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Rachel Iadicicco (301) 734-3255
Angela Harless (202) 720-4623

WASHINGTON, May 15, 2008--The U.S. Department of Agriculture's Animal and Plant Health Inspection Service (APHIS) is proposing to remove screwworm-related restrictions from the importation requirements for live horses, ruminants, swine and dogs from Panama based on the eradication of screwworm in that country.

Under the proposed rule, APHIS would remove Panama from the list of regions where screwworm is considered to exist. Live animal imports would no longer have to be inspected and quarantined for screwworm.

The eradication of screwworm in Panama was the result of cooperative efforts between Panama and USDA that relied on the release of sterile adult screwworm flies. These sterile screwworm flies mate with existing flies, ensuring no offspring are produced and breeding natural screwworm populations out of existence. A permanent biological barrier in the Darien Gap region bordering the South American continent will be maintained by the continued release of sterile flies to prevent entry or reentry of screwworms from South America.

Screwworm was initially eradicated from the United States in 1966 using regular releases of sterile adult screwworm flies. Infrequent but costly outbreaks, however, continued in the United States due to the entry of screwworms from affected neighboring regions. This led to eradication programs supported by APHIS in Mexico and later the entire Central American Isthmus. The successful completion of this eradication program ended in Panama with the establishment of the permanent biological barrier, preventing the spread of screwworm back into the United States.

Screwworm is a parasite that affects mammals, including humans and birds. Screwworm larvae hatch from eggs laid by flies on host animals--often in, or adjacent to, open wounds--and feed on their flesh, causing great suffering and losses. Screwworm causes extensive damage to livestock and other warm-blooded animals. Many cases of humans being infested with screwworms have also been reported.

Notice of this proposed rule is published in the May 16 Federal Register.

Consideration will be given to comments received on or before July 15. Send two copies of postal mail or commercial delivery comments to Docket No. APHIS-2007-0141, Regulatory Analysis and Development, PPD, APHIS, Station 3A-03.8, 4700 River Road, Unit 118,

Riverdale, MD 20737-1238. Comments can be submitted on the Federal eRulemaking portal at

Comments are posted on the Web site and also can be reviewed at USDA, Room 1141, South Building, 14th Street and Independence Ave., S.W., Washington, DC, between 8 a.m. and 4:30 p.m., Monday through Friday, excluding holidays. To facilitate entry into the comment reading room, please call (202) 690-2817.



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