Avian influenza (AI) has been confirmed in a broiler chicken flock in Gonzales County, TX. AI viruses, which can infect chickens, turkeys, pheasants, quail, ducks, geese, and guinea fowl, as well as a wide variety of other birds, can be classified into low pathogenic and highly pathogenic strains based on the severity of the illness they cause. Most AI virus strains are low pathogenic and typically cause mild clinical signs and low mortality in infected birds. However, some low pathogenic virus strains are capable of mutating under field conditions into highly pathogenic viruses, which cause more illness and high mortality in infected birds.
Exposure of poultry to migratory waterfowl and the international movement of poultry, poultry equipment, and people pose risks for introducing highly pathogenic avian influenza (HPAI) into U.S. poultry. Once introduced, the disease can be spread from bird to bird by direct contact. HPAI viruses can also be spread by manure, equipment, vehicles, egg flats, crates, and people whose clothing or shoes have come in contact with the virus.
On February 17, 2004, routine surveillance samples taken from the Gonzales County flock and sent to the Texas Veterinary Medical Diagnostic Laboratory were identified as preliminarily positive for an H5 type AI virus. Upon learning that the flock of broilers had elevated death rates, the Texas Animal Health Commission (TAHC), in accordance with standard practice in such situations, dispatched a foreign animal disease diagnostician to collect additional samples and information from the farm. These samples were sent to the Texas State laboratory and to the U.S. Department of Agriculture's National Veterinary Services Laboratories in Ames, IA, which is the U.S. national reference laboratory for foreign animal diseases.
On February 19, 2004, test results indicated that the flock had H5N2 avian influenza. Since H5 and H7 strains can be either low pathogenic or highly pathogenic, additional tests were conducted. Genetic sequencing was completed on February 23, 2004, the results of which indicated a highly pathogenic form of AI. International standards mandate reporting these sequencing results to the Office International des Epizooties, the world animal health organization. The Department is conducting further laboratory testing to confirm the pathogenicity.
The flock of approximately 6,600 broiler chickens was depopulated. The Department and the TAHC are in the process of conducting an epidemiological investigation and surveillance testing within a 10-mile radius of the affected property.
The existence of HPAI in Texas represents a threat to the U.S. poultry and bird industries. It constitutes a real danger to the national economy and a potential serious burden on interstate and foreign commerce. The Department has reviewed the measures being taken by Texas to control and eradicate HPAI and has consulted with the appropriate State Government and Indian tribal officials in Texas. Based on such review and consultation, the Department has determined that the measures being taken by the State are inadequate to control or eradicate HPAI. Therefore, the Department has determined that an extraordinary emergency exists because of HPAI in Texas.
This declaration of extraordinary emergency authorizes the Secretary to (1) hold, seize, treat, apply other remedial actions to, destroy (including preventative slaughter), or otherwise dispose of, any animal, article, facility, or means of conveyance if the Secretary determines the action is necessary to prevent the dissemination of HPAI and (2) prohibit or restrict the movement or use within the State of Texas, or any portion of the State of Texas, of any animal or article, means of conveyance, or facility if the Secretary determines that the prohibition or restriction is necessary to prevent the dissemination of HPAI. The appropriate State Government and Indian tribal officials in Texas have been informed of these facts.
Effective Date: This declaration of extraordinary emergency shall become effective February 23, 2004.Start Signature
Ann M. Veneman,
Secretary of Agriculture.
[FR Doc. 04-4587 Filed 3-1-04; 8:45 am]
BILLING CODE 3410-34-P