NSW mosquito virus capable of causing convulsions and lifelong neurological damage

A mosquito virus that can cause seizures and lifelong neurological damage has been detected in New South Wales for the first time in more than a decade.

Murray Valley Encephalitis Virus (MVE) was detected in a mosquito in Menindee, in the far west of New South Wales.

Locals have been urged to take steps to protect themselves from the virus, which is transmitted from infected animals to humans by mosquitoes.

In some cases, it can cause severe neurological problems, with symptoms including headaches, seizures, and loss of consciousness.

The last time MVE was detected in NSW was in 2011.

Rains, floods and summer heat have created the perfect environment for disease-carrying mosquitoes to thrive, health authorities warn.

Mosquitoes transmit the virus to humans through infected animals such as waterfowl such as herons and egrets.

The disease cannot be transmitted from one human to another, and people cannot contract the virus by touching an infected animal or eating animal products.

Many people infected with Murray Valley Encephalitis do not experience any symptoms, although some will develop a severe infection and the virus can cause neurological problems in rare cases, Health Protection NSW chief executive Richard Broome said.

“Only a small proportion of people infected with the virus will experience symptoms, including fever, headache, nausea, vomiting, loss of appetite, diarrhea and muscle aches,” Dr Broome said.

“Among those who do get a serious infection, some may die or have lifelong neurological complications.”

There are no vaccines or specific treatments for Murray Valley Encephalitis, and the best way to avoid infection is to avoid being bitten.

“Avoiding mosquito bites will also protect against other mosquito-borne infections, such as Japanese encephalitis, Ross River fever and Barmah Forest virus,” said Dr Broome.

It comes as mosquitoes that carry Ross River fever and Barmah Forest virus are detected five times more than usual in South Australia, SA Health said on Wednesday.

The authority has also detected extremely high numbers of a species of mosquito known to transmit a number of serious diseases, including Japanese encephalitis, Murray Valley encephalitis and Kunjin/West Nile virus.

The virus can cause flu-like symptoms or even death and can only be spread through mosquito bites, NSW Health says the best protection is not to get bitten (pictured, file image)

SA Health detected the mosquitoes in the Mallee region, west of Adelaide.

Vaccines are available for Japanese encephalitis, but not for the other infections.

SA health director Nicola Spurrier echoed Dr Broome’s comments, saying it was vital that people work to protect themselves against mosquito bites.

“We have an explosion in mosquito populations right now, so it’s vital that South Australians protect themselves,” he said.

Some 45 people have contracted Japanese encephalitis in Australia since January 2021, according to the most recent government data.

They include 35 definite cases and 10 probable cases, in all states and territories except Tasmania and WA.

The virus is a rare but serious mosquito-borne disease that can also infect animals.

A small number of infected people, about one in 250, will develop inflammation of the brain, which can cause permanent nervous system damage or death.