New World Screwworm

Order of the State Veterinarian

New World Screwworm Restrictions On Interstate Movement Of Animals

Interstate Animal Movement Requirements

Suspected New World screwworm flies or larva should be reported to LDAF at vetreports@ldaf.state.la.us or 225-925-3980 or local veterinarian or LSU AgCenter extension agent.

The New World screwworm (Cochliomyia hominivorax) is a parasitic fly whose larvae feed on the living tissue of livestock, pets, wildlife and, in rare cases, humans. It was eradicated from the United States in 1966, was found briefly in the Florida Keys in 2016 and 2017. It was confirmed in Texas on June 4, 2026, marking the first detection in the U.S. in nearly a decade.

New World screwworm (NWS) infection is a parasitic infestation caused by the larvae (maggots) of Cochliomyia hominivorax..

Affects all warm‑blooded animals including livestock, pets, wildlife and rarely people.
Adult flies lay eggs in open wounds, and the larvae feed on living tissue as they develop. In contrast, maggots from blow flies commonly found in the U.S. feed only on dead or dying tissue, not healthy living tissue.
Although NWS flies can rarely lay eggs on people, animals infected with NWS do not pose a direct human health risk.
Properly inspected and processed meat does not pose a food safety threat