A 49-year-old Yuen Long woman is fighting for her life after being infected with what is believed to be Japanese encephalitis.

She was admitted to Tuen Mun Hospital on May 25 with symptoms of vomiting, fever and convulsions. Her condition is critical. Tests are being conducted to confirm her illness.

As a precautionary measure, the Food & Environmental Hygiene and Agriculture, Fisheries & Conservation Departments have conducted vector surveys and mosquito control measures around her Tai Kei Leng home. There are nine pig farms within two kilometres.

She has no recent travel history and her family members have been put under medical surveillance. They have no symptoms.