Supported by the National Key Basic Research and Development Program of China (Grant No.2007BC109103);Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No.KSCX2-YW-N-063);National Natural Science Foundation of China (Grant No.30671576)
Subtypes of H1N1 influenza virus can be found in humans in North America,while they are also asso-ciated with the infection of swine.Characterization of the genotypes of viral strains in human popula-tions is importan...