The virus can survive in organic material, making disinfectants ineffective. manure, dirt, egg material, nasal secretions, etc.) by scraping, followed by cleaning with water and soap/detergent. For disinfection of poultry premises, it is important to first remove the organic material (i.e. However, organic matter, low temperature, and high humidity can increase its ability to survive outside a host. The unprotected virus is fairly fragile in the environment. Environmental Protection Agency has a published list of disinfectants with labeled claims to be effective against Avian Influenza: Susceptibility of the agentĪvian influenza viruses are RNA viruses with a lipid envelope which is susceptible to inactivation by most common disinfectants. Pigs are proposed to be a "mixing" vessel for co-infection with bird and mammal influenza viruses, with the potential to develop a new reasserted strain that could infect people. Other mammals can also become infected with avian influenza viruses including pigs, cats, dogs, seals, tigers, and leopards. There are rare reports of limited human infection with H5 and H7 avian influenza subtypes in Asia, Africa, and Europe, in which people with direct contact with infected poultry developed respiratory illness and fever, some of which resulted in hospitalization and deaths. All other avian influenza strains are classified as LPAI strains, which generally have milder clinical signs such as respiratory disease, conjunctivitis, and reduced egg production. The H5 and H7 subtypes are of greatest concern because they can mutate to the HPAI form, which can cause mortality up to 100% within 24 to 48 hours in susceptible birds. There are currently 16 HA subtypes and 9 NA subtypes known to infect avian species, with 144 possible HA/NA combinations that could affect birds. Influenza A viruses are typically classified based on proteins on the surface of the virus, called hemagglutinin (HA) and neuraminidase (NA). EtiologyĪvian influenza viruses belong to the Orthomyxoviridae family of RNA viruses. The indirect cost of the economic loss to the commercial industry was estimated at $3.3 billion or more. Direct cost estimates related to disease response activities of poultry depopulation, disposal, virus elimination, testing, and indemnity payments were close to $1 billion making this HPAI outbreak the most expensive U.S. The commercial turkey industry in Minnesota and egg-laying chicken companies in Iowa were most affected 7.4 million turkeys and 43 million layers died from the disease or were depopulated to contain the disease. and spread to commercial premises in 21 states. The outbreak began in captive wild birds and backyard flocks in the northwestern U.S. HPAI outbreak that occurred from Decemto June 16, 2015, was the country's largest and most significant animal health emergency ever recorded. The HPAI strains can spread very quickly, are highly contagious, and can result in poultry quarantine areas and international trade bans for the U.S., especially if commercial poultry flocks become infected. General avian influenza is often referred to as "bird flu" by the general public. When the virus is transmitted to naïve, domestic poultry, especially chickens and turkeys, some LPAI strains can mutate to the HPAI form and cause more serious clinical signs and high mortality. Various LPAI strains are known to be carried by wild waterfowl and shorebirds, which are typically asymptomatic. There are two main categories of avian influenza A viruses: Low Pathogenicity Avian Influenza (LPAI) and Highly Pathogenic Avian Influenza (HPAI).
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