Screwworm

Sept. 3 (UPI) — The U.S. Food and Drug Administration on Thursday issued an Emergency Use Authorization for two drugs to prevent and treat New World screwworm, or NWS, in dogs and cats.

According to the agency, Capstar tablets and their generic version, nitenpyram, are approved for dogs, puppies, cats and kittens that are at least 4 weeks old and weigh at least 2 pounds.

Nitenpyram tablets were approved for treatment in June.

“Although the FDA has authorized or conditionally approved multiple products for the treatment of New World screwworm in dogs and cats, none were for prevention – until today,” Timothy Schell, director of the FDA’s Center for Veterinary Medicine, said. “The FDA is addressing a previously unmet need and giving pet owners and veterinarians important tools to protect dogs and cats from NWS infestations.”

The U.S. Department of Agriculture has confirmed 48 domestic cases of NWS in animals as of Thursday.

The FDA said most dogs and cats in the United States are at low risk of exposure to NWS because confirmed cases “are in a limited geographic region.” It said that dogs and cats that live, travel to, or return from areas where NWS have been identified, should be watched closely for signs of infestations.

Signs of infestations include visible maggots, foul odors in sounds or body openings. Veterinary care should be sought immediately for infested dogs and cats, the FDA said.

Capster is produced by Indianapolis-based Elanco Animal Health, while nitenpyram is made by Dublin-headquartered Felix Pharmaceuticals.

Aug. 27 (UPI) — The Food and Drug Administration on Thursday issued an emergency approval for the use of the drug ivermectin against New World screwworm infestations in cattle, adding to the arsenal of weapons available against the flesh-eating insect.

The FDA approved an Emergency Use Authorization, or EUA, for Bimectin, the generic version of ivermectin, for injections in cattle when administered within 24 hours of birth, at the time of castration, or at the appearance of a wounds, the agency announced.

Bimectin injection remains unauthorized for use in lactating dairy cows or in calves that will be processed for veal.

Thursday’s move is the 14th EUA issued by the FDA against New World screwworm as the Trump administration attempts to deal with the still-growing infestation in Texas.

The Department of Agriculture has confirmed 47 domestic cases of New World screwworm, or NWS, in animals as of Thursday.

NWS is widely feared as a serious health and economic threat that could cost billions of dollars in losses to cattle, bison and horses. The pest was eradicated from the United States in 1966 and eliminated as far south as Panama by 2000, but reemerged in 2022 and has continued moving north through Central America and Mexico.

The U.S.-Mexico border was closed last year to protect U.S. animals from the threat. The ban was subsequently lifted on July 26.

Texas Agriculture Commissioner Sid Miller last month urged the FDA to authorize ivermectin in feed as an additional tool to combat the growing NWS threat.

Injectable ivermectin is not enough to keep pace with the outbreak and protect livestock from further infestations, he asserted.

“Texas ranchers are fighting for their livelihoods and the security of the American food supply. They don’t have time to wait,” Miller said. “We’ve already seen this parasite spread across multiple Texas counties in just a few weeks. Every day we delay is another day the New World screwworm gains ground. We need every effective weapon available, and we need it now.”

The Texas Grain and Feed Association “has committed to rapidly manufacture and distribute medicated feed upon approval, ensuring producers can begin using it without delay,” he noted.