Sterile Flies Being Released as Part of San Angelo Screwworm Response

SAN ANGELO, TX — City and county officials held a press conference Tuesday afternoon to outline the local response to a confirmed New World screwworm case in Tom Green County, including a local disaster declaration signed Friday to access state and federal resources. 

The case, involving livestock north of San Angelo between Grape Creek and Carlsbad, prompted the declaration by San Angelo Mayor Tom Thompson and Tom Green County Judge Lane Carter. Officials said the step opens pathways for assistance without guaranteeing direct reimbursements. 

An infested zone — roughly a 12-mile radius around confirmed cases — has been established on the northern side of San Angelo and in Tom Green County. Livestock moving out of the zone requires inspection by Texas Animal Health Commission personnel, official identification, and reporting of destination. Systemic treatment may be needed depending on the animals’ final destination; direct-to-slaughter rules differ. Inspections are free. 

Sterile fly releases have begun in the area following confirmation of the case, and fly traps have been placed. Officials confirmed government vehicles, both marked and unmarked, are conducting the drops. No wild New World screwworm flies have been captured in traps to date, according to state and federal partners. 

A dedicated website at www.sanangelo.gov/screwworm provides daily updates from the Texas Animal Health Commission, USDA and Texas A&M AgriLife Extension. It includes information on animal movement, restrictions, prevention steps and a hotline for suspected cases. Reporting suspected infestations connects owners with free inspectors and resources. 

The Texas A&M Agrilife Extension also has a dedicated page to the screwworm here.

New World screwworm is a parasitic fly whose larvae feed on the living flesh of warm-blooded animals, including livestock, horses, pets and wildlife. Officials stressed it is not a contagious disease and poses minimal risk to humans. They urged daily checks of animals for wounds and prompt treatment.

“It’s not a reason necessarily to panic. We have tools in the toolbox, we have strategies to deal with this situation,” said Jake Thorne, Texas A&M AgriLife Extension small ruminant specialist. Charlie Christensen of Producers Livestock Auction, representing the region’s major sheep and goat market, said commerce continues and the market remains open. He noted potential economic pressure on sheep and goat movement out of state due to other states’ requirements but said the situation is manageable with proper protocols. 

Horses leaving the infested zone also require inspection. There are currently no specific movement restrictions for dogs and other pets, though owners should consult their veterinarians. Checkpoints are in place on the perimeter of the infested zone; vehicles passing through without stopping in the zone face no additional requirements. 

An educational program on the New World screwworm is scheduled for 5:30 p.m. to 8 p.m. Monday, June 29, at the First Financial Pavilion, 4400 Grape Creek Road, in San Angelo. The free event, hosted by Texas A&M AgriLife Extension in partnership with Central Texas Farm Credit and Palmer Feed, features entomologist Dr. Sonja Swiger, a Texas Animal Health Commission representative, veterinarian Dr. Tyler Davidson and a panel including Texas Parks and Wildlife. Two continuing education units are offered. RSVP by June 26 by calling (325) 659-6522 or scanning the QR code on promotional materials. 

Officials described the situation as fluid and in its early stages. They encouraged residents and producers to monitor the website, contact the Texas Animal Health Commission incident command at 737-292-9983 for inspections, and work with local veterinarians and county extension agents. 

“Help is on the way. Help is here,” said Jose Rivera, San Angelo and Tom Green County Emergency Management Coordinator. 

The response involves close coordination among the city, county, Texas Animal Health Commission and USDA. Officials said livestock movement and business operations will continue with appropriate safeguards in place.