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Bats carry a great diversity of zoonotic viruses with a high-impact on human health and livestock. Since the emergence of new coronaviruses and paramyxoviruses in humans (e.g. Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Nipah virus), numerous studies clearly established that bats can maintain some of these viruses. Improving our understanding on the role of bats in the epidemiology of the pathogens they harbour is necessary to prevent cross-species spill over along the wild/domestic/human gradient. In this study, we screened bat faecal samples for the presence of Coronavirus and Paramyxovirus in two caves frequently visited by local people to collect manure and/or to hunt bats in Zimbabwe. We amplified partial RNA-dependent RNA polymerase genes of Alpha and Betacoronavirus together with the partial polymerase gene of Paramyxovirus . Identified coronaviruses were related to pathogenic human strains and the paramyxovirus belonged to the recently described Jeilongvirus genus. Our results highlighted the importance of monitoring virus circulation in wildlife, especially bats, in the context of intense human-wildlife interfaces in order to strengthen prevention measures among local populations and to implement sentinel surveillance in sites with high zoonotic diseases transmission potential. [ABSTRACT FROM AUTHOR]

Preventing emergence of new zoonotic viruses depends on understanding determinants for human risk. Nipah virus (NiV) is a lethal zoonotic pathogen that has spilled over from bats into human populations, with limited person-to-person transmission. We examined ecologic and human behavioral drivers of geographic variation for risk of NiV infection in Bangladesh. We visited 60 villages during 2011-2013 where cases of infection with NiV were identified and 147 control villages. We compared case villages with control villages for most likely drivers for risk of infection, including number of bats, persons, and date palm sap trees, and human date palm sap consumption behavior. Case villages were similar to control villages in many ways, including number of bats, persons, and date palm sap trees, but had a higher proportion of households in which someone drank sap. Reducing human consumption of sap could reduce virus transmission and risk for emergence of a more highly transmissible NiV strain. [ABSTRACT FROM AUTHOR]

Bat-borne viruses have been linked to a number of zoonotic diseases; in 2014 there have been human cases of Nipah virus (NiV) in Bangladesh and Ebola virus in West and Central Africa. Here we describe a model designed to provide initial quantitative predictions of the risk of entry of such viruses to European Union (EU) Member States (MSs) through four routes: human travel, legal trade (e.g. fruit and animal products), live animal movements and illegal importation of bushmeat. The model utilises available datasets to assess the movement via these routes between individual countries of the world and EU MSs. These data are combined with virus specific data to assess the relative risk of entry between EU MSs. As a case study, the model was parameterised for NiV. Scenario analyses showed that the selection of exporting countries with NiV and potentially contaminated trade products were essential to the accuracy of all model outputs. Uncertainty analyses of other model parameters identified that the model expected number of years to an introduction event within the EU was highly susceptible to the prevalence of NiV in bats. The relative rankings of the MSs and routes, however, were more robust. The UK, the Netherlands and Germany were consistently the most likely points of entry and the ranking of most MSs varied by no more than three places (maximum variation five places). Legal trade was consistently the most likely route of entry, only falling below human travel when the estimate of the prevalence of NiV in bats was particularly low. Any model-based calculation is dependent on the data available to feed into the model and there are distinct gaps in our knowledge, particularly in regard to various pathogen/virus as well as host/bat characteristics. However, the strengths of this model lie in the provision of relative comparisons of risk among routes and MSs. The potential for expansion of the model to include other routes and viruses and the possibility of rapid parameterisation demonstrates its potential for use in an outbreak situation. [ABSTRACT FROM AUTHOR]

Nipah virus (NiV) is a paramyxovirus, and Pteropus spp. bats are the natural reservoir. From December 2010 through March 2014, hospital-based encephalitis surveillance in Bangladesh identified 18 clusters of NiV infection. The source of infection for case-patients in 3 clusters in 2 districts was unknown. A team of epidemiologists and anthropologists investigated these 3 clusters comprising 14 case-patients, 8 of whom died. Among the 14 case-patients, 8 drank fermented date palm sap (tari) regularly before their illness, and 6 provided care to a person infected with NiV. The process of preparing date palm trees for tari production was similar to the process of collecting date palm sap for fresh consumption. Bat excreta was reportedly found inside pots used to make tari. These findings suggest that drinking tari is a potential pathway of NiV transmission. Interventions that prevent bat access to date palm sap might prevent tari-associated NiV infection. [ABSTRACT FROM AUTHOR]

In recent years severe infectious diseases have been constantly emerging, causing panic in the world. Now we know that many of these terrible diseases are caused by viruses originated from bats (Table 1), such as Ebola virus, Marburg, SARS coronavirus (SARS-CoV), MERS coronavirus (MERS-CoV), Nipah virus (NiV) and Hendra virus (HeV). These viruses have co-evolved with bats due to bats’ special social, biological and immunological features. Although bats are not in close contact with humans, spillover of viruses from bats to intermediate animal hosts, such as horses, pigs, civets, or non-human primates, is thought to be the most likely mode to cause human infection. Humans may also become infected with viruses through aerosol by intruding into bat roosting caves or via direct contact with bats, such as catching bats or been bitten by bats. [ABSTRACT FROM AUTHOR]

Bats are reservoir hosts of several high-impact viruses that cause significant human diseases, including Nipah virus, Marburg virus and rabies virus. They also harbor many other viruses that are thought to have caused disease in humans after spillover into intermediate hosts, including SARS and MERS coronaviruses. As is usual with reservoir hosts, these viruses apparently cause little or no pathology in bats. Despite the importance of bats as reservoir hosts of zoonotic and potentially zoonotic agents, virtually nothing is known about the host/virus relationships; principally because few colonies of bats are available for experimental infections, a lack of reagents, methods and expertise for studying bat antiviral responses and immunology, and the difficulty of conducting meaningful field work. These challenges can be addressed, in part, with new technologies that are species-independent that can provide insight into the interactions of bats and viruses, which should clarify how the viruses persist in nature, and what risk factors might facilitate transmission to humans and livestock. [ABSTRACT FROM AUTHOR]

Background: Population-level studies of parasites have the potential to elucidate patterns of host movement and cross-species interactions that are not evident from host genealogy alone. Bat flies are obligate and generally hostspecific blood-feeding parasites of bats. Old-World flies in the family Nycteribiidae are entirely wingless and depend on their hosts for long-distance dispersal; their population genetics has been unstudied to date. Methods: We collected a total of 125 bat flies from three Pteropus species (Pteropus vampyrus, P. hypomelanus, and P. lylei) from eight localities in Malaysia, Cambodia, and Vietnam. We identified specimens morphologically and then sequenced three mitochondrial DNA gene fragments (CoI, CoII, cytB; 1744 basepairs total) from a subset of 45 bat flies. We measured genetic diversity, molecular variance, and population genetic subdivision (FST), and used phylogenetic and haplotype network analyses to quantify parasite genetic structure across host species and localities. Results: All flies were identified as Cyclopodia horsfieldi with the exception of two individuals of Eucampsipoda sundaica. Low levels of population genetic structure were detected between populations of Cyclopodia horsfieldi from across a wide geographic range (∼1000 km), and tests for isolation by distance were rejected. AMOVA results support a lack of geographic and host-specific population structure, with molecular variance primarily partitioned within populations. Pairwise FST values from flies collected from island populations of Pteropus hypomelanus in East and West Peninsular Malaysia supported predictions based on previous studies of host genetic structure. Conclusions: The lack of population genetic structure and morphological variation observed in Cyclopodia horsfieldi is most likely due to frequent contact between flying fox species and subsequent high levels of parasite gene flow. Specifically, we suggest that Pteropus vampyrus may facilitate movement of bat flies between the three Pteropus species in the region. We demonstrate the utility of parasite genetics as an additional layer of information to measure host movement and interspecific host contact. These approaches may have wide implications for understanding zoonotic, epizootic, and enzootic disease dynamics. Bat flies may play a role as vectors of disease in bats, and their competence as vectors of bacterial and/or viral pathogens is in need of further investigation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Fruit bats of the genus Pteropus (commonly known as flying-foxes) are the natural hosts of several recently emerged zoonotic viruses of animal and human health significance in Australia and Asia, including Hendra and Nipah viruses. Satellite telemetry was used on nine flying-foxes of three species ( Pteropus alecto n = 5, P. vampyrus n = 2, and P. neohibernicus n = 2) to determine the scale and pattern of their long-distance movements and their potential to transfer these viruses between countries in the region. The animals were captured and released from six different locations in Australia, Papua New Guinea, Indonesia, and Timor-Leste. Their movements were recorded for a median of 120 (range, 47-342) days with a median total distance travelled of 393 (range, 76-3011) km per individual. Pteropus alecto individuals were observed to move between Australia and Papua New Guinea (Western Province) on four occasions, between Papua New Guinea (Western Province) and Indonesia (Papua) on ten occasions, and to traverse Torres Strait on two occasions. Pteropus vampyrus was observed to move between Timor-Leste and Indonesia (West Timor) on one occasion. These findings expand upon the current literature on the potential for transfer of zoonotic viruses by flying-foxes between countries and have implications for disease risk management and for the conservation management of flying-fox populations in Australia, New Guinea, and the Lesser Sunda Islands. [ABSTRACT FROM AUTHOR]

Nipah virus (NiV) is a paramyxovirus whose reservoir host is fruit bats of the genus Pteropus. Occasionally the virus is introduced into human populations and causes severe illness characterized by encephalitis or respiratory disease. The first outbreak of NiV was recognized in Malaysia, but 8 outbreaks have been reported from Bangladesh since 2001. The primary pathways of transmission from bats to people in Bangladesh are through contamination of raw date palm sap by bats with subsequent consumption by humans and through infection of domestic animals (cattle, pigs, and goats), presumably from consumption of food contaminated with bat saliva or urine with subsequent transmission to people. Approximately onehalf of recognized Nipah case patients in Bangladesh developed their disease following person-to-person transmission of the virus. Efforts to prevent transmission should focus on decreasing bat access to date palm sap and reducing family members' and friends' exposure to infected patients' saliva. [ABSTRACT FROM AUTHOR]

Human Nipah outbreaks recur in a specific region and time of year in Bangladesh. Fruit bats are the reservoir host for Nipah virus. We identified 23 introductions of Nipah virus into human populations in central and northwestern Bangladesh from 2001 through 2007. Ten introductions affected multiple persons (median 10). Illness onset occurred from December through May but not every year. We identified122 cases of human Nipah infection. The mean age of case-patients was 27 years; 87 (71%) died. In 62 (51%) Nipah virus--infected patients, illness developed 5-15 days after close contact with another Nipah case-patient. Nine (7%) Nipah case-patients transmitted virus to others. Nipah case-patients who had difficulty breathing were more likely than those without respiratory difficulty to transmit Nipah (12% vs. 0%, p = 0.03). Although a small minority of infected patients transmit Nipah virus, more than half of identified cases result from person-to-person transmission. Interventions to prevent virus transmission from bats to humans and from person to person are needed. [ABSTRACT FROM AUTHOR]

Abstract: Following the discovery of two new paramyxoviruses in the 1990s, much effort has been placed on rapidly finding the reservoir hosts, characterising the genomes, identifying the viral receptors and formulating potential vaccines and therapeutic options for these viruses, Hendra and Nipah viruses caused zoonotic disease on a scale not seen before with other paramyxoviruses. Nipah virus particularly caused high morbidity and mortality in humans and high morbidity in pig populations in the first outbreak in Malaysia. Both viruses continue to pose a threat with sporadic outbreaks continuing into the 21st century. Experimental and surveillance studies identified that pteropus bats are the reservoir hosts. Research continues in an attempt to understand events that precipitated spillover of these viruses. Discovered on the cusp of the molecular technology revolution, much progress has been made in understanding these new viruses. This review endeavours to capture the depth and breadth of these recent advances. [Copyright &y& Elsevier]

The article discusses a study which investigated group C betacoronavirus in bat guano fertilizer in Thailand. Bat guano from a cave in Ratchaburi Province were examined to asses pathogens. It was found that all bat guano samples screened by polymerase chain reaction (PCR) were negative for Nipah virus (NiV) and Histoplasma capsulatum but were positive for group C betacoronavirus.