NSW Health is urging people to take extra precautions against mosquito bites after the Kunjin virus was detected in the Hunter.
Hunter New England Health's Dr David Durrheim said the virus, which can infect humans, has been found in horses across various regions.
Kunjin and Murray Valley encephalitis virus are two rare but serious infections of the brain which can cause symptoms such as severe headache, neck stiffness, sensitivity to bright lights, drowsiness, confusion and possible seizures.
"It is important to be vigilant about protecting yourself from mosquito bites as mosquitoes can spread Kunjin and Murray Valley encephalitis viruses," Dr Durrheim said.
"There is no vaccine and no specific treatment for these viruses. The best way to avoid infection is to avoid being bitten by mosquitoes."
Simple ways to avoid mosquito bites include covering up with light-coloured, loose-fitting clothing, using effective repellent and insecticides and removing water containers from outside the home.
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