关键词： MIDDLE East respiratory syndrome   CORONAVIRUS diseases   BATS   SERODIAGNOSIS   VIRAL genomes  

摘要： The emerging Middle East respiratory syndrome coronavirus (MERS-CoV) causes lethal respiratory infections mainly on the Arabian Peninsula. The evolutionary origins of MERS-CoV are unknown. We determined the full genome sequence of a CoV directly from fecal material obtained from a South African Neoromicia capensis bat (NeoCoV). NeoCoV shared essential details of genome architecture with MERS-CoV. Eighty-five percent of the NeoCoV genome was identical to MERS-CoV at the nucleotide level. Based on taxonomic criteria, NeoCoV and MERS-CoV belonged to one viral species. The presence of a genetically divergent S1 subunit within the NeoCoV spike gene indicated that intraspike recombination events may have been involved in the emergence of MERS-CoV. NeoCoV constitutes a sister taxon of MERS-CoV, placing the MERS-CoV root between a recently described virus from African camels and all other viruses. This suggests a higher level of viral diversity in camels than in humans. Together with serologic evidence for widespread MERS-CoV infection in camelids sampled up to 20 years ago in Africa and the Arabian Peninsula, the genetic data indicate that camels act as sources of virus for humans rather than vice versa. The majority of camels on the Arabian Peninsula is imported from the Greater Horn of Africa, where several Neoromicia species occur. The acquisition of MERS-CoV by camels from bats might have taken place in sub-Saharan Africa. Camelids may represent mixing vessels for MERS-CoV and other mammalian CoVs. IMPORTANCE It is unclear how, when, and where the highly pathogenic MERS-CoV emerged. We characterized the full genome of an African bat virus closely related to MERS-CoV and show that human, camel, and bat viruses belong to the same viral species. The bat virus roots the phylogenetic tree of MERS-CoV, providing evidence for an evolution of MERS-CoV in camels that preceded that in humans. The revised tree suggests that humans are infected by camels rather than vice versa. Al

关键词： Biology and life sciencesEvolutionary biologyGeneticsInfectious diseasesMedicine and health sciencesMicrobiologyMolecular biologyPathology and laboratory medicineResearch ArticleSynthetic biology  

摘要： Bats harbor many viruses, which are periodically transmitted to humans resulting in outbreaks of disease (e. g., Ebola, SARS-CoV). Recently, influenza virus-like sequences were identified in bats;however, the viruses could not be cultured. This discovery aroused great interest in understanding the evolutionary history and pandemic potential of bat-influenza. Using synthetic genomics, we were unable to rescue the wild type bat virus, but could rescue a modified bat-influenza virus that had the HA and NA coding regions replaced with those of A/PR/8/1934 (H1N1). This modified bat-influenza virus replicated efficiently in vitro and in mice, resulting in severe disease. Additional studies using a bat-influenza virus that had the HA and NA of A/swine/Texas/4199-2/1998 (H3N2) showed that the PR8 HA and NA contributed to the pathogenicity in mice. Unlike other influenza viruses, engineering truncations hypothesized to reduce interferon antagonism into the NS1 protein didn't attenuate bat-influenza. In contrast, substitution of a putative virulence mutation from the bat-influenza PB2 significantly attenuated the virus in mice and introduction of a putative virulence mutation increased its pathogenicity. Mini-genome replication studies and virus reassortment experiments demonstrated that bat-influenza has very limited genetic and protein compatibility with Type A or Type B influenza viruses, yet it readily reassorts with another divergent bat-influenza virus, suggesting that the bat-influenza lineage may represent a new Genus/Species within the Orthomyxoviridae family. Collectively, our data indicate that the bat-influenza viruses recently identified are authentic viruses that pose little, if any, pandemic threat to humans;however, they provide new insights into the evolution and basic biology of influenza viruses.

关键词： Usutu virus   viruses   full-length genome   Pipistrellus bat   phylogeny   Germany  

摘要： The article discusses a study which examined the presence of the flavivirus Usutu virus (USUV) in dead bats in southwest Germany. Topics discussed include extraction and analysis of DNA and RNA from the bats, reverse transcriptase polymerase chain reaction (PCR) analysis to determine the presence of flavivirus and rhabdovirus, and genome sequencing of USUV strains.

关键词： Age Factors   Animals   Chiroptera/blood   Chiroptera/immunology   Chiroptera/parasitology   Costa Rica   Immunosenescence   Longevity  

摘要： The immune system imposes costs that may have to be traded against investment of resources in other costly life-history traits. Yet, it is unknown if a trade-off between immunity and longevity occurs in free-ranging mammals. Here, we tested if age and survival, two aspects associated with longevity, are linked to immune parameters in an 8 g bat species. Using a combination of cross-sectional and longitudinal data, we assessed whether total white blood cell (WBC) counts, bacterial killing ability of the plasma (BKA) and immunoglobulin G (IgG) concentration change with age. Furthermore, we asked if these immune parameters impose costs resulting in decreased survival probabilities. We found that WBC counts decreased with age both within and among individuals. IgG concentrations were higher in older individuals, but did not change with age within individuals. Furthermore, individuals with above average WBC counts or IgG concentration had lower probabilities to survive the next six months. High WBC counts and IgG concentrations may reflect infections with parasites and pathogens, however, individuals that were infected with trypanosomes or nematodes showed neither higher WBC counts or IgG concentrations, nor was infection connected with survival rates. BKA was higher in infected compared with uninfected bats, but not related to age or survival. In conclusion, cellular (WBC) and humoral (IgG) parts of the immune system were both connected to age and survival, but not to parasite infections, which supports the hypothesis that energetically costly immunological defences are traded against other costly life-history traits, leading to a reduced lifespan in this free-ranging mammal.

关键词： 甲型流感病毒   甲型流感病毒聚合酶   蝙蝠   适应突变  

摘要： 本研究通过对蝙蝠中高度不同的甲型流感病毒的研究发现了新的、地理位置分散的病毒库。为调查宿主限制性病毒嗜性的分子机制及病毒在人类和蝙蝠之间传播的潜力,本研究将来自不同品种的蝙蝠细胞系与人源甲型流感病毒原型株一起进行试验。结果显示试验用的所有蝙蝠细胞株均对甲型流感病毒易感,蝙蝠细胞中人类和禽类流感病毒的进化导致了病毒的有效复制并产生了高度细胞病变的变种。对适应人类的甲型流感病毒的深度测序揭示了以前未报道过的PA聚合酶亚基M285K的突变。编码PA M285K的重组病毒完全改变适应病毒的表型。禽类病毒的适应导致其他哺乳动物有效复制所需的PB2E627K发生突变。没有一个适应突变发生在为识别唾液酸受体宿主特异性变化而经常发生基因改变的病毒血细胞凝集素上。研究结果发现,人源流感病毒利用典型的唾液酸受体感染蝙蝠细胞,即使蝙蝠流感病毒似乎并没有使用这些受体的病毒入口。结果表明,蝙蝠是支持病毒聚合酶新的或众所周知的适应突变独一无二的宿主。

关键词： 蝙蝠   汉坦病毒   自然宿主  

摘要： 汉坦病毒是一种人兽共患病病原,通过RT-PCR扩增汉坦病毒M片段基因序列检测我国广东蝙蝠,首次在广东地区健康蝙蝠样品中扩增出长度约170 bp的汉坦病毒cDNA片段,测序证实为汉坦病毒的M片段序列,同源性达到99%以上。共检测了5个蝙蝠种类的74只蝙蝠的咽、肛拭子样品,阳性率为12.16%。说明蝙蝠也携带和传播汉坦病毒,是汉坦病毒的宿主动物。鉴于蝙蝠与人类关系越来越密切,提醒我们在畜牧业和种植业工作中要加强防范蝙蝠传播病毒给家养动物和人类。

关键词： 蝙蝠   细小病毒   分离   鉴定   基因型  

摘要： 目的对1株蝙蝠来源病毒进行分离鉴定,进行简单的基因分析。方法从云南沧源县8个居民地附近捕获50只棕果蝠并制作组织标本,采用细胞培养分离病毒,采用cDNA-RAPD方法扩增序列,采用分子克隆进一步扩增序列,将序列在NCBI上进行BLAST比对,采用DNAMAN5.0进行同源性分析,采用MEGA 5建序列进化树。结果 50份接毒细胞中,6份细胞出现细胞病变,cDNA-RAPD扩增得到1份阳性片段,测序大小为614 bp,经比对该病毒株是细小病毒科细小病毒亚科博卡病毒属牛细小病毒种的一个毒株。结论成功分离并鉴定该毒株,确定该病毒是牛细小病毒的一个新的基因型。

关键词： Chiroptera   Redox status   Oxidative damage   Immune defence   Ectoparasites  

摘要： Harmful reactive oxygen species (ROS) produced during metabolism and immune responses are neutralized in part by a powerful enzymatic antioxidant system. Inter-species variability in the baseline activity of antioxidant enzymes may be explained by a variety of life history traits. For instance, ectoparasites can elicit repeated immune responses, thus increasing the production of reactive oxygen species. The bat species studied so far have been acknowledged to have effective antioxidant defences. However, interspecific comparisons within the clade do not exist. The present study compares the antioxidant defence and immune function activities in five northern boreal bat species relative to their ectoparasite prevalence and intensity (wing mites and louse flies) to reveal inter-species differences. Antioxidant enzyme and immune defense activities, which differ between species, are positively associated, with total ectoparasite (mites and bat flies) frequencies, total ROS, and protein carbonylation in Daubenton's bats, but enzyme activities are also independently influenced by sampling date with activities increasing towards the autumn. Antioxidant activities are also positively associated with total reactive oxygen species and oxidative damage (protein carbonylation) in the Daubenton's bat. Our results suggest that antioxidant activities are associated with ecological factors such as parasite load and season, and we consider it likely that these may partly explain the observed interspecific variation.

关键词： Africa   Animals   Biodiversity   Biodiversity   Chiroptera/classification   Chiroptera/virology   Communicable Diseases, Emerging/transmission   Cytochromes b/genetics   Disease Reservoirs/veterinary   Geography   Phylogeny   Phylogeny   Population Density   Population Dynamics   Viruses/isolation & purification  

摘要： The rising incidence of emerging infectious diseases (EID) is mostly linked to biodiversity loss, changes in habitat use and increasing habitat fragmentation. Bats are linked to a growing number of EID but few studies have explored the factors of viral richness in bats. These may have implications for role of bats as potential reservoirs. We investigated the determinants of viral richness in 15 species of African bats (8 Pteropodidae and 7 microchiroptera) in Central and West Africa for which we provide new information on virus infection and bat phylogeny. We performed the first comparative analysis testing the correlation of the fragmented geographical distribution (defined as the perimeter to area ratio) with viral richness in bats. Because of their potential effect, sampling effort, host body weight, ecological and behavioural traits such as roosting behaviour, migration and geographical range, were included into the analysis as variables. The results showed that the geographical distribution size, shape and host body weight have significant effects on viral richness in bats. Viral richness was higher in large-bodied bats which had larger and more fragmented distribution areas. Accumulation of viruses may be related to the historical expansion and contraction of bat species distribution range, with potentially strong effects of distribution edges on virus transmission. Two potential explanations may explain these results. A positive distribution edge effect on the abundance or distribution of some bat species could have facilitated host switches. Alternatively, parasitism could play a direct role in shaping the distribution range of hosts through host local extinction by virulent parasites. This study highlights the importance of considering the fragmentation of bat species geographical distribution in order to understand their role in the circulation of viruses in Africa.

关键词： Algorithms   Animals   Chiroptera/virology   Epidemiologic Factors   Female   Lyssavirus/classification   Lyssavirus/genetics   Male   Models, Theoretical   Rabies/epidemiology   Rabies/transmission   Rabies/virology   Rhabdoviridae Infections/epidemiology   Rhabdoviridae Infections/transmission   Rhabdoviridae Infections/virology   Seroepidemiologic Studies   Spain   Zoonoses/epidemiology   Zoonoses/transmission   Zoonoses/virology  

摘要： Rabies is a worldwide zoonosis resulting from Lyssavirus infection. In Europe, Eptesicus serotinus is the most frequently reported bat species infected with Lyssavirus, and thus considered to be the reservoir of European bat Lyssavirus type 1 (EBLV-1). To date, the role of other bat species in EBLV-1 epidemiology and persistence remains unknown. Here, we built an EBLV-12transmission model based on local observations of a three-cave and four-bat species (Myotis capaccinii, Myotis myotis, Miniopterus schreibersii, Rhinolophus ferrumequinum) system in the Balearic Islands, for which a 1995-2011 serological dataset indicated the continuous presence of EBLV-1. Eptesicus serotinus was never observed in the system during the 16-year follow-up and therefore was not included in the model. We used the model to explore virus persistence mechanisms and to assess the importance of each bat species in the transmission dynamics. We found that EBLV-1 could not be sustained if transmission between M. schreibersii and other bat species was eliminated, suggesting that this species serves as a regional reservoir. Global sensitivity analysis using Sobol's method revealed that following the rate of autumn-winter infectious contacts, M. schreibersii's incubation-and immune-period durations, but not the infectious period length, were the most relevant factors driving virus persistence.