Screwworm – what happens now?

Jules Bernstein University of California
Jun 8, 2026
Jun 8, 2026

1 of 2

A flesh-eating fly has returned to the United States. What now?

University of California

New World screwworm larvae will burrow into wounds on warm-blooded animals.

USDA

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Jules Bernstein University of California

The New World screwworm lays its eggs in open wounds and burrows into skin. While human infections are rare, the insect poses an existential threat to cattle farming and dairy production. And it has returned to the United States.

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