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The Screwworm Barrier Maintenance Program in Panama (COPEG), managed by the United States and Panamanian governments, seeks to reduce the damage caused by New World screwworms, which attack livestock and other warm-blooded mammals. The screwworm affects animal agriculture and livestock in South America, and previously affected warm-blooded mammals in North and Central America before COPEG began in the 1950s and the current barrier was established in the early 2000s.

COPEG produces millions of flies in its Panama laboratory/production facility, sterilizes these flies using cobalt, and releases them by airplane over a barrier region running through eastern Panama and neighboring areas of Colombia. Releasing millions of sterile flies reduces the possibility that a native fertile male fly will mate with a native fertile female fly, thereby reducing the fly population. The Program employs approximately 400 people and costs $15 million annually.

The Program seeks to partner with New World screwworm-free nations to maintain import protocols and quarantine processes to prevent infested animals entering from those countries. The Program also maintains field surveillance and public information campaigns in many countries. If an outbreak occurs north of the barrier region, sterile screwworm flies from the program will be released over the infested areas.




History of the Screwworm Program

USDA-Agricultural Research Service (ARS)



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