Agriculture Victoria said six cases have now been found in the shires of Loddon, Campaspe, Wangaratta, Gannawarra, greater Shepparton and greater Bendigo.
Detections in Gannawarra, greater Shepparton and greater Bendigo were confirmed by the Australian Centre for Disease Preparedness on the weekend.
Agriculture Victoria staff members are continuing surveillance activities and providing information and advice to farmers.
Japanese encephalitis occurs most commonly in pigs and horses and could cause reproductive losses for susceptible animal species.
Humans could be impacted by the disease if bitten by an infected mosquito.
Chief veterinary officer Graeme Cooke urged anyone who owned pigs or horses to take steps to reduce exposure to mosquitoes.
“We encourage pig farmers and horse owners to eliminate mosquito breeding grounds near their animals, such as stagnant water, to reduce the chances of them being bitten,”he said.
He also said people should protect themselves from mosquito bites by wearing long, loose fitting clothes outdoors and using effective mosquito repellents containing picaridin or DEET on all exposed skin and trying to limit outdoor activity if lots of mosquitoes are around.
People cannot be infected by eating pig meat. Pork meat or pork products are safe to consume.
Nationally agreed movement restrictions have been applied to infected pig properties to reduce the spread of the disease in pigs.
Japanese encephalitis is a notifiable disease under the Livestock Disease Control Act.
Report any cases of unexplained pig deaths, especially piglets, or unexplained horse illnesses, to the 24-hour Emergency Animal Disease Watch Hotline on 1800 675 888, to your local vet or to Agriculture Victoria animal health staff. For more information visit agriculture.vic.gov.au/je
The Department of Health has issued public health advice available at www.health.vic.gov.au/infectious_diseases/japanese-encephalitis-virus
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