Risk factors for avian influenza virus in backyard poultry flocks and environments in Zhejiang Province, China: a cross-sectional study
Abstract Background Human infection of avian influenza virus (AIV) remains a great concern.Although live poultry markets are believed to be associated with human infections, ever more infections have been reported in rural areas with backyard poultry, especially in the fifth epidemic of H7N9.However, limited information is available on backyard pou