关键词： Influenza virus   Virus–host interactions  

摘要： Zoonotic influenza A viruses of avian origin can cause severe disease in individuals, or even global pandemics, and thus pose a threat to human populations. Waterfowl and shorebirds are believed to be the reservoir for all influenza A viruses, but this has recently been challenged by the identification of novel influenza A viruses in bats(1,2). The major bat influenza A virus envelope glycoprotein, haemagglutinin, does not bind the canonical influenza A virus receptor, sialic acid or any other glycan(1,3,4), despite its high sequence and structural homology with conventional haemagglutinins. This functionally uncharacterized plasticity of the bat influenza A virus haemagglutinin means the tropism and zoonotic potential of these viruses has not been fully determined. Here we show, using transcriptomic profiling of susceptible versus non-susceptible cells in combination with genome-wide CRISPR-Cas9 screening, that the major histocompatibility complex class II (MHC-II) human leukocyte antigen DR isotype (HLA-DR) is an essential entry determinant for bat influenza A viruses. Genetic ablation of the HLA-DR alpha a-chain rendered cells resistant to infection by bat influenza A virus, whereas ectopic expression of the HLA-DR complex in non-susceptible cells conferred susceptibility. Expression of MHC-II from different bat species, pigs, mice or chickens also conferred susceptibility to infection. Notably, the infection of mice with bat influenza A virus resulted in robust virus replication in the upper respiratory tract, whereas mice deficient for MHC-II were resistant. Collectively, our data identify MHC-II as a crucial entry mediator for bat influenza A viruses in multiple species, which permits a broad vertebrate tropism.

关键词： 桂越边境地区   蝙蝠   病毒宏基因组学   遗传多样性  

摘要： 桂越地区包括越南和我国广西,地理位置的战略意义突出,该地区蝙蝠资源丰富,且越南境内的蝙蝠携带多种人兽共患病毒.为了监测桂越边境地区蝙蝠病毒的跨境传播,防范蝙蝠病毒引发新发传染病,掌握该地区蝙蝠携带病毒的病原本底和重要病毒遗传进化特征具有重要意义.本研究在桂越边境采集蝙蝠样本并对其进行病毒宏基因组学分析,结果发现了49个科的病毒,包括脊椎动物病毒、植物病毒、昆虫病毒和噬菌体.根据病毒宏基因组学结果,对注释到的嗜肝DNA病毒、博卡细小病毒、A型轮状病毒、星状病毒、弹状病毒和冠状病毒进行检测和进化分析,结果发现星状病毒广泛分布,且具有丰富的遗传多样性;其他病毒则呈局部分布,其中嗜肝DNA病毒、冠状病毒、轮状病毒与各自参考毒株进化关系较近,为这些病毒的变异毒株;而博卡细小病毒和弹状病毒与已知病毒具有很明显的遗传差异性,可能为病毒新种;值得注意的是,发现的蝙蝠轮状病毒与广西当地人轮状病毒具有很高的同源性,提示该病毒的跨种传播和基因重排.本研究获得了桂越边境地区蝙蝠携带病毒的本底数据以及部分重要病毒在该地区蝙蝠中的流行情况和遗传进化特征,为监测蝙蝠病毒的跨境传播、防范新发病毒病提供了重要的基础数据.

关键词： 蝙蝠   轮状病毒   进化分析  

摘要： 为监测东南沿海舟山地区蝙蝠携带轮状病毒的流行情况,探索其流行机制,2015—2018年,在浙江省舟山地区采集蝙蝠,以蝙蝠肠组织为模板,设计针对轮状病毒VP3序列的特异引物进行RT-PCR检测。结果显示,2015年采集的65只蝙蝠,轮状病毒阳性率为6.15%(4/65),2016年采集的48只蝙蝠,阳性率为2.08%(1/48),2017年采集的70只蝙蝠,阳性率为2.86%(2/70),而2018年采集的101只蝙蝠,未检测到轮状病毒序列。针对2017年小菲菊头蝠Rhinolophus hipposideros体内发现的一株轮状病毒进行基因组扩增,获取部分基因组序列并进行生物信息学分析,发现VP7基因序列与蝙蝠源轮状病毒相似度最高,同源性为96%;VP3基因序列与人源轮状病毒同源性为90%;VP6基因序列与猫同源性为95%。根据上述结果,我们推测舟山蝙蝠来源轮状病毒是一株重组病毒株,具有潜在跨种传播给人类的可能性。本研究系首次在东南沿海舟山地区蝙蝠体内检测到轮状病毒,对该地区轮状病毒的监测和预警具有一定的公共卫生意义。

关键词： 高通量测序   细小病毒   蝙蝠   核酸检测  

摘要： 为了研究中国东南沿海地区蝙蝠作为媒介和宿主携带重要人兽共患病毒的种类及分布情况,分析蝙蝠传播病毒的可能性,从东南沿海地区多个采样点采集了一定数量的成年蝙蝠样本,取部分肠道组织样本进行处理后,用高通量测序和生物信息学对其携带病毒的核酸序列进行了提取和分析。结果显示,蝙蝠携带多种昆虫病毒、植物病毒和脊椎动物病毒,其中细小病毒读长占比最多,15 012个病毒读长中有12 894个是细小病毒序列。针对高通量测序结果,对蝙蝠携带的细小病毒进行了鉴定与分析,并获取了大部分编码区基因,同源比对发现与BtRf-PV病毒株和SX2013株同源性最高,为91%。在采集的268只蝙蝠中,检测到16只携带细小病毒,阳性率为5.9%。

关键词： bats   genetic conflict   HBV   hepadnavirus   NTCP   positive selection   primates   receptor   rodents   virus-host interactions  

摘要： Human hepatitis B virus (HBV) is a global health problem, affecting more than 250 million people worldwide. HBV-like viruses, named orthohepadnaviruses, also naturally infect nonhuman primates, rodents, and bats, but their pathogenicity and evolutionary history are unclear. Here, we determined the evolutionary history of the HBV receptors NTCP and GPC5 over millions of years of primate, rodent, and bat evolution. We use this as a proxy to understand the pathogenicity of orthohepadnaviruses in mammalian hosts and to determine the implications for species specificity. We found that NTCP, but not GPC5, has evolved under positive selection in primates (27 species), rodents (18 species), and bats (21 species) although at distinct residues. Notably, the positively selected codons map to the HBV-binding sites in primate NTCP, suggesting past genetic " arms races" with pathogenic orthohepadna-viruses. In rodents, the positively selected codons fall outside and within the presumed HBV-binding sites, which may contribute to the restricted circulation of rodent orthohepadnaviruses. In contrast, the presumed HBV-binding motifs in bat NTCP are conserved, and none of the positively selected codons map to this region. This suggests that orthohepadnaviruses may bind to different surfaces in bat NTCP. Alternatively, the patterns may reflect adaptive changes associated with metabolism rather than pathogens. Overall, our findings further point to NTCP as a naturally occurring genetic barrier for cross-species transmissions in primates, which may contribute to the narrow host range of HBV. In contrast, this constraint seems less important in bats, which may correspond to greater orthohepadnavirus circulation and diversity. IMPORTANCE Chronic infection with hepatitis B virus (HBV) is a major cause of liver disease and cancer in humans. Mammalian HBV-like viruses are also found in nonhuman primates, rodents, and bats. As for most viruses, HBV requires a successful interaction with a host

关键词： Tropics   Ecology disease   Alphavirus   Public health  

摘要： Alphavirus infection associated encephalitis is an emerging infectious disease with a high impact on public health in Latin America. Objective: To study the eco-epidemiology of alphaviruses in bats of departments of Cordoba and Sucre, Colombia. Methodology: A prospective descriptive cross-sectional study with a non-probabilistic sampling, in 12 localities of Cordoba and Sucre was carried out. Using mist nets capture of the specimens was carried out. The size of the sample was 286 bats, each specimen captured was taxonomically classified. The bats were immobilized with anesthetic and analgesic treatment according to the ethics committee of the University of Cordoba, morphometric measurements and blood samples were taken, later they were necropsied in the field to obtain a collection of tissues which were preserved in liquid N-2 - 190 degrees C. The averages of the climatic conditions of the sampling sites were extracted from the WorldClim database (http://***/). The open source software QGIS (Quantum GIS Development Team.2015) was used to map and visualize bioclimatic regions of Cordoba. We used descriptive and retrospective information about the equine population and reports of foci of equine encephalitis. Results: In Cordoba and Sucre, 286 bats were captured and 23 species were classified, Artibeus and Phyllostomus discolor were the most frequent captured genus. The geographic ranges of the captured species were variable, some had a wide distribution and others were restricted to some areas. Venezuelan equine encephalitis virus RNA was detected in Artibeus planirostris and Sturnira lilium (2/286 = 0.70%) from Cordoba Colombia. The univariate descriptive analysis showed no significant association for any of the analyzed variables climatic. Conclusions: Frugivorous bats from the Caribbean area of Colombia may be involved in the Venezuelan equine encephalitis virus enzootic cycle.

关键词： 汉坦病毒   自然传播   肾综合征出血热   蝙蝠   啮齿动物   人兽共患   人类健康   自然宿主  

摘要： 汉坦病毒(HV)是严重威胁人类健康的重要人兽共患病原体。啮齿动物是该病原公认的自然宿主和传播动物,人感染后引起肾综合征出血热(Hemorrhagic fever with renal syndrome,HFRS)和汉坦病毒心肺综合征(Hantavirus cardiopulmonary syndrome,HCPS)二种疾病。前者主要在欧亚大陆流行,而后者主要在美洲流行。每年全球报告约10万例肾综合征出血热和近千例汉坦病毒心肺综合征。我国是肾综合征出血热流行比较严重的国家,仅2017年发病人数就高达11 262例,其中死亡病例64人。

关键词： 吸血蝙蝠   牛   狂犬病   基本再生数  

摘要： 根据吸血蝙蝠与牛之间狂犬病毒的传播机理建立数学模型,获得了吸血蝙蝠中狂犬病毒的传播阈值,分析了吸血蝙蝠系统中平衡点的稳定性,进一步讨论了牛群中狂犬病毒的传播,获得了正平衡点存在的条件。最后,对模型中的免疫率进行了敏感性分析。

摘要： In the last two decades, several high impact zoonotic disease outbreaks have been linked to bat-borne viruses. These include SARS coronavirus, Hendra virus and Nipah virus. In addition, it has been suspected that ebolaviruses and MERS coronavirus are also linked to bats. It is being increasingly accepted that bats are potential reservoirs of a large number of known and unknown viruses, many of which could spillover into animal and human populations. However, our knowledge into basic bat biology and immunology is very limited and we have little understanding of major factors contributing to the risk of bat virus spillover events. Here we provide a brief review of the latest findings in bat viruses and their potential risk of cross-species transmission.

关键词： Amniotes   Anatomy   Animal models of disease   Animal models of infection   Animal studies   Animals   Bats   Biology and life sciences   Body fluids   Digestive system   Eukaryota   Exocrine glands   Flaviviruses   Fruit bats   Genital anatomy   Histochemistry and cytochemistry techniques   Immunohistochemistry techniques   Immunologic techniques   Mammals   Medical microbiology   Medicine and health sciences   Microbial pathogens   Microbiology   Organisms   Pathogens   Pathology and laboratory medicine   Physiology   Reproductive system   Research and analysis methods   Research Article   RNA viruses   Salivary glands   Testes   Urine   Vertebrates   Viral pathogens   Viruses   Zika virus  

摘要： The emergence of Zika virus (ZIKV) in the New World has led to more than 200,000 human infections. Perinatal infection can cause severe neurological complications, including fetal and neonatal microcephaly, and in adults there is an association with Guillain-Barre syndrome (GBS). ZIKV is transmitted to humans by Aedes sp. mosquitoes, yet little is known about its enzootic cycle in which transmission is thought to occur between arboreal Aedes sp. mosquitos and non-human primates. In the 1950s and 60s, several bat species were shown to be naturally and experimentally susceptible to ZIKV with acute viremia and seroconversion, and some developed neurological disease with viral antigen detected in the brain. Because of ZIKV emergence in the Americas, we sought to determine susceptibility of Jamaican fruit bats (Artibeus jamaicensis), one of the most common bats in the New World. Bats were inoculated with ZIKV PRVABC59 but did not show signs of disease. Bats held to 28 days post-inoculation (PI) had detectable antibody by ELISA and viral RNA was detected by qRT-PCR in the brain, saliva and urine in some of the bats. Immunoreactivity using polyclonal anti-ZIKV antibody was detected in testes, brain, lung and salivary glands plus scrotal skin. Tropism for mononuclear cells, including macrophages/microglia and fibroblasts, was seen in the aforementioned organs in addition to testicular Leydig cells. The virus likely localized to the brain via infection of Iba1(+) macrophage/microglial cells. Jamaican fruit bats, therefore, may be a useful animal model for the study of ZIKV infection. This work also raises the possibility that bats may have a role in Zika virus ecology in endemic regions, and that ZIKV may pose a wildlife disease threat to bat populations. Author summary The rapid spread of Zika virus through a naive population in the Americas resulted in novel and severe disease manifestations, including fetal and neonatal microcephaly, and GBS. These disease complications m