A new United States screwworm case brings the total in the country to sixteen. Mexico has nearly 30,000 reported cases since November 2024, with 1,800 still active, meaning this could quickly escalate if failures to eliminate the parasite persist.

According to a United States Department of Agriculture (USDA) screwworm dashboard, the U.S. cases thus far involve cattle, sheep, goats, and one dog. The case confirmed on Monday was in Terrell County, Texas.

On Sunday, another case was confirmed in Edwards County, Texas.

“The case was identified in a castration site wound. NWS only infests open wounds — it does not affect healthy skin. This detection is approximately 180 miles west of the initial Texas detection and 74 miles west of the nearest previously confirmed case,” the post said in part.

Is The Screwworm A Problem For The Meat Supply?

The confirmation comes amid growing concern among ranchers and animal health experts following reports of screwworm detections in parts of North and Central America. Response teams have intensified inspections, public outreach efforts, and containment activities, including the use of sterile insect techniques that have historically proved effective in suppressing screwworm populations. Officials are also urging livestock owners to promptly report suspicious wounds and infestations. –Yahoo News

While the New World screwworm poses a significant threat to livestock, wildlife, pets, and, in rare cases, humans, it is still not a major risk to the US. Federal and state authorities are working to identify potential additional cases and monitor animal movements to reduce the risk of further spread of the parasite.

The concerning part is that the outbreak is centered in Mexico; however, the screwworm seems to be working its way north through the US.

Federal and state government officials spent decades eradicating the pest through a program that released sterile male flies to prevent reproduction, NBC News reported.  This procedure helped the U.S. reach zero cases in 1982. Unfortunately, that appeared to be only a temporary solution.

As Screwworm Spreads, USDA Partners With DHS Attempting To Control It