Cambodian health officials on Sunday called an end to their search for a Canadian national who was possibly exposed to the influenza A (H1N1) swine flu virus after failing to find the man. Sok Touch, director of the Communicable Diseases Control Department at the Ministry of Health, said that since the man had reported no symptoms after a week, he was unlikely to have been infected by the disease. He said the Canadian arrived at Phnom Penh International Airport on May 31 and that health officials have been on his trail because of fears he may have contracted the virus from an infected 8-year-old Taiwanese boy who sat next to him on the flight.