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Bats and Viruses: a Brief Review
Abstract
Abstract：Bats, probably the most abundant, diverse and geographically dispersed vertebrates on earth, have recently been shown to be the reservoir hosts of a number of emerging viruses responsible for severe human and livestock disease outbreaks. Flying foxes have been demonstrated to be the natural reservoir for Hendra and Nipah viruses. Evidence supporting the possibility of bats as potential reservoirs for SARS coronavirus (SARS-CoV) and Ebola virus has also been reported. The recent discovery of these viruses and other viruses occurring naturally in the bat population provides a unique insight into a diverse pool of potentially emergent and pathogenic viruses. The factors which influence the ability of zoonotic viruses to effectively cross the species barrier from bats to other animal populations are poorly understood. A brief review is provided here on the recently emerged bat viruses and on current and future strategies for research in this area.
Australia and several of them involved human infections. The latest outbreaks in 2008 resulted in the death of a veterinarian working with infected horses.
Approximately five years after the first Hendra virus outbreak, a very closely related virus, the Nipah virus, emerged in Malaysia, believed to be the result of a bat-to-pig spillover event(s). This was followed by massive pig-to-pig transmission and eventually led to pig-to-human transmission, and claimed more than 100 human lives in Malaysia and Singapore (4). A different strain of the Nipah virus has since emerged in India and Bangladesh, causing outbreaks almost on a yearly basis, with a mortality of up to 70 to 90%.
Epidemiological investigations suggest that this Nipah virus strain is capable of direct bat-to-human and human-to-human transmission, raising the possibility of a much larger outbreak in humans (13; 15) .
Hendra and Nipah viruses are now classified into a separate genus, Henipavirus, in the family Paramyxoviridae (8
The severe acute respiratory syndrome (SARS) virus was responsible for the first serious and widespread zoonotic disease outbreak of the 21 st century which exhibited efficient human-to-human transmission (23) . Although zoonotic SARS virus strains were isolated from civets and raccoon dogs (12) , and viral genomic materials were detected in cats,
As one of the most deadly viruses known to infect humans, the origin of Ebola virus remains a mystery.
However, a recent study has shown that bats of three Using the emergence of henipavirus as example, we can see these factors all play a role to some degree.
In Australia, it has been shown that the distribution of Is it unusual that so many emerging zoonotic viruses originated from bats? The answer to this question will be "yes" or "no" depending on how the question is
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