New World Screwworm Fears Grow as Cases Explode in Northern Mexico

New World Screwworm Map of Active Cases- April 22nd

Active cases of New World Screwworm in the two Mexican states that border Texas in the far southern tip of that state are exploding. Over the past week in the state of Tamaulipas, active cases have jumped from 63 to 116. This state borders the Gulf of America to the east and Texas to the north- near Brownsville. Most cases in Tamaulipas are over a 100 miles from the US border.

Much closer are the increasing cases being reported in Neuvo Leon, where the latest case found in a 7 day old calf was just sixty miles from the US Border. Nuevo Leon reported two active cases as of April 15th- the latest reports(as shown in the map above) up through April 22nd have jumped to 8.

Both states are in the polygon that extends just over the border into the United States where the 100 million sterile flies being produced in Panama are being released.

Mexican authorities reported a thirteen percent jump in total active cases over the past week within 400 miles of the US- from 1,295 active cases up through April 15th to now 1,469 cases up through April 22nd. USDA is watching on both sides of the Rio Grande River- over 7,100 traps are monitored by the USDA on both sides of the U.S.-Mexico border.

Florida Demands Screenings and Treatment of Animals From South Texas

These latest reports near the US border have resulted in Florida announcing restrictions on importation from south Texas to Florida of any warm blooded animal coming out of six south Texas counties. Texas Ag Commissioner Sid Miller offered the following statement after the Florida emergency rule was released:

“Florida’s move is understandable. With the growing threat of New World screwworm, and as ground zero of America’s last outbreak a decade ago, they’re acting to protect their state. This isn’t a distant risk, and their heightened biosecurity makes that clear.

“The impacts of New World screwworm are already here. The extended halt on cattle movement from Mexico alone is straining supply chains, cutting into Texas meatpacking capacity, and pushing prices higher for families nationwide. And let’s be clear; this threat isn’t going away anytime soon.

“While USDA works to build a sterile fly facility and coordinates with Mexico, we cannot afford to wait years for a single solution. We need every available suppression tool in play, now. Our livestock, wildlife, pets, and consumers don’t have time to spare.”

“Florida’s emergency rule imposes temporary controls on animals entering the state from designated “high-risk” areas to prevent the spread of New World screwworm. The rule applies to livestock and other animals originating from six South Texas counties: Zapata, Jim Hogg, Starr, Hidalgo, Webb, and Brooks.”

Florida Commissioner of Ag Wilton Simpson announced ““Today we are taking aggressive action to further protect Florida and our agricultural producers from the real threat of the New World Screwworm,. We know how costly and dangerous this pest can be to our agricultural industry if it takes hold, and we will use every tool at our disposal to protect our state. We’re also calling on Florida’s producers, veterinarians, and animal health professionals to remain aware and act quickly if they suspect something unusual.”

The First of Many Stringent Rules Now in Place for Cattle Coming from Areas Considered High Risk for NWS

The emergency rule imposes the following temporary restrictions on the importation of animals originating from high-risk counties:

Import Requirements: Except where more stringent requirements are adopted herein, all animals being imported into Florida from a high-risk county must meet the movement requirements in Chapter 5C-3, F.A.C.

All warm-blooded animals originating from a high-risk county being imported into Florida must be accompanied by an Official Certificate of Veterinary Inspection (OCVI) documenting that all animals listed on the OCVI have been inspected and found free of contagious and infectious disease and pests, including NWS. No alternative movement documents will be accepted in lieu of an OCVI.
- The OCVI must include the statement, “All animals listed on the OCVI have been inspected and are free from screwworm larvae infestation.”
- The OCVI is valid for no more than 7 days from the date of veterinary inspection.
All warm-blooded animals that have wounds that are not infested with NWS larvae can be imported into Florida provided that the following requirements are met:
- Any animal with a wound must be treated using an effective treatment. The effective treatment must be administered by or directly overseen by an authorized representative or licensed veterinarian. The effective treatment for NWS must be administered in accordance with the following:
  - Oral or injected treatments must be administered no less than 12 hours and no more than 14 days prior to entry into Florida.
  - Systemic, topical treatments must be administered no less than 72 hours and no more than 14 days prior to entry into Florida.
- In addition to receiving a systemic effective treatment, all animals with non-infested wounds must have the wounds topically treated with a product effective against NWS. The wound location and treatment must be documented on the OCVI