Control of Emerging and Re-Emerging Poultry Respiratory Diseases in the United States

NON-TECHNICAL SUMMARY: Develop new prevention and control strategies for poultry respiratory diseases. Respiratory diseases cause increased production costs which are ultimately passed to the consumer.

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APPROACH: Outbreaks of avian influenza have resulted in the slaughtering of 100 million chickens. People have also become ill with these avian viruses and 22 have died from complications. Infections of low pathogenic influenza viruses have resulted in the destruction of poultry flocks in Pennsylvania, Delaware, and New Jersey. These infections have resulted in the reduction of export business. Avian influenza viruses (AIVs) are not normally found in commercial chickens in the United States. However, they can be introduced into poultry from wild bird reservoirs. Wild birds harbor all 15 hemagglutinin (HA) and neuraminidase (NA) subtypes of AIVS. These birds harbor and extract virus from their intestines, with most birds being subclinical carriers. Although almost all HA and NA subtypes of influenza can infect poultry, the H5 and H7 subtypes are the most important, because these are the subtypes associated with the highly pathogenic form of AI. Only the low pathogenic form is present in wild birds, but once introduced into poultry, these low pathogenic viruses can mutate to the highly pathogenic form. Quail are more susceptible to AIVs from water fowl than are chickens. Quail may serve as intermediate host for AIVs, where the multiplication and selection for AIVs can take place. Because of the unpredictable nature of AIV, it is not prudent to allow H5 or H7 AIVs to persist in poultry. Uncontrolled low pathogenic H5 and H7 AIVs in poultry could paralyze our industry and prolong restrictions in international trade. Therefore, outbreaks of H5 or H7 AIV in commercial poultry in the U.S., outside the live bird marketing system, have been controlled through state or state/federal control programs. This project will use the RRT-PCR to monitor and subtype AIVs in water fowl as well as clinically ill back yard fowl, submitted to the Alabama State Veterinary Diagnostic Laboratory. Cloacal and tracheal samples will be taken from birds brought to local processing facilities or the diagnostic laboratory. Our proposed work will be the first such monitoring of AIVs from non-commercial poultry in our area using this new test. It will provide valuable information as to the types of AIVs that are circulating in bird populations.