US tally reaches 71 screwworm cases, 18 still active
Arizona agriculture officials announced the state’s first case of New World screwworm, making Arizona the third U.S. state to report the flesh-eating parasite during the ongoing outbreak.
The Arizona Department of Agriculture said the parasite was found in a heavily maggot-infested wound on a dog’s back in Cochise County. A local veterinarian examined the animal Monday evening, the department said.
Samples from the dog were tested and confirmed Wednesday, the U.S. Department of Agriculture said in a statement. The infected dog was under veterinary care, state agriculture officials said.
The department said it was working with the veterinarian and the dog’s owner to gather information about the infection to guide the epidemiological investigation and local response, including coordination with neighboring states and Mexican partners.
“We have been preparing for this possibility for a long while and are acting swiftly,” Dr. Ryan Wolker, Arizona’s state veterinarian, said in a statement.
According to the USDA, federal and state animal health officials were establishing a 20-kilometer (12.4-mile) infested zone around the site of the detection, releasing sterile flies, increasing live animal surveillance and trapping, and implementing targeted outreach to local producers, veterinarians and communities.
Seventy-one cases of New World screwworm have been detected in the United States — 18 currently active — since the first was reported June 3, according to the USDA’s New World screwworm dashboard. Cases were also detected in New Mexico and Texas.
The detection comes a week after U.S. agriculture officials announced the first known case of the parasite found in U.S. wildlife, discovered by a hunter in a female elk in Texas.
The current outbreak began in Panama and Costa Rica in 2023. Since then, cases in animals and people have been reported across Central America, Mexico and now three southern U.S. states.