Louisiana restricts animal movement after flesh-eating screwworm reaches Texas
The New World screwworm was eradicated in the U.S. decades ago but was recently detected in a calf near the Mexico border
MONROE, La. (KNOE) - Louisiana agriculture officials have issued new restrictions on the movement of animals into the state after a flesh-eating parasite that had been eradicated in the U.S. for decades was detected in Texas.
The Louisiana Department of Agriculture and Forestry said the restrictions are effective immediately and will remain in place until further notice.
The rules were announced after the U.S. Department of Agriculture confirmed New World screwworm in a 3-week-old calf in LaPryor, Texas, about 50 miles from the Mexico border. Federal officials said it was the first confirmed case in Texas since 1966.
New World screwworm is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals. Female flies lay eggs in open wounds or body openings, including the nose, eyes, ears and mouth. The eggs hatch into larvae that can cause painful wounds, serious infections and death if left untreated.
The parasite can infest livestock, wildlife, pets and, in rare cases, people. Federal officials said the parasite does not infest food.
READ MORE: Screwworm fly detected in Texas decades after cattle threat was largely eradicated in US
The screwworm was once a major threat to cattle and other livestock across the southern U.S. before it was eradicated in the 1970s through the release of sterile flies. The method works because female screwworm flies mate once, and eggs do not hatch if the female mates with a sterile male.
U.S. and Texas agriculture officials had been warning for months about the parasite moving north through Mexico. The USDA has said there have been no other detections in the U.S. and that officials do not believe the Texas case will lead to the pest becoming established in the country.
Under Louisiana’s new restrictions, animals traveling from a New World screwworm-infested state may enter Louisiana if they are not coming from or passing through an infested zone and have an Official Certificate of Veterinary Inspection.
That certificate must include the statement, “All animals in shipment do not originate from or transit through an NWS-infested Zone.” The certificate is valid for no more than seven days from the date of inspection.
Animals that originate from or travel through an infested zone may only enter Louisiana if they meet all movement requirements from the state of origin, obtain a permit from LDAF’s Office of Animal Health and Food Safety and have an Official Certificate of Veterinary Inspection.
That certificate must state, “All animals listed were individually inspected and found free of evidence of NWS infestation.”
Owners, veterinarians and transporters are urged to review current movement requirements before shipping animals and to report suspected cases immediately.
Suspected cases can be reported to LDAF at (225) 925-3980 or vetreports@ldaf.state.la.us.
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