Barma virus

Barmah Forest virus causes inflammation and joint pain and has similar symptoms to Ross River virus infection epidemic polyarthritis , but usually lasts for a shorter duration. The symptoms may include fever, headache, tiredness, painful joints, joint swelling, muscle tenderness, and skin rashes. Some people, especially children, may become infected without showing any symptoms.

The initial fever and discomfort only lasts a few days but some people may experience joint pain, tiredness and muscle tenderness for up to six months. Most people can return to work within a few days of becoming ill, although joint and muscle pain may cause some longer term restrictions in some occupations. The virus is passed to humans by the bite of an infected mosquito. It cannot be passed directly between humans. Eradication programs are the most effective way to prevent spread, however, wetland mosquitoes can fly up to 20 kilometres from their breeding grounds, potentially making this difficult SA DoH a; QLD DoH ; Webb This site complies with the HONcode standard for trustworthy health information: Verify here.

Log In Join Ausmed. Start my Subscription. Log In. Sign Up. Online CPD Articles. Barmah Forest Virus Infection. Document 2m of CPD. Spread of Barmah Forest Virus While the virus was first isolated in Culex annulirostris mosquitoes common banded mosquito , it has also been found in others species including Aedes vigilax northern salt marsh mosquito , Aedes camptorhynchus southern salt marsh mosquito and Culicoides marksi Culicoides biting midges.

The virus is found in mosquitoes at different times of the year and the level of virus in mosquitoes varies from year to year.

Warm, wet weather encourages mosquito breeding and increases the risk of infection. Most human cases occur during March and April when a higher proportion of mosquitoes carry the virus.

Although coastal areas of northern NSW have the highest rates of infection, cases can also occur inland. There is currently no vaccine against Barmah Forest virus. To protect against mosquitoes and reduce the risk of diseases they transmit:. Your doctor can take a blood sample and have it tested for antibodies against Barmah Forest virus. While a single test that measures IgM antibody can give some indication of a recent infection, this test is often falsely positive and does not necessarily indicate Barmah Forest virus infection.

A second specimen taken 14 days later is recommended to confirm a recent infection. Your doctor will be able to advise you on treating the symptoms, which may include anti-inflammatory medications. More specific testing modalities are now reasonably readily available including a confirmatory neutralizing antibody assay and real time RT-PCR 5 , Alphaviruses including Barmah Forest virus disseminate via the blood stream to the liver, spleen, muscle and lymph nodes which are the primary sites replication following inoculation from the bite of an infected mosquito 1.

The majority of studies on pathogenesis have been in the closely related alphaviral infections of Ross River virus and Chikungunya virus, with the predominant mechanism of joint manifestations proposed to be due to the release of proinflammatory mediators predominantly IL-6, IL-1, chemokine ligand 2 CCL2 and monocyte chemotactic protein-1 MCP-1 6 , 7 , More recent studies in RRV indicate that alphaviral infection may infect osteoblasts and induce bone loss 7.

Non steroidal anti-inflammatory drugs and paracetamol acetaminophen are widely used for symptomatic relief. Prevention is based on mosquito avoidance measures, particularly the use of repellants at dusk and dawn.

Molecular mechanisms involved in the pathogenesis of alphavirus-induced arthritis. BioMed research international. Hindawi Publishing Corporation; The Medical journal of Australia. Boyd A, Kay B. Assessment of the potential of dogs and cats as urban reservoirs of Ross River and Barmah Forest Viruses.

Australian veterinary journal. Wiley Online Library; ;—6. Journal of medical entomology. BioOne; ;—3. Department of Health and Aging. Commun Dis Intell Q Rep. Viral Immunology ;— Arthritogenic alphaviral infection perturbs osteoblast function and triggers pathologic bone loss. Proceedings of the National Academy of Sciences. National Acad Sciences; ;—5.