Are You Familiar With the Risks of Ross River Virus Infection?
Published: 13 December 2023
Published: 13 December 2023
Ross River virus infection is Australia's most common mosquito-borne infection (Healthdirect 2023).
Ross River virus (RRV) infection, also known as Ross River fever or epidemic polyarthritis, is endemic in Australia, Papua New Guinea, parts of Indonesia, and several islands in the South Pacific (NT.GOV.AU 2023).
The largest outbreak in Australia occurred in 2015, with over 9,000 cases notified, more than 6,000 of them from Queensland (DoHaAC 2023). Such epidemics relate to favorable mosquito breeding conditions such as heavy rainfall, floods, high tides, and high temperatures (Murphy et al. 2020).
Since 2015, there have been at least 2,000 cases of RRV infection in Australia every year, with most occurring in Queensland (DoHaAC 2023).
Of the more than 40 species of mosquito (Queensland Health 2017) that have been found to be capable of carrying the virus, the most significant are:
(NT.GOV.AU 2023; Wildlife Health Australia 2015)
Mosquitoes are believed to pick up RRV from kangaroos, wallabies, possums, wombats, wild rodents, birds, flying foxes, dogs, horses, cattle, and possibly humans (Murphy et al. 2020; Skinner et al. 2019). The virus enters the bloodstream through saliva from an infected mosquito, reproduces in red cells, and then in muscles, joints, and skin (ABC Health 2015).
RRV cannot be directly spread from person to person (Healthdirect 2023).
Many of those bitten by an infected mosquito do not develop any symptoms. This is especially true of children, who generally only experience mild symptoms that last for a shorter length of time, if any (NT.GOV.AU 2023).
Most cases are in adults aged 30 to 64 years (Murphy et al. 2020). The incubation period is usually 7 to 14 days, but symptoms can develop anywhere between 3 and 21 days after being bitten (NT.GOV.AU 2023).
The first symptoms of RRV infection are typically severe pain in multiple joints (usually the wrists, knees, ankles, and fingers) and stiffness (NT.GOV.AU 2023; NSW Health 2022).
Other symptoms may include:
(NT.GOV.AU 2023; NSW Health 2022)
Symptoms usually resolve within six weeks, but in some cases, they may last for months or even up to one or two years. In about 10% of cases, people will experience ongoing depression and fatigue (SA Health 2022). In most cases, getting RRV once should guarantee lifelong immunity, although there have been a few instances of reinfection (NT.GOV.AU 2023).
RRV infection is diagnosed via blood tests to detect antibodies. Typically, there will be one blood test undertaken when the patient is unwell and another two weeks later. This will allow the two test results to be compared (Healthdirect 2023).
It may be necessary to eliminate other causes of similar symptoms, such as dengue, Barmah Forest virus, chikungunya, rubella, influenza, and rheumatoid arthritis (Farmer & Suhrbier 2019).
Treatment is non-specific. Anti-inflammatories such as ibuprofen, paracetamol, and aspirin (not for children under the age of 12) may provide effective relief of symptoms (Healthdirect 2023; NT.GOV.AU 2023).
A combination of rest, exercise, and a healthy diet is also important (Healthdirect 2023). Stress, fatigue, and alcohol can exacerbate symptoms (NT.GOV.AU 2023).
Protect yourself from mosquito bites by:
(Queensland Government 2017)