The city of Huzhou in Zhejiang province has been identified as one of the geographic origins of a new strain of H7N9 virus, according to recent research published in the Journal of Virology.

The research, conducted by Institut Pasteur of Shanghai under the Chinese Academy of Sciences, and the Huzhou Center for Disease Control and Prevention, detected influenza subtypes co-circulating among poultry in Huzhou in April, 2013, discovering that the co-circulation not only reveals that Huzhou is one of the geographic origins of the virus, but that the new strain poses a potential threat to humans.

Huzhou is located in northern Zhejiang province, adjacent to Taihu Lake, China's third-largest freshwater lake. The city has two large natural habitats for wild birds, which are believed to be breeding grounds for the H7N9 virus.