Japanese encephalitis may have infected one in 30 people in parts of northern Victoria

Health department has expanded vaccine eligibility after a survey indicated the virus was more widespread than previously reported

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Japanese encephalitis has infected as many as one in 30 people in parts of northern Victoria, the state's health department has said, as it opened vaccine eligibility to more local government areas.

The department estimated the number in affected northern Victorian council areas, which was higher than previously thought, after a serosurvey indicated a greater number of cases than the 13 reported during last year's mosquito season.

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