On Dec. 27, Mexico’s National Service of Agro-Alimentary Health, Safety, and Quality (SENASICA) reported a new case of New World screwworm (NWS) in a 6-day-old calf with an umbilical lesion in Llera, located in the state of Tamaulipas, approximately 197 miles from the U.S.-Mexico border.
According to the Texas Animal Health Commission, there have been no other detections in Tamaulipas or any evidence of established fly populations in the area.
To support a swift response if NWS reaches Texas, producers located on the southern border and travelers from NWS-affected areas should closely monitor animals for signs and promptly report suspected cases of NWS.
Read more about how to identify NWS:
The Smell You’ll Never Forget: A Calf Infested with New World Screwworm
Protect Your Livestock: Signs of New World Screwworm
A suspected NWS case requires immediate action, but it all starts with one thing: your call. If you suspect an infestation, report it right away.
The Texas Animal Health Commission recently posted this video explaining the process for producers to take if they suspect a NWS case:
What Are Some Key Concerns if NWS Crosses the Border?
Texas beef producer Donnell Brown says NWS poses a real threat to rural America.
“Fortunately, we made it to winter without a major screwworm infestation in the United States,” he says. However, as temperatures rise this spring and fly season begins again, I am deeply concerned that we could see an outbreak with devastating consequences for livestock and wildlife.”
Read more about NWS and winter:
Winter: The Secret to Slowing the Spread of Screwworm
Brown recalls the previous NWS outbreak in Texas.
“Compared to the last screwworm epidemic I experienced as a child, we now have far more effective parasiticides with extended protection for livestock,” he says. “Unfortunately, we still lack practical ways to treat or protect wildlife. After the screwworms were eradicated in the 1970s, it was 15 years before I remember seeing deer on our ranch. Today, deer are abundant and hunting has become a major economic driver for ranchers and rural communities.”
Read more about NWS treatment and prevention options:
FDA Approves Exzolt Cattle-CA1 for Prevention and Treatment of New World Screwworm
FDA Approves Dectomax-CA1 for Prevention and Treatment of New World Screwworm
New Technology to Combat New World Screwworm
Browns says if NWS cause significant wildlife losses, the ripple effects would be severe.
“Fewer hunters would travel from cities to rural areas, reducing spending on food, fuel, feed, lodging and other local necessities. This would harm rural economies already under pressure,” he explains. “The risk is especially high because fawns and many other wild mammals are born during fly season. Their wet navels become prime targets for screwworm infestation, making the potential impact on wildlife populations both immediate and profound.”
Read more about NWS and wildlife:
The Importance of Wildlife Monitoring for New World Screwworm
Sterile Flies Remain Key to Eradicating New World Screwworm
“The continued detections of New World screwworm near the Texas border are grim reminders of the serious threat this pest poses to our state,” says Texas Agriculture Commissioner Sid Miller. “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,” Miller says. “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.”
Current information related to NWS is available on the USDA-APHIS website, including a current situation map and table showing cases within 400 miles of the U.S.
Your Next Reads:
The Battle at the Border
Preparing for the Battle Continues: USDA Shares Screwworm Update and Releases NWS Playbook
