Recent recognition of bats as reservoir hosts of emerging viruses

149 Bats (order Chiroptera, suborders Megachiroptera (»flying foxes«) and Microchiroptera) are abundant, diverse, and have been found on all continents except Antarctica. Although bats provide us with certain resources and many feed on insects, many populations of bats are at risk, threatened or endangered. The characteristics of these mammals include particular diets, colonial or solitary nature, ability to fly, cyclic migrations and daily movement patterns, the ability to enter torpor or to hibernate, long life span, roosting behaviors, a unique capacity to echolocate and, critically, their susceptibility to viruses make them suitable hosts of viruses, bacteria, parasites, fungi, and other disease agents. Although bats of certain species have long been known to transmit Rabies virus, they have been only rarely studied as hosts of viruses. Recent outbreaks and epidemics of newly recognized human and livestock diseases caused by bat-transmitted viruses have attracted the interest of scientific investigators to these mammals. This review summarizes germane facts regarding the characteristics of bats and provides information regarding 66 viruses that have been isolated from them. The literature on the biology of bats is abundant with respect to narrowly defined characters, including echolocation, diet, and distribution, but it is deficient with respect to bat biology in general. In addition, it is clear that bat conservation policies are inadequate and that we have merely begun to scratch the surface of a field of discovery regarding the roles of bats in disease emergence.