Upolu virus was first isolated in 1966 from adult Ornithodoros capensis ticks that infested a sooty tern (Sterna fuscata) colony on Upolu Cay, a small atoll that is part of the Great Barrier Reef, Australia.
For a long time, Upolu Virus was thought to be an unassigned virus in the family Bunyaviridae. Antibodies have later been found in cattle and kangaroo on the Australian mainland.
Which means that the ever expanding family of Influenza-related viruses has two new members. A curious fact is that Upolu Virus and Aransas Bay Virus were discovered half a world apart. One possible explanation for this extensive distribution of this family of viruses associated with Ornithodoros capensis ticks is the fact that many of its primary hosts, such as terns, migrate for great distances.
As yet, there are no reports that Upolu Virus is capable of causing disease in humans.
 Doherty et al: Isolation of viruses from Ornithodoros capensis Neumann from a tern colony on the Great Barrier Reef, North Queensland in Australian Journal of Science - 1968
 Briese et al: Upolu virus and Aransas Bay virus, two presumptive bunyaviruses, are novel members of the family Orthomyxoviridae in Journal of Virology - 2014