A hygiene warning has been issued after a sharp increase in the number of food poisoning incidents this year, despite a drive by officials to clean up the city. The increase could be attributed to the rising number of people eating out and to falling public awareness about hygiene, according to the assistant director of the Food and Environment Hygiene Department, Thomas Chung Wai-hung. The department's warning came after several students suffered suspected food poisoning after eating in Tsim Sha Tsui last week. The latest Health Department figures reveal that so far this year, almost 1,600 people have fallen ill in 463 food poisoning cases - up 76.7 per cent on the first six months of last year. During the whole of last year, 823 cases were reported, but in 2003 - when the Sars virus hit Hong Kong, hygiene awareness was raised and fewer people dined out - about 400 cases were reported. Mr Chung said that since Sars, public awareness of hygiene had fallen and now needed to be improved. He reminded the public to maintain good 'personal, food and environmental hygiene'. Twelve students from a secondary school in Tseung Kwan O suffered mild food poisoning after eating in a Tsim Sha Tsui hotel on Monday and Tuesday. Another 16 people suffered bacterial food poisoning after eating at the Han Yang Won Korean and Thai restaurant in Chong Hing Square, Mongkok, on Tuesday. And between June 14 and 16, more than 50 people came down with suspected food poisoning after dining at a Tuen Mun hotel. One cause of the recent food poisoning incidents could be contaminated oysters, Mr Chung said. Food samples had been taken for examination but the department was still awaiting the results. Commenting on a scare in Shenzhen last week, in which two lychee farms were closed after pesticide in their fruit was found to pose an immediate health danger, Mr Chung said the department would follow up the case. Under the food surveillance system, samples of imported foods were randomly taken for examination.