Murray Valley Encephalitis Is Active In Pilbara Region

Ruzanna Harutyunyan's picture

The Department of Health is reminding people living and holidaying in the Pilbara region of WA to continue to take care against mosquito bites following further detections of mosquito-borne viruses in the Pilbara region.

Acting Medical Entomologist Susan Harrington said that the Department’s surveillance program (undertaken by The University of Western Australia) showed that Murray Valley encephalitis (MVE) and Kunjin viruses were active near several towns in the Pilbara region.

“It is unusual to detect these viruses so far into the dry season,” Ms Harrington said.

“Murray Valley encephalitis virus and Kunjin virus are both carried by mosquitoes, and while the risk of being infected and becoming unwell is low, the illnesses can be severe and people should take sensible precautions to avoid mosquito bites,” she said.

“Initial symptoms of MVE include fever, drowsiness, headache, stiff neck, nausea and dizziness and people experiencing these symptoms should seek medical advice quickly. In severe cases, people may experience fits, lapse into a coma, may be left with permanent brain damage or die.”

“In young children, fever might be the only early sign, so parents should see their doctor if concerned, and particularly if their child is drowsy, floppy, irritable, feeding poorly or is generally distressed.”

Ms Harrington said people most likely to be affected by the MVE virus were newcomers to northern regions, such as babies, young children, tourists or new employees, but anyone experiencing these symptoms should seek medical advice quickly.

“Infection with Kunjin virus can cause symptoms that are similar to Ross River virus disease, such as swollen and aching joints, fever and rash. However in rare cases, Kunjin like MVE, can cause more severe symptoms which include headache, neck stiffness, fever, delirium and coma,” she said.


“Over 20 cases of Ross River and Barmah Forest viruses have also been reported from the Pilbara in the past three months, indicating that mosquitoes are still carrying these viruses.

“There are no specific cures or vaccines for MVE, Kunjin, Ross River or Barmah Forest viruses so it is very important that people take care to prevent being bitten by mosquitoes.”

The warning particularly applies to people living, visiting or camping near swamp and river systems during the evening and night through the Pilbara region.

People do not need to alter their plans to visit the Pilbara region, but it is important to avoid mosquito bites by taking a few simple steps, such as:

* avoiding outdoor exposure from dusk and at night

* wearing protective (long, loose-fitting) clothing when outdoors

* using a personal repellent containing diethyl toluamide (DEET) or picaridin. The most effective and long-lasting formulations are lotions or gels. Most natural or organic repellents are not as effective as DEET or picaridin

* ensuring insect screens are installed and completely mosquito-proof: use mosquito nets and mosquito-proof tents

* ensuring infants and children are adequately protected against mosquito bites, preferably with suitable clothing, bed nets or other forms of insect screening