关键词： bats   rabies   Brazil   Para  

摘要： Rabies is an acute, progressive zoonotic viral infection that in general produces a fatal outcome. This disease is responsible for deaths in humans and animals worldwide and, because it can affect all mammals, is considered one of the most important viral infections for public health. This study aimed to determine the prevalence of rabies in bats of different species found in municipalities of the state of Para from 2005 to 2011. The rabies virus was detected in 12 (0.39%) bats in a total of 3100 analyzed, including hematophagous, frugivorous, and insectivorous bats. Of these, eleven were characterized as AgV3, which is characteristic of the hematophagous bat Desmodus rotundus (E. Geoffroy 1810);one insectivorous animal showed a different profile compatible with the Eptesicus pattern and may therefore be a new antigenic variant. This study identified the need for greater intensification of epidemiological surveillance in municipalities lacking rabies surveillance (silent areas);studies of rabies virus in bats with different alimentary habits, studies investigating the prevalence of AgV3, and prophylactic measures in areas where humans may be infected are also needed.

摘要： Bats are natural reservoir hosts of highly virulent pathogens such as Marburg virus, Nipah virus, and SARS coronavirus. However, little is known about the role of bat ectoparasites in transmitting and maintaining such viruses. The intricate relationship between bats and their ectoparasites suggests that ectoparasites might serve as viral vectors, but evidence to date is scant. Bat flies, in particular, are highly specialized obligate hematophagous ectoparasites that incidentally bite humans. Using next-generation sequencing, we discovered a novel ledantevirus (mononegaviral family Rhabdoviridae, genus Ledantevirus) in nycteribiid bat flies infesting pteropodid bats in western Uganda. Mitochondrial DNA analyses revealed that both the bat flies and their bat hosts belong to putative new species. The coding-complete genome of the new virus, named Kanyawara virus (KYAV), is only distantly related to that of its closest known relative, Mount Elgon bat virus, and was found at high titers in bat flies but not in blood or on mucosal surfaces of host bats. Viral genome analysis indicates unusually low CpG dinucleotide depletion in KYAV compared to other ledanteviruses and rhabdovirus groups, with KYAV displaying values similar to rhabdoviruses of arthropods. Our findings highlight the possibility of a yet-to-be-discovered diversity of potentially pathogenic viruses in bat ectoparasites.

关键词： 白血病病毒   蝙蝠   科学家   祖先   机体   逆转录病毒   研究人员   化石记录  

摘要： 近日，一项刊登在国际杂志PNAS上的研究报告中，来自格拉斯哥大学和捷克科学院的研究人员通过研究在蝙蝠的基因组中发现了引发罕见类型白血病的病毒家族的古老DNA痕迹。这或许就填补了研究者关于逆转录病毒化石记录研究的关键缺口，研究者表示。这些病毒生活在距今2000万至4500万年前。

关键词： 人畜共患病   关系数据库   埃博拉病毒   重要研究成果   人类病毒   Nature   影响因素   项目监控   自啮   亲缘关系  

摘要： 英国《Nature》杂志6月20日发表了一项病毒学重要研究成果:美国科学家利用创建的庞大数据库,分析了动物携带多种病毒传人的可能性。该研究识别了影响病毒能否由动物传播给人类的重要因素,并给出最有可能对人类健康构成新威胁的地理位置,以及哺乳动物物种的图谱。人类免疫缺陷病毒(HIV)、埃博拉病毒和严重急性呼吸综合征(SARS)等大多数新发人类传染病,

关键词： Flying foxes   Spillover   Survival   Environmental transmission   Horses   Microclimates  

摘要： Infectious diseases are transmitted when susceptible hosts are exposed to pathogen particles that can replicate within them. Among factors that limit transmission, the environment is particularly important for indirectly transmitted parasites. To try and assess a pathogens' ability to be transmitted through the environment and mitigate risk, we need to quantify its decay where transmission occurs in space such as the microclimate harbouring the pathogen. Hendra virus, a Henipavirus from Australian Pteropid bats, spills-over to horses and humans, causing high mortality. While a vaccine is available, its limited uptake has reduced opportunities for adequate risk management to humans, hence the need to develop synergistic preventive measures, like disrupting its transmission pathways. Transmission likely occurs shortly after virus excretion in paddocks;however, no survival estimates to date have used real environmental conditions. Here, we recorded microclimate conditions and fitted models that predict temperatures and potential evaporation, which we used to simulate virus survival with a temperature-survival model and modification based on evaporation. Predicted survival was lower than previously estimated and likely to be even lower according to potential evaporation. Our results indicate that transmission should occur shortly after the virus is excreted, in a relatively direct way. When potential evaporation is low, and survival is more similar to temperature dependent estimates, transmission might be indirect because the virus can wait several hours until contact is made. We recommend restricting horses' access to trees during night time and reducing grass under trees to reduce virus survival.

关键词： Kaeng Khoi virus   Bat fly   China-Myanmar border  

摘要： A virus strain (WDBC1210) was isolated from specimens of bat flies (Eucampsipoda sundaica) associated with Leschenault's Rousette (Rousettus leschenaultii) in the China-Myanmar border area of Yunnan Province, China. Both BHK-21 and VeroE6 cells infected with WDBC1210 showed evident cytopathic effects (CPE), and the highest propagation titer was 1 x 10(5.6). The virus particles were spherical, 70 nm in diameter. Virus plaques could be observed in BHK-21 cells. The whole genome of WDBC1210 contained three RNA segments: the small gene (S), 975 nucleotides long;the medium gene (M), 4568 nucleotides long;and the large gene (L), 6866 nucleotides long. The nucleotide homologies of the S, M, and L genes between WDBC1210 and the original isolate of Kaeng Khoi virus (KKV;PSC-19 strain) were 96.9%, 94.1%, and 95.2%, respectively. Phylogenetic analyses based on the S, M, and L segments indicated that WDBC1210 belongs within the same Glade as the KKV strain PSC-19, a member of the Bunyaviridae family. This is the first report on the isolation of KKV from bat flies (Eucampsipoda sundaica) and from an inland area, nearly 2000 km north from the original isolation site of KKV in Thailand, suggesting that KKV virus not only has a diverse set of vectors, but also a wide geographic distribution.

关键词： 白血病病毒   科学院   蝙蝠   祖先   机体   研究人员   DNA   基因组  

摘要： 近日,一项刊登在国际杂志PNAS上的研究报告中,来自格拉斯哥大学和捷克科学院的研究人员通过研究在蝙蝠的基因组中发现了引发罕见类型白血病的病毒家族的古老DNA痕迹。

关键词： Rabies virus   Bats   Infection   Antibodies   RFFIT   hnRT   CR  

摘要： Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n = 35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n= 3), stomach (n= 1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRTPCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild.

关键词： 冠状病毒   科学家   蝙蝠   呼吸综合征病毒   基因组测序   乌干达   研究人员   人类健康  

摘要： 2017年4月4日,美国和乌干达研究人员在乌干达蝙蝠身上找到了与中东呼吸综合征病毒类似的一种新型冠状病毒,这种新型冠状病毒被命名为“PDF-2180”,是科学家从乌干达南部捕获的一只蝙蝠身上发现的.基因组测序结果显示,这种病毒与引发中东呼吸综合征的冠状病毒一致度达87%,但它用于入侵细胞的刺突基因与中东呼吸综合征病毒的刺突基因一致度只有46%.以目前的形态,这种病毒可能不会对人类健康构成威胁.

关键词： Bats   Rabies virus   Phylogenetic analysis   British Columbia   Canada   Sequence analysis   Geographic distribution   Sequence databases  

摘要： As rabies in carnivores is increasingly controlled throughout much of the Americas, bats are emerging as a significant source of rabies virus infection of humans and domestic animals. Knowledge of the bat species that maintain rabies is a crucial first step in reducing this public health problem. In North America, several bat species are known to be rabies virus reservoirs but the role of bats of the Myotis genus has been unclear due to the scarcity of laboratory confirmed cases and the challenges encountered in species identification of poorly preserved diagnostic submissions by morphological traits alone. This study has employed a collection of rabid bat specimens collected across Canada over a 25 year period to clearly define the role of particular Myotis species as rabies virus reservoirs. The virus was characterised by partial genome sequencing and host genetic barcoding, used to confirm species assignment of specimens, proved crucial to the identification of certain bat species as disease reservoirs. Several variants were associated with Myotis species limited in their Canadian range to the westernmost province of British Columbia while others were harboured by Myotis species that circulate across much of eastern and central Canada. All of these Myotis-associated viral variants, except for one, clustered as a monophyletic MYCAN clade, which has emerged from a lineage more broadly distributed across North America;in contrast one distinct variant, associated with the long-legged bat in Canada, represents a relatively recent host jump from a big brown bat reservoir. Together with evidence from South America, these findings demonstrate that rabies virus has emerged in the Myotis genus independently on multiple occasions and highlights the potential for emergence of new viral-host associations within this genus.