Prior to the discovery of the Reston ebolavirus (RESTV) in 1989, filoviruses were thought to be present only in Africa. The virus was discovered in a quarantine facility in Reston, Virginia, USA, following the deaths of imported cynomolgus macaques (Macaca fascicularis) from the Philippines displaying severe haemorrhagic disease. It was thought that aerosol and fomite transmission of RESTV occurred between the macaques and humans during this outbreak. In addition to RESTV, the macaques were found to be infected with the Arterivirus, Simian haemorrhagic fever virus, which naturally occurs in African monkeys. An epizootic event involving the cynomolgus macaques occurred again in 1992 in Siena, Italy and in 1996 in Alice, Texas, USA. All of these infections were traced to monkeys exported from a single primate facility located south of metropolitan Manila, on the island of Luzon in the Philippines. This facility was subsequently closed down by the government in 1997 due to non-compliance issues relating to environmental regulations. RESTV has also emerged in pigs in the Philippines in 2008 and China in 2011 where in both cases coinfection with porcine reproductive and respiratory syndrome virus (PRRSV) occurred. It was hypothesized that the source of these outbreaks were from exposure to bats.