The following background on Barmah Forest Disease in Australia is abstracted from Gideon www.GideonOnline.com and the Gideon e-book series. [1,2]
Barmah Forest disease virus was first isolated from mosquitoes (Culex annulirostris) in the Barmah Forest, Northern Victoria in 1974. Human infection was subsequently reported along the south coast of New South Wales during the mid-1980’s; in Queensland during 1988 to 1989; in the Northern Territory in 1992 ; and in southwestern Western Australia in 1993. A new focus was described in Gippsland (Victoria) during 1993 to 1994. The number of localities reporting Barmah Forest Disease increased during 1996 to 1998, and again during 1999 to 2001.
Disease incidence has increased somewhat since 2000, with most cases reported from Queensland and New South Wales. In the following chart, I have contrasted incidence data for Barmah Forest disease with those of a similar illness, Ross River disease 
6.5% of healthy adults in Queensland.
11.3% of horses in Brisbane, 1.2% of dogs, 10.7% of bushtail possum (Trichosaurus volpecula) , 1.5% of cats, 0% of flying foxes (1977 to 1999) 8
– The known vectors are Ochlerotatus vigilax, Culex annulirostris, Ae. (Oc.) camptorhynchus, Ae. normanensis and Coquillettidia species.
– Aedes notoscriptus is considered an additional potential vector.
– BFD virus has also been recovered from Aedes vigilax in eastern Australia (2005 to 2008)
Wallabies and kangaroos serve as reservoirs for the virus; however, antibody is also present in cattle and horses.
– Similar local illnesses have been ascribed to Trubanaman and Gan Gan viruses (Bunyaviridae); and Kokobera, Stratford and Edge Hill viruses (Flaviviridae).
– A single human case of Edge Hill virus infection has been described.
– A case of Kokobera fever was reported from Darwin in 1998.
– Kokobera virus has been isolated from Culex annulirostris in the Northern Territory and northern Queensland.
– Kokobera virus was isolated from 18 of 25,351 Cx. annulirostris tested in Cape York in 1998.
1992 to 1994 – An outbreak (22 cases) of Barmah Forest disease was reported in the south-west of Western Australia.
1995 – An outbreak (135 cases) was reported along the south coast of New South Wales.
2002 – An outbreak (47 cases) was reported in Victoria.
2002 to 2003 – An outbreak (297 cases) was reported in Queensland.
2005 to 2006 – An outbreak (1,895 cases) was reported.
1. Berger SA. Infectious Diseases of Australia, 2013. 540 pages, 162 graphs, 3364 references. http://www.gideononline.com/ebooks/country/infectious-diseases-of-australia/
2. Berger SA. Australo-Pacific Arboviruses: Global Status, 2013. 32 pages, 20 graphs, 307 references. http://www.gideononline.com/ebooks/disease/australo-pacific-arboviruses-global-status/
3. Gideon Graph Tool, see tutorial at http://www.GIDEONonline.com/wp/wp-content/uploads/Gideon-Graphs.pps
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