Further tests are needed on a suspected patient but few details are released Health authorities were yesterday still trying to establish whether a 44-year-old woman in a serious condition at Queen Mary Hospital is suffering from Japanese encephalitis. The case has been classified as suspected 'general encephalitis', a Department of Health spokeswoman said. Results of preliminary tests would be available today but further tests would be needed to confirm the diagnosis, she added. No other details, including the woman's travel history, were released yesterday. The case has raised concern after the recent outbreak in Guangdong. A total of 290 Japanese encephalitis cases have been reported so far this year in the province, with the death toll at 24. 'Human Japanese encephalitis is rare in Hong Kong. It is transmitted by the bite of infected mosquitoes and is not directly transmitted from person to person,' the Health Department spokeswoman said. Mosquitoes pick up the Japanese encephalitis virus from infected animals, mostly domestic pigs. There were two imported cases of Japanese encephalitis in Hong Kong last year, and one in 2001. All recovered, the department said. Japanese encephalitis is a leading form of viral encephalitis in Asia, causing at least 50,000 cases of clinical disease and 10,000 deaths each year, mostly among children, according to the World Health Organisation. The viral encephalitis follows an incubation period of four to 14 days and is mostly characterised by sudden onset of fever, chills and aches, including headaches. 'In children, gastrointestinal pain and dysfunction may dominate the initial stage of the disease. Convulsions are also common in paediatric patients,' the WHO said. The confirmation of a Japanese encephalitis case could raise fears about continuing cross-border transmission of deadly diseases in the wake of Sars, which killed 298 people out of 1,755 infected. The outbreak in Guangdong has also exposed poor communication between health authorities in Hong Kong and the mainland. Hong Kong Deputy Director of Health Dr Leung Pak-yin has admitted that he learned about the outbreak only after reading press reports. The Department of Health has advised people to take precautionary measures against mosquito bites.