Thousands of restaurants will be inspected in the next three weeks after 11 people were infected with cholera within a fortnight. The blitz, which involves more than 9,000 restaurants, cooked food stores and other premises, comes after four patients were found to have eaten at different restaurants. Deputy director of the Department of Health Dr Paul Saw Thian-aun said the two municipal councils would complete the inspection of all Category B and C restaurants in three weeks. Food premises are divided into satisfactory, acceptable and poor for hygiene conditions, with categorisations of A, B and C respectively. A department consultant doctor, Mak Kwok-hang, said hygiene conditions in the four restaurants some victims ate in were unfavourable. 'Initial inspection showed poor hygiene conditions at the restaurants - cockroaches were found, cooked food was put on the floor and there was no soap in the staff toilets,' he said. The other victims caught the disease at home where food was inadequately reheated and seafood inadequately cooked. Of the 11 confirmed cholera cases reported between late July and last Sunday, 10 were local cases involving patients aged between 22 and 87. All but two women and a man have been treated and discharged. The imported case of a 21-year-old woman who visited Shekou during the incubation period was also discharged. Dr Saw said the latest outbreak appeared to be under control as no new cases had been reported in the past three days. 'However, we should remain vigilant because the current hot and humid weather provides optimum conditions for the growth of bacteria,' he said. The World Health Organisation told the department yesterday to strengthen its preparedness against cholera in view of the extremely heavy rainfall and floods this year. The outbreak brings this year's total to 36 imported and 28 local cases, compared with 14 in total last year.