This could be the start of something big—20 years since the identification of bats as the natural host of Hendra virus

Black, Peter; Douglas, Ian; Field, Hume

Hendra virus was first described in 1994 in Australia, causally associated with a cluster of fatal equine and human cases at a thoroughbred racing stable in the Brisbane suburb of Hendra. This year marks the twentieth anniversary of the identification of pteropid bats (flying-foxes) as the natural host of the virus, and it is timely to reflect on a pivotal meeting of an eclectic group of scientists in that process. They included animal and public health experts, environmental scientists, veterinary and horse industry representatives, and wildlife experts. The task was to review and prioritise wildlife surveillance seeking the origin of the previously unknown virus. The group determined that the likely reservoir must occur in disparate locations, and be capable of moving between locations, or exist in continuous, overlapping populations spanning multiple locations. Flying-foxes were considered to be a more probable source of the novel virus than birds. Within weeks, antibodies were detected in several species of flying-fox, and the virus was subsequently isolated. While the identification of the natural host of Hendra virus within 18 months of its description was remarkable in itself, a broader legacy followed. In the subsequent years, a suite of zoonotic viruses including Australian bat lyssavirus, Nipah virus, SARS coronavirus, and Ebola and Marburg viruses have been detected in bats. Bats are now the "go to" taxa for novel viruses. History has repeatedly demonstrated that knowledge begets knowledge. This simple notion of bringing a diverse group of people together in an environment of mutual respect reinforced this principle and proves that the sum is often so much more powerful than the parts. Hendra virus, a novel zoonotic paramyxovirus, was first described in 1994 in Australia causally associated with a cluster of fatal equine and human cases at a thoroughbred racing stable in the Brisbane suburb of Hendra [1, 6, 9] . The subsequent identification of pteropid bats (Chiroptera: Pteropodidae) as the natural host of the virus precipitated a focus on bats as the source of emerging zoonoses that continues to this day. However, at that time, the identification of the reservoir of Hendra virus (initially known as equine morbillivirus) was urgent and confronting. This year marks the twentieth anniversary of the identification of the natural host for Hendra virus, and it is timely to reflect on a pivotal event in that process-the singular coming together of a group of scientists from diverse backgrounds at the Queensland Government Animal Research Institute in Brisbane in early 1996. The objective of the cross-disciplinary think tank was to review and revise research seeking the origins of Hendra virus, and its deliberations were key to the timely identification of the natural host.