Mexican cattle imports suspended after New World screwworm detected

The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) announced that a New World screwworm (NWS) was detected in Mexico on Friday, causing the agency to pause animal imports from the country.

Mexico’s chief veterinary officer said they discovered the screwworm in a cow at an inspection checkpoint close to the border with Guatemala.

“Given the northward movement of NWS, APHIS has in recent months stepped up its efforts in Central America to partner with impacted countries to push this pest out of newly affected areas,” Dr. Rosemary Sifford said.

“With this latest find in Mexico, we will further intensify this work to protect American agriculture and reestablish the barrier in Central America," she added, according to the release.

NWS are fly larvae that infest living tissue of warm-blooded animals, including humans, causing infection according to the department. The worms often enter animals through open wounds and don't travel more than a couple of miles — unless suitable animals are hard to find in the area, officials explained.

"Screwworm infestations are difficult to detect at first. Check your pets and livestock for draining or enlarging wounds, and signs of discomfort," the release states. "Also look for screwworm larvae or eggs."

"Screwworm eggs are creamy and white and are deposited on near the edges of superficial wounds," it continues. "If you suspect your animal is infected with screwworm, contact your veterinarian."

The agency said it will continue working with Mexico and Central America to respond to the infestation.