Reassortment of Swine H1N2 and Pandemic H1N1 in Pigs, United States

The pandemic H1N1 (pan-H1N1) influenza virus was first reported in Mexico in April 2009 and soon spread to various countries (1). Although the origin of pan-H1N1 in 2009 is unknown, this virus is genetically closely related to the triple reassortant (TR) swine influenza virus (SIV) currently prevailing in pigs. Classical H1N1 SIV has been widely reported since the first influenza-like epidemic in the United States (US) pigs when a devastating human influenza pandemic occurred in 1918 (2).

Thus, in 2006 there are naturally two distinct descendant lines of H1N1 virus in 1918 and two additional rearrangement lines. Like the human H1N1 virus, the reshaped human H3N2 virus line resulted in porcine H3N2 lineage. However, none of the descendants of these viruses are close to the virulence of the mother 's virus in 1918. Clearly, the porcine H1N1 and H3N2 strains often do not infect humans, but human H1N1 and H3N2 virus significantly reduced disease and mortality compared to 1918 virus. In fact, the current death rate of H1N1 influenza is even lower than that of the H3N2 lineage (from 1968 to the present). H1N1 virus derived from strain 1918, and

Some diseases such as H1N1 (swine flu) and avian influenza may infect humans from animals. These "zoonosis common infections" are likely to become an epidemic disease. Experts believe that the outbreak of influenza A (H1N1) is caused by the overcrowding of pigs on the factory farm and the storage of waste in the huge fecal lagoon.

In recent years, cases related to swine influenza have increased significantly in the UK. Swine influenza (or swine influenza) is a respiratory disease caused by influenza virus (H1N1 virus) that infects the respiratory tract of pigs and causes persistent nasal secretion, loss of appetite, squeaky cough, and inconspicuous behavior. The World Health Organization announced that this virus is affecting the disease process as an epidemic (June 2009) and was declared late this year (August 2010) later this year. As of 2009, in England 400 people died due to the occurrence of disease. Later, in 2010, approximately 88 million doses of H1N1 vaccine were offered to a specific priority group in the UK (especially the UK). In children younger than 5 years, the incidence and morbidity of this disease has been observed to be higher