H3N8 AI virus: A novel H9N2-original reassortment virus
H3N8 is the most prevalent subtype of equine influenza (EIV) virus, which is a serious and highly infectious disease in horses. It was also been found that it can infect dogs, cats, and harbor seals. Moreover, many recent studies have suggested that H3N8 could be transmitted between mammals and pose a threat to humans. The hemagglutinin (HA) gene was clustered into the H3 Eurasian linage and grouped with the wild birds-origin virus, whereas its neuraminidase (NA) gene belongs to the N8 North American linage and is derived from the wild bird AIVs as well. The phylogenetic analyses of internal genes demonstrated that all the internal genes of human H3N8 isolate derived from the H9N2 avian influenza virus from the poultry of China.
According to the genetic analysis, it is indicated that this H3N8 virus is a novel reassortment virus with internal gene fragments derived from the H9N2 strain, the same as the emerging human H7N9, H10N8, and H10N3 virus before. The A(H9N2) is the most commonly detected non-notifiable subtype of influenza virus in poultry and migratory birds in Asia, the Middle East, and Africa.
Will the influenza A(H3N8) cause a major public health threat?
