The H1N1 swine influenza virus belongs to the A type of influenza virus H1N1-M2 protein. The H1N1 swine influenza virus shares homology with many influenza virus types, including humans, birds, and many mammals, and its viral protein sequence homology is also high: H5N1H7N7H9N2H13N6H16N3N1N2N1H3N2H2N2, etc., and is still constantly mutating.
　　
The H1N1 swine influenza virus not only has high species homology, but also spreads to many countries and regions in Europe, America, Asia, including many provinces in the central and eastern parts of the United States and Southeast Asia such as Hong Kong and Thailand. Porcine transmission occurs every year, and human pig transmission has been on the rise in recent years.