Hong Kong is on high alert after a man on the mainland died from bird flu, officials said. The man, who died Saturday in neighboring Shenzhen, was infected with the same strain of bird flu that was recently found in a dead bird in Hong Kong\'s New Territories, the Wall Street Journal reported Monday. Hong Kong has suspended imports of live poultry and poultry products from parts of Shenzhen. While bird flu is primarily a threat to poultry, not humans, scientists warn that mutations in the H5N1 strain of the disease can allow human-to-human transmission. Since 2003, bird flu has infected 574 people in more than a dozen countries, Hong Kong officials said. More than half died from the illness. Dr. Leo Poon, assistant professor at the University of Hong Kong\'s school of public health, said that the overall risk of a return of an H5N1 outbreak in Hong Kong is low.