Surge in mosquito-borne illnesses in Vic

Victoria is experiencing a surge in mosquito-borne illnesses, many of them in areas affected by recent floods.

Almost 400 cases of Ross River virus have been recorded so far in 2011, compared to fewer than 100 cases at the same time last year.

Cases of Barmah Forest virus have jumped to close to 100, from fewer than 10 a year ago.

Victoria's chief health officer Dr John Carnie said there were cases of mosquito-borne viruses across the state, but many were in areas that had experienced recent flooding.

"We are seeing a lot of these cases from those areas that were affected by the floods," he told reporters on Tuesday.

Dr Carnie urged all Victorians to protect themselves from mosquito bites.

"We are working with councils in a number of the previously flood-affected areas to see what can be done in relation to getting rid of the large excess stagnant water that is around, but obviously everybody can play their part by looking at areas around the home," he said.

He advised people to wear long, loose-fitting clothing and use mosquito repellent.

Around the home, people should check their insect screens are in good order and get rid of any areas of stagnant water.

The Ross River and Barmah Forest viruses have the same symptoms - fatigue, rashes and muscle aches and pains - and can be diagnosed only by blood tests.

While people recover from both, Dr Carnie said sufferers felt very fatigued and could be off work for weeks or sometimes even months.

Dr Carnie said there would be a drop in mosquito-borne diseases once cold overnight temperatures arrived, limiting mosquito breeding.

South Australia has also experienced an increase in Ross River and Barmah Forest virus infections this year.

Victorian and NSW health authorities issued warnings about mosquitoes last week, after the rare and potentially fatal Murray Valley encephalitis virus was detected in chickens along the Murray River.

Dr Carnie said there had not been any humancases of the virus.