Ross River Fever

What you should know when traveling to Australia


It was supposed to be a special vacation. She'd travelled far to visit Australia. She left with a souvenir from the brief trip - from a mosquito bite. Her joints ached for a few months and she just felt tired that whole time.

This was a case of Ross River Virus Disease. 

It doesn't cause much more than this. It's a disease everyone infected is expected to recover from, but some may have symptoms for a year or more.

Australia has been seeing a rise in Ross River Virus in 2015 after a wet summer. New South Wales has seen a few hundred cases in 2015, especially on the north coast, but also in Sydney. 

What does Ross River Virus cause?

Ross River Virus Disease causes ​

  • painful joints
  • swollen joints
  • muscle pain
  • fever
  • fatigue
  • rash 

Most feel better in a few weeks. Some still feel joint pain, stiffness, or fatigue for months, intermittently for possibly a year or more.

Fever is not usually notable. The rash can begin 1-10 days after joint pains begin and can continue for as long as 7-10 days. Some have lymph node swelling (in groin or armpit). Some, but not many, may feel pins and needle numbness or tenderness in their palms or soles.

Symptoms usually begin 3-11 days and up to 21 days after infection from a mosquito bite.

The disease used to be called "epidemic polyarthritis" because of the spread of joint pain (arthritis) epidemically.

Where is it found?

It is found in Australia and Papua New Guinea. It is found in various areas in Australia, especially near coasts and other waterbodies. 

It occurs throughout the year, but especially at times of flooding and heavy rains. In much of Australia, this is February- May. Risk is less over the winter in the Southern Hemisphere.

It has caused past epidemics (1979-80) in Fiji, New Caledonia, Samoa, and the Cook Islands.

Is it deadly?

Fortunately, it's not deadly.

How does it spread?

It spreads through mosquito bites. It cannot spread from person-to-person directly. There are many mosquitoes that spread this virus - including Aedes vigilax, Aedes notoscriptus, and Culex annulirostris.

How likely is it that I'll get it?

You most likely will not get this disease - even if you're in an area where people have been infected. Even if a mosquito bites you, you more likely will not get any symptoms from the bite. In fact, of people infected with Ross River Virus, most (55-75%) do not have any symptoms.

How do you prevent this?

Prevention of RRVD is prevention of mosquito bites. There is no vaccine.

To prevent transmission, wear long sleeves and pants and use mosquito repellant, particularly DEET containing mosquitoes. Use bed nets at night and use screens and closed doors and windows to keep mosquitoes out.

Is there treatment?

There is no medication that specifically treats the infection.

How do you know you have the virus?

A clinician can examine you for signs of the arthritis (swollen and painful joints) and take a history. There is also a blood test to confirm whether you have the infection (or have had the infection in the past). Antibodies however won't be positive until 1 week - and maybe not until 10 days to 2 weeks - after infection. Someone can test negative for antibodies when they have symptoms only for a few days.

What sort of virus is this?

This is an arbovirus because it is a virus spread by arthropods - mosquitoes.

This is an Alphavirus -  and is a small, enveloped, single-stranded positive-sense RNA virus.

Can other animals be infected?

Yes, actually horses in particular have been noted to be infected and have the same joint problems with the infection with potentially a slow recovery.

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