SYDNEY – The potentially fatal Japanese encephalitis virus (JEV) is continuing to seep across Australia’s flooded regions with confirmation of another case on Monday.

The JEV patient, a man in his 60s from the state of New South Wales (NSW), is the sixth case of the state, while the total infections nationally reached at least 17, including two deaths, since late February when the mosquito-borne virus was first detected in piggeries.

JEV, which can strike animals and humans and was only detected in Australia’s tropical far north, has crept into NSW, southern Queensland, Victoria and South Australia.

Although most people have virtually no symptoms, others can suffer brain infections which can cause headaches, convulsions, vomiting, disorientation and seizures.

Just how much worse the outbreak will become remains a mystery, according to Francesca Frentiu from Queensland University of Technology (QUT) School of Biomedical Sciences.

“It’s difficult to accurately project the number of future cases because we’re missing some key information,” Frentiu told Xinhua on Tuesday.

“We don’t know exactly which mosquitoes are transmitting JEV, whether native birds are acting as reservoirs, how widespread virus activity is in Australia and the potential role of feral pigs,” she said.

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Health Minister Greg Hunt said the government will spend 69 million Australian dollars (about 49.5 million U.S. dollars) for 130,000 doses of JEV vaccine.

Despite such efforts, Frentiu predicts that Australians are likely to continue to see more “exotic mosquito-borne viruses pop up in places where they never were before.”

“Climate change is leading to hotter temperatures in temperate areas and extending mosquito ranges,” she said. “Years with unusually high rainfall can also boost mosquito populations, leading to increased virus activity.”