More rain means more mozzies. Protect yourself.

Anyone who lives in Australia – particularly if you work outdoors – is fully aware of the presence of mosquitoes. For most people getting bitten is a short-lived pain but in some cases one bite can lead to a significant illness and in rare cases in Australia, death.

This week (14 March), after 18 confirmed cases of Japanese encephalitis virus (JEV) in Australia and sadly two deaths, the Department of Health has declared the virus a Communicable Disease Incident of National Significance.

Professor Scott Ritchie (Adjunct), James Cook University, is an entomologist based in Cairns and has conducted studies in the Torres Strait into the mosquito that spreads JEV. We asked him what the emergence of this virus in southern states means and what we can all do to protect ourselves from this and other mosquito borne diseases while we’re out in the field.

“We’ve all seen a lot of rain recently and that means a lot more mosquitoes able to spread viruses like Ross River and Barmah Forest virus,” said Scott.

“I wouldn’t rule out that Japanese encephalitis virus is out there too and everyone should be aware and taking precautions, particularly if you live west of the Dividing Range, which is where cases are currently being detected.

“We’ve seen JEV in Australia before but only in the far north, this outbreak is a new event and at the moment there is a lot more that we don’t know than we do know.

“We do know that waterbirds (herons and egrets) are the natural host and that pigs are an amplifying host, and we’re seeing the virus in domestic pigs and piggeries. There is currently no evidence of the virus in feral pigs.

“My advice is, follow all health advisories and take precautions. This mosquito that carries JEV – Culex annulirostris – bites at night and is most active between dusk and dawn. If you’re going camping or fishing, or working outside at those times, and that means wearing long sleeves and pants and  loading yourself up with strong repellent – do it.

“But the good news is this virus outbreak is seasonal. We expect to see more cases of JEV during March and April, maybe into May, but hopefully not after that, and by then we should know more than we do now.”

About Japanese encephalitis virus (JEV)

• JEV is endemic in much of Asia and parts of the Pacific.
• JEV spreads by mosquitoes carrying it from either pigs or water birds, but it doesn’t transmit from animal to animal, or animal to human, or human to human.
• Anyone with symptoms like fever, headache, confusion or seizures should see a doctor, especially if they have been exposed to mosquitoes in at-risk areas
• Symptoms, if they are to occur, usually develop 5 to 15 days after being bitten by infected mosquitoes.
• JEV is a vaccine-preventable disease and are recommended for people at risk of exposure to the virus, as advised by your local public health authority.
• If you suspect an animal is showing signs of the disease, contact your local veterinarian or the national Emergency Animal Disease Watch Hotline on 1800 675 888.