解曲线可直接鉴别猪群中PEDV的感染情况和程度,可对免疫猪群PEDV野毒感染和疫苗免疫做出快速准确的鉴别诊断,尤其是对PEDV弱毒疫苗免疫后仍爆发PEDV野毒感染的研究更有临床意义。     

Proinflammatory cytokines and viral respiratory disease in pigs

Swine influenza virus (SIV), porcine respiratory coronavirus (PRCV) and porcine reproductive and respiratory syndrome virus (PRRSV) are enzootic viruses causing pulmonary infections in pigs. The first part of this review concentrates on known clinical and pathogenetic features of these infections. SIV is a primary respiratory pathogen; PRCV and PRRSV, on the contrary, tend to cause subclinical infections if uncomplicated but they appear to be important contributors to multifactorial respiratory diseases. The exact mechanisms whereby these viruses cause symptoms and pathology, however, remain unresolved. Classical studies of pathogenesis have revealed different lung cell tropisms and replication kinetics for each of these viruses and they suggest the involvement of different lung inflammatory responses or mediators. The proinflammatory cytokines interferon-alpha (IFN-alpha), tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) have been shown to play key roles in several respiratory disease conditions. The biological effects of these cytokines and their involvement in human viral respiratory disease are discussed in the second part of this review. The third part summarises studies that were recently undertaken in the authors' laboratory to investigate the relationship between respiratory disease in pigs and bioactive lung lavage levels of IFN-alpha, TNF-alpha and IL-1 during single and combined infections with the above viruses. In single SIV infections, typical signs of swine "flu" were tightly correlated with an excessive and coordinate production of the 3 cytokines examined. PRCV or PRRSV infections, in contrast, were subclinical and did not induce production of all 3 cytokines. Combined infections with these 2 subclinical respiratory viruses failed to potentiate disease or cytokine production. After combined inoculation with PRCV followed by bacterial lipopolysaccharide, both clinical respiratory disease and TNF-alpha/IL-1 production were markedly more severe than those associated with the respective single inoculations. Taken together, these data are the first to demonstrate that proinflammatory cytokines can be important mediators of viral respiratory diseases in pigs.     

H1N1亚型猪流感病毒HA和NA基因双重RT-PCR定型检测方法的建立与应用

为了建立适用于临床诊断的H1N1亚型猪流感病毒快速检测方法,本研究根据GenBank已登录的H1N1亚型猪流感病毒HA和NA基因序列设计RT-PCR扩增引物,以H1N1亚型猪流感病毒、H3N2亚型猪流感病毒、猪瘟病毒和猪繁殖与呼吸综合征病毒为试验对照,通过优化RT-PCR反应条件和反应体系,建立了H1N1亚型猪流感病毒HA和NA基因双重RT-PCR定型检测方法。同时,运用H1N1亚型猪流感病毒血凝和血凝抑制试验方法和本研究建立的方法对165份猪病料样品进行了对比验证。结果表明,本研究建立的H1N1亚型猪流感病毒双重RT-PCR具有良好的特异性、敏感性、重复性,所扩增的目的基因片段大小分别为428 bp和678 bp左右,可检出最小基因组RNA浓度为2.9×10-5μg/μL。本研究建立的方法和H1N1亚型猪流感病毒血凝和血凝抑制试验方法均从同一份猪肺脏样品中检测出H1N1亚型猪流感病毒,其余样品中均未检出H1N1亚型猪流感病毒,两种方法符合率为100%。本研究建立的方法适用于H1N1亚型猪流感病毒双基因定型检测,可在H1N1亚型猪流感病毒流行病学调查和临床诊断中应用。