HEALTH officials are warning tourists to get immunised against the deadly Japanese encephalitis virus and take precautions against other diseases if they plan to travel out of the territory. The appeal was made yesterday by the Department of Health's Chief Port Health Officer, Dr Mak Kwok-hang. 'Travellers are strongly advised to observe personal and food hygiene at all time. They should take extra precautions in choosing their food and drinks,' Dr Mak said. Japanese encephalitis, a mosquito-borne disease which causes inflammation of the brain, was contracted by a 60-year-old Swedish woman visiting Bali last month. British and Hong Kong doctors recommend vaccinations for tourists visiting the tropical island. About 25 per cent of victims die, and of those who survive 80 per cent suffer various degrees of neurological disability, brain damage, deafness, blindness, or paralysis, Asia Pacific Travel Health Association chairman, Dr John Simon, said. 'I would not recommend that anyone cancel their holidays, but if you do go, get immunised at least a month in advance. 'The risk of contracting it is very small, but it is a risk.' Recently, 200 Japanese returning from Bali were confirmed to be suffering from cholera. Indonesia denied the disease existed in Bali, and tourists of other nationalities apparently were not affected. More than 9,000 Japanese cancelled trips in February. Travel industry specialists in Hong Kong and Bali said they did not notice a drop in bookings to Bali by Hong Kong tourists after reports of the diseases were made public. 'There is a big difference between one or two cases and an outbreak,' legislator Howard Young said.