A NSW man who died last month had Japanese Encephalitis, the mosquito-spread virus recently detected in the state for the first time.
NSW Health announced on Wednesday afternoon a post-mortem of the Griffith man in his 70s confirmed he had Japanese Encephalitis when he died in a Sydney hospital on February 13.
Health authorities are warning people to take precautions against mosquito bites that can transmit the disease, which can cause severe neurological illness.
Mosquitoes can infect animals and humans but it does not spread from humans to humans.
There are now three known cases of the disease in NSW, where locally acquired cases have never previously been identified.
A NSW man and a child previously confirmed with the virus are being treated in Victorian hospitals and several more are awaiting test results to confirm whether they have it.
The virus was detected in samples from pig farms across the east coast and South Australia last month.
Health authorities around the country are working to determine the circulation of the virus.
NSW Health has secured vaccines and is prioritising workers on the affected pig farms and their family members who live there.
It comes as four cases of Japanese encephalitis have been confirmed in South Australia with three people acquiring their infections locally.
Health officials recently investigated 10 people hospitalised with acute encephalitis and said four of those were now confirmed to be the Japanese variety.
Seven of those people remain in hospital. One person has died.
On Tuesday, the Victorian Department of Health revealed a man, aged in his 60s from northern Victoria, died on 28 February and an autopsy revealed the cause of death as Japanese encephalitis.
It is investigating how he contracted the virus.
