Screwworms Once Again Eradicated from the U.S.
March 24, 2017

The U.S. Department of Agriculture's Animal and Plant Health Inspection Service announced the successful eradication of the New World screwworm from Florida.

Animal health checkpoints, or interdiction stations, were closed on Saturday. The last sterile fly releases in Homestead, Fla., took place on Tuesday and fly releases are scheduled to end on April 25 in the Florida Keys.

APHIS considers an area to be screwworm-free through surveillance, which includes trapping flies and visually inspecting animals for signs and symptoms of NWS infestation. No new cases of NWS have been reported in Florida since Jan. 10. Science shows that, when sterile flies are released, elimination of NWS is achieved three life cycles after the last detection. The flies have on average, a 21-day life cycle, and they continue to circulate in the area for three weeks beyond each release. In the Keys, APHIS will complete five life cycles beyond the last positive screwworm detection. Out of an abundance of caution, APHIS also released flies in the Homestead area for three completed life cycles.