关键词： Africa   Europe   Ghana   coronavirus   bats   human betacoronavirus   CoV-EMC   viruses  

摘要： We screened fecal specimens of 4,758 bats from Ghana and 272 bats from 4 European countries for betacoronaviruses. Viruses related to the novel human betacoronavirus EMC/2012 were detected in 46 (24.9%) of 185 Nycteris bats and 40 (14.7%) of 272 Pipistrellus bats. Their genetic relatedness indicated EMC/2012 originated from bats.

关键词： Rabies virus   European bat lyssavirus   Neuropathology   Pathogenicity   Murine  

摘要： A comparison of the clinicopathology of European bat lyssavirus (EBLV) types-1 and -2 and of rabies virus was undertaken. Following inoculation of mice at a peripheral site with these viruses, clinical signs of rabies and distribution of virus antigen in the mouse brain were examined. The appearance of clinical signs of disease varied both within and across the different virus species, with variation in incubation periods and weight loss throughout disease progression. The distribution of viral antigen throughout the regions of the brain examined was similar for each of the isolates during the different stages of disease progression, suggesting that antigen distribution was not associated with clinical presentation. However, specific regions of the brain including the cerebellum, caudal medulla, hypothalamus and thalamus, showed notable differences in the proportion of virus antigen positive cells present in comparison to other brain regions suggesting that these areas are important in disease development irrespective of virus species. Crown Copyright (c) 2013 Published by Elsevier B.V. All rights reserved.

关键词： Dengue virus   Experimental infection   Frugivorous bat   Chiroptera   Semi-nested RT-PCR  

摘要： Dengue fever is caused by a flavivirus that primarily infects humans and Aedes sp. mosquitoes. However, viral replication in wild animals other than non-human primates has been scarcely studied. In this report, the susceptibility of Artibeus intermedius frugivorous bat to serotype-2 dengue virus (DENV-2) infection was tested. Twenty-three bats were intraperitoneally inoculated with different viral loads of DENV-2 (New Guinea-C strain). Forty-three percent of the infected bats developed bruises on the chest or on the wings. Histological analyses showed structural alterations in the spleen and bleeding in liver and intestine, but the virus was not detected by RT-PCR in any of the analyzed tissues, and it was found in only one bat (kidney) by semi-nested RT-PCR. In sera, the viral RNA was detected by semi-nested RT-PCR in 39% of bats, but only 8% of bats seroconverted. Overall, these data indicate that DENV-2 replicates poorly in these bats, suggesting they are not suitable hosts to this virus. (c) 2012 Elsevier Ltd. All rights reserved.

关键词： BATS   RESEARCH   IMMUNOLOGY -- Research  

摘要： The article discusses research done by G. Zhang and colleagues on bat immunology, published in a 2013 issue of 'Science.'

关键词： Bats   experimental infection   rabies virus pathogenesis   thermography   surveillance  

摘要： Zoonotic disease surveillance is typically initiated after an animal pathogen has caused disease in humans. Early detection of potentially high-risk pathogens within animal hosts may facilitate medical interventions to cope with an emerging disease. To effectively spillover to a novel host, a pathogen may undergo genetic changes resulting in varying transmission potential in the new host and potentially to humans. Rabies virus (RABV) is one model pathogen to consider for studying the dynamics of emerging infectious diseases under both laboratory and field conditions. The evolutionary history of RABV is characterized by regularly documented spillover infections and a series of notable host shifts. Within this context, enhanced field surveillance to improve detection of spillover infections will require validated techniques to non-invasively differentiate infected from non-infected individuals. In this study, we evaluate the use of infrared thermography to detect thermal changes associated with experimental RABV infection in big brown bats (Eptesicus fuscus) in a captive colony. Our results indicated that 62% of rabid bats had detectable facial temperature decreases (-4.6 degrees C, SD +/- 2.5) compared with pre-inoculation baseline values. These data suggest potential utility for discriminating rabid bats in natural field settings. In addition, focusing upon RABV circulating in the United States between 2008 and 2011, we confirmed spillover events of bat RABV among carnivores and identified cross-species transmission events caused by four lineages of RABV associated with insectivorous bats. Additionally, our analysis of RABV glycoprotein sequences identified substitutions in antigenic sites that may affect neutralizing activity associated with monoclonal antibodies proposed for use in human post-exposure prophylaxis. This study provides a glimpse into RABV pathobiology and spillover dynamics among and between bats and a variety of mesocarnivores.

关键词： bats   fruit bats   Chiroptera   Ebola virus   filovirus   viruses   Rousettus leschenaultii   natural reservoir   serology   zoonoses   Bangladesh  

摘要： To determine geographic range for Ebola virus, we tested 276 bats in Bangladesh. Five (3.5%) bats were positive for antibodies against Ebola Zaire and Reston viruses;no virus was detected by PCR. These bats might be a reservoir for Ebola or Ebola-like viruses, and extend the range of filoviruses to mainland Asia.

关键词： Disease Outbreaks   Ebolavirus   RNA Viruses   Chiroptera   Epidemic   viruses  

摘要： Bats are being increasingly recognized as an important reservoir of zoonotic viruses of different families, including SARS coronavirus, Nipah virus, Hendra virus and Ebola virus. Several recent studies hypothesized that bats, an ancient group of flying mammals, are the major reservoir of several important RNA virus families from which other mammalian viruses of livestock and humans were derived. Although this hypothesis needs further investigation, the premise that bats carry a large number of viruses is commonly accepted. The question of whether bats have unique biological features making them ideal reservoir hosts has been the subject of several recent reviews. In this review, we will focus on the public health implications of bat derived zoonotic viral disease outbreaks, examine the drivers and risk factors of past disease outbreaks and outline research directions for better control of future disease events.

关键词： Bats   Chiroptera   viral infection   innate immunity   adaptive immunity  

摘要： Despite being the second most species-rich and abundant group of mammals, bats are also among the least studied, with a particular paucity of information in the area of bat immunology. Although bats have a long history of association with rabies, the emergence and re-emergence of a number of viruses from bats that impact human and animal health has resulted in a resurgence of interest in bat immunology. Understanding how bats coexist with viruses in the absence of disease is essential if we are to begin to develop therapeutics to target viruses in humans and susceptible livestock and companion animals. Here, we review the current status of knowledge in the field of bat antiviral immunology including both adaptive and innate mechanisms of immune defence and highlight the need for further investigations in this area. Because data in this field are so limited, our discussion is based on both scientific discoveries and theoretical predictions. It is hoped that by provoking original, speculative or even controversial ideas or theories, this review may stimulate further research in this important field. Efforts to understand the immune systems of bats have been greatly facilitated in recent years by the availability of partial genome sequences from two species of bats, a megabat, Pteropus vampyrus, and a microbat, Myotis lucifugus, allowing the rapid identification of immune genes. Although bats appear to share most features of the immune system with other mammals, several studies have reported qualitative and quantitative differences in the immune responses of bats. These observations warrant further investigation to determine whether such differences are associated with the asymptomatic nature of viral infections in bats.

关键词： Amino Acid Sequence   Animals   Biological Evolution   Chiroptera/genetics   Chiroptera/immunology   Chiroptera/physiology   DNA Damage/genetics   DNA Repair/genetics   Echolocation   Evolution, Molecular   Evolution, Molecular   Flight, Animal   Flight, Animal   Genetic Speciation   Genetic Speciation   Genome   Hibernation/genetics   Hibernation/genetics   High-Throughput Nucleotide Sequencing   Immunity, Innate/genetics   Immunity, Innate/genetics   Male   Molecular Sequence Data   Phylogeny   Phylogeny   Reactive Oxygen Species/metabolism   Selection, Genetic   Sequence Analysis, DNA   Species Specificity  

摘要： Bats are the only mammals capable of sustained flight and are notorious reservoir hosts for some of the world's most highly pathogenic viruses, including Nipah, Hendra, Ebola, and severe acute respiratory syndrome (SARS). To identify genetic changes associated with the development of bat-specific traits, we performed whole-genome sequencing and comparative analyses of two distantly related species, fruit bat Pteropus alecto and insectivorous bat Myotis davidii. We discovered an unexpected concentration of positively selected genes in the DNA damage checkpoint and nuclear factor kappa B pathways that may be related to the origin of flight, as well as expansion and contraction of important gene families. Comparison of bat genomes with other mammalian species has provided new insights into bat biology and evolution.

关键词： Bats   Immune system   Medical risk factors   Trophic interactions   Carnivora   Ecological risk   Parasitic diseases   White blood cells  

摘要： Ecological and social factors are central in the emergence and transmission of infectious diseases, thus bearing the potential for shaping a species' immune functions. Although previous studies demonstrated a link between social factors and the cellular immune system for captive mammals, it is yet poorly understood how ecological factors are connected with the different branches of the immune system in wild populations. Here, we tested how variation in aspects of the constitutive cellular and humoral immune system of free ranging bats is associated with two ecological factors that likely influence the putative risk of species to become infected by parasites and pathogens: diet and shelter. We found that white blood cell counts of 24 syntopic Neotropical bat species varied with the species' diet and body mass. Bats that included at least partially vertebrates in their diet exhibited the highest white blood cell counts, followed by phytophagous and insectivorous species, which is in agreement with the assumption that the immune system varies with the pathogen transmission risk of a trophic level. The soluble part of the constitutive immune response, assessed by an in vitro bacterial killing assay, decreased with increasing roost permanence. Our results suggest that the ecology is an important factor in the evolution of the immune system in bats and probably also other mammals.