Infection with the virus often causes no symptoms, but it can lead to either an encephalitic disease or a non-encephalitic disease.[6] Non-encephalitic Kunjin virus disease can cause symptoms including acute febrile illness, headache, arthralgia, myalgia, fatigue and rash.[1][6] Kunjin virus encephalitis features acute febrile meningoencephalitis.[1]
Kunjin virus is transmitted by mosquito vectors, especially the Culex annulirostris.[3] They pass the virus to waterbird reservoir hosts; a major example is the nankeen night heron.[3] It is also passed to horses and humans.[7] The virus has been isolated in mosquitoes in South East Asia but in humans, only in Australia.[6] It has been found all over Australia and is particularly prevalent in areas near wetlands and rivers.[8]
The control of Kunjin virus is achieved in the same ways as other mosquito-borne diseases. These include individuals using insect repellent, wearing long-sleeved clothes and avoiding areas where mosquitoes are particularly prevalent.[1] Habitat control by government agencies can take the form of reducing the amount of water available for mosquitoes to breed in, and the use of insecticides.[9] There is no available vaccine against Kunjin virus.[1]