Texas Agriculture Commissioner Sid Miller confirmed on Wednesday a case of the New World screwworm has been detected in Tamaulipas, Mexico, according to a news release.

The screwworm was identified on Dec. 27, 2025, in a 6-day-old calf, according to the news release. Miller received confirmation from Mexico’s National Service of Agro-Alimentary Health, Safety, and Quality.

This marks the first reported case in Tamaulipas, approximately 197 miles from the U.S.-Mexico border, and the northernmost active detection to date.

Miller released the following statement:

"The continued detections of New World screwworm near the Texas border are grim reminders of the serious threat this pest poses to our state. Thanks to the efforts of USDA Secretary Brooke Rollins and APHIS working in coordination with Mexico, its northward spread has been halted, and this recent case promises to be a one-off, for now. But to fully eradicate this threat, the bottom line remains unchanged: we need sterile flies. I said as much a year ago when I criticized the Biden Administration’s failed efforts to corral this pest—dollars don’t kill screwworms, sterile flies do.

Under President Trump’s leadership, Secretary Rollins and the USDA have now committed to a historic, targeted response that will deliver real results. Earlier this year, I was proud to stand alongside Secretary Rollins in Edinburg, Texas, as she unveiled her comprehensive five-point plan, and again at the Texas Capitol as that plan was expanded. I will continue to support and advocate for federal efforts to expand sterile insect fly production and infrastructure, because this proven strategy is key to the long-term eradication of New World screwworm."