What is the Ross River Virus?

The Ross River virus is a mosquito-borne disease in which mosquitos pick up the virus from wild rodents, kangaroos, and (possibly) other marsupials, then pass it to humans through a bite. However, the Ross River virus is only spread by mosquitos—one person cannot spread it to another. That being said, if someone is bitten by an infected mosquito, those in their party are also at risk of being bitten.

The Ross River virus is named after the site where it was first identified—the Ross River in Townsville, north Queensland. Interestingly, while the virus wasn’t named until the late 1950s, the disease it causes, epidemic polyarthritis, was named almost half a century beforehand.

Symptoms of the Ross River Virus

The tricky thing about the Ross River virus is that those infected often feel fine and don’t display any symptoms. About 30% of infected individuals develop symptoms, which can vary in intensity and usually occur 7-10 days after being bitten by an infected mosquito. Possible symptoms of the Ross River virus include:

• Chills
• Fever
• Rash on the limbs and trunk (although the rash’s appearance can depend on the person)
• Joint pain, stiffness or swelling (especially in the morning, most often in the fingers, wrists, ankles, and knees)
• Muscle and tendon pain
• Tiredness
• Headaches
• Swollen lymph nodes
  
  

Most people recover fully after a few weeks, though some have symptoms for several months such as joint pain and tiredness. Children often have no or milder symptoms than adults.

To find out if you have Ross River virus, 2 blood tests comparing antibody levels are taken by your doctor 2 weeks apart. Doing so will allow to determine whether the infection is recent. In many countries Ross River virus is a notifiable disease, meaning local public health authorities have to be notified. They might try to contact you to find out where you were infected with Ross River virus.

Ross River Virus Risk Zones

While the Ross River virus originated in Townsville, north Queensland, it is now found in most regions of Australia, including regional Victoria. The tropical areas of Queensland, Northern Territory and Western Australia are more commonly affected. It is particularly common around inland waterways and coastal areas and infections peak between February and May.

Ross River virus can also occur in Papua New Guinea, parts of Indonesia, and some cases have been identified in western South Pacific islands such as Fiji, New Caledonia, American Samoa, and Cook Islands. 

Epidemics of the Ross River virus occur from time to time, especially when there has been flooding, heavy rainfall, high temperatures, or high tides, as all these conditions encourage mosquito breeding—the more mosquitos there are, the more likely you are to be bitten by an infected one.

Treating the Ross River Virus 

While no medication is available to treat the Ross River virus, rest, fluids, and over-the-counter pain medications can help relieve the symptoms if you have any.

In some cases, those infected with the Ross River virus may need to be hospitalized to receive intravenous fluids and supportive care for fevers or pain.

Most people who have the Ross River virus recover within 3 to 6 months, some even within 6 weeks. Scientists believe that, over time, the body builds its immune response to the virus, eradicating it from your body and protecting you from becoming infected again. 

In about 2% symptoms may last longer than a year or recur, but this can also be due to other causes. If you’re concerned about ongoing symptoms, it’s best to check with your doctor. 

How to Protect Yourself from the Ross River Virus

Unfortunately, no preventative vaccine is available to protect from the Ross River virus; the only way to protect yourself while in the Ross River virus’s risk zones is by preventing mosquito bites.

Some ways to prevent mosquito bites include:

• Using mosquito repellents containing DEET, picaridin, or other insect-repelling active ingredients on exposed skin.
• Wearing long, loose-fitting clothes and covered shoes while outdoors.
• Limiting outdoor activity if you’re in an area with many mosquitoes around, especially at dawn and dusk.
• Covering all windows, vents, and doors.
• Sleeping underneath mosquito nets treated with insecticide if you’re sleeping out in the open or in an untreated tent.
• Emptying pots and containers around your property to remove stagnant water.