Ross River Virus

(an Alphavirus, part of the Togaviridae family)

Description: positive sense, single-stranded RNA. Non-segmented and enveloped.

Power: not very much. Only 25-24% of those infected develop symptoms, which aren’t very serious and include: headache, fever, chills, and aching in the joints and muscles. In more sever cases, polyarthritis can occur and may be recurrent for up to a couple of years.

Offenses: Unlike other diseases that cause arthritic symptoms as a result of infiltration of neutrophils in the joints, joint pain in RRV patients is caused by infiltration of monocytes and macrophages into the joint. The cytopathic effect of RRV is proliferation of the nuclear membrane, however, the symptoms that result from infection are largely immune-mediated.

Defenses: There are no defenses against the virus itself. The only treatment is the use anti-pyretic and anti-inflammatory drugs to treat the symptoms. Flare-ups of the symptoms will occur periodically, with less intensity each time, until the body is able to mount a full response, which may take as long as a year.

Strategy: to ensure survival, target female Culex annulirostris mosquitoes in the Queensland province of Australia during the months of February-May when the rivers are flooding and mosquito populations are large.