There have been two epidemics of o’nyong’nyong fever. The first occurred from 1959 to 1962, spreading from Uganda to Kenya, Tanzania, Zaire (Democratic Republic of the Congo), Malawi and Mozambique, and affecting over two million people, one of the largest arbovirus epidemics ever recorded. The first virus isolates were obtained during this outbreak from mosquitoes and human blood samples collected from Gulu in northern Uganda in 1959. The second epidemic in 1996–1997 was confined to Uganda. The 35-year hiatus between the two outbreaks and evidence of an outbreak in 1904–1906 in Uganda indicate a 30–50 year cycle for epidemics. In 2013, ONNV was confirmed as the cause of disease in a 60-year-old German woman who became infected while traveling in East Africa. In 2015–2016 there was a minor outbreak in Uganda with 51 suspected cases. There has been a minor outbreak in Mombasa (Kenya) and the County Government of Mombasa issued a warning. A 2015 study indicated that ONNV is endemic in coastal East Africa, along with chikungunya virus.
O'nyong'nyong virus
Alkhurma virus
Chinese virus
GB virus C
Muju virus
Amur virus
Modoc virus
Playa de Oro virus