Figure

Figure. Spectacled flying fox (Pteropus conspicullatus) feeding on nectar of unidentified flowers. The natural reservoir for Hendra virus is believed to be flying foxes (bats of the genus Pteropus) found in Australia....

In 1994, a newly described virus, initially called equine morbillivirus, killed 13 horses and a trainer in Hendra, a suburb of Brisbane, Australia. The reservoir was subsequently identified as flying foxes (Figure), bats of the genus Pteropus (Greek pteron [“wing”] + pous [“foot”]). In 1999, scientists investigated reports of febrile encephalitis and respiratory illness among workers exposed to pigs in Malaysia and Singapore. (The pigs were believed to have consumed partially eaten fruit discarded by bats.)

The causative agent was determined to be closely related to Hendra virus and was later named for the Malaysian village of Kampung Sungai Nipah. The 2 viruses were combined into the genus Henipavirus, in the family Paramyxoviridae. Three additional species of Henipavirus—Cedar virus, Ghanaian bat virus, and Mojiang virus—have since been described, but none is known to cause human disease. Outbreaks of Nipah virus occur almost annually in India and Bangladesh, but Pteropus bats can be found throughout the tropics and subtropics, and henipaviruses have been isolated from them in Central and South America, Asia, Oceania, and East Africa.