USDA reports no additional New World screwworm detections in Texas

In a press conference on June 4, Agriculture Secretary Brooke Rollins confirmed no new detections of New World screwworm (NWS) in the local area of La Pryor, Texas, since the appearance of the pest in a three-week-old calf a day earlier.

“We’ve had a couple [cases] come through as possibilities,” she said. “None of them we think are positive identifications — certainly none that looked like the one we saw yesterday from La Pryor. But we are running that down, and the minute we get any kind of a confirmation, we will be posting that onto our social media channels and issuing a press release.”

In an effort to avoid misinformation, Rollins announced the launch of a new X account dedicated to timely updates on NWS under the handle @Screwworm_RR.

During the call, Lewis R. “Bud” Dinges, executive director of the Texas Animal Health Commission, described improvement in the affected calf, which had larvae in an umbilical lesion.

“Our staff visited the premises with the infested calf yesterday, and the infested calf is doing much better,” he said. “They looked at the cattle on the premises there and didn’t find any other infested animals. From our … investigation, there is no evidence of a recent movement of animals onto or off of that premises.”

The 20-kilometer area around the infested zone will remain under quarantine for 36 hours initially and up to 72 hours if extended. Animals can move out of the zone, Dinges clarified, if they receive a proper inspection and/or treatment.

Rollins remains optimistic that NWS can be dealt with swiftly in the United States on a case-by-case occurrence.

“If we all work together and follow these treatment and movement restriction guidelines, there is no reason to believe that this incursion will result in any sort of establishment of the pest on our side of the border, which is different from when it hit us in the 1950s and the 1960s,” she said.

Rollins pointed out that when NWS first surfaced in Panama and eventually into Mexico, predictive models indicated the fly would enter the United States by last summer or fall.

“What happened was never supposed to happen again, and that was the breaching of the Darién Gap,” she said. “But as [New World screwworm] began to move up a couple of years ago, all the models predicted that no matter what happened or what we did, that the New World screwworm would be on our side of the border last summer and early fall. We obviously didn’t accept that as an absolute, and the team you see on the call today and back at USDA, the team on the ground, and our great partners in industry, have just been so helpful in getting us that extra year to prepare for this moment.”