WHAT IS HIGH PATHOGENICITY AVIAN INFLUENZA H5N1?
There are numerous different strains of avian influenza, but only a very few of these are a serious health concern for animals or people. Most strains circulate in wild birds, especially waterbirds, at low levels, and at worst cause only mild disease. These ‘Low Pathogenicity Avian Influenza’ (LPAI) viruses also have only mild effects on poultry. In contrast, some variants of the H5 and H7 ‘subtypes’ can cause massive mortality in poultry. These are designated ‘High Pathogenicity Avian Influenza’ (HPAI). HPAI viruses do not normally occur in wild birds. They arise in poultry, where intensive rearing and crowded conditions allow the virus to evolve to a highly pathogenic form. Hence HPAI is also called ‘poultry flu’. Wild birds can also be infected with, and killed by, HPAI viruses. They appear to acquire the virus through contact with infected poultry or with facilities used by them. The H5N1 virus currently circulating is a High Pathogenicity Avian Influenza (HPAI). This strain of the
There are numerous different strains of avian influenza, but only a very few of these are a serious health concern for animals or people. Most strains circulate in wild birds, especially waterbirds, at low levels, and at worst cause only mild disease. These Low Pathogenicity Avian Influenza (LPAI) viruses also have only mild effects on poultry. In contrast, some variants of the H5 and H7 subtypes can cause massive mortality in poultry. These are designated High Pathogenicity Avian Influenza (HPAI). HPAI viruses do not normally occur in wild birds. They arise in poultry, where intensive rearing and crowded conditions allow the virus to evolve to a highly pathogenic form. Hence HPAI is also called poultry flu. Wild birds can also be infected with, and killed by, HPAI viruses. They appear to acquire the virus through contact with infected poultry or contaminated feed, litter or water. The H5N1 virus currently circulating is a High Pathogenicity Avian Influenza (HPAI). This strain of the v
