Flesh-eating screwworm outbreak escalates in West Texas as confirmed cases reach 31

Federal and state agricultural officials have confirmed that the number of New World screwworm cases in the United States has reached 31, prompting Texas authorities to maintain strict emergency quarantine orders to combat the flesh-eating parasite's ongoing expansion in West Texas.

According to official records, 30 of the confirmed cases are concentrated across Texas, with one domestic animal case previously identified in Lea County, New Mexico.

The recent spike follows a detection confirmed in a bovine in Crockett County. The case marked the second time in less than a week that the aggressive parasite bypassed active containment barriers in the region, forcing Texas Animal Health Commission (TAHC) Executive Director Dr. Lewis R. Dinges to sign an emergency order expanding strict livestock movement restrictions.

Outbreak escalates in West and Central Texas

The Crockett County bovine detection follows a string of rapidly evolving cases in that area, where the parasite was previously found in sheep.

In response to the expanding cattle infections, Dr. Dinges issued a modified executive mandate establishing Infested Zone 07.B. This order replaces previous restrictions and broadens the quarantine boundaries. The expanded containment zone heavily restricts livestock and animal transport across designated portions of five neighboring counties:

• Crockett
• Schleicher
• Sutton
• Terrell
• Val Verde

This escalation comes alongside separate geographic expansions along the South Texas border, where officials previously established Infested Zone 10 covering parts of Jim Hogg, Starr, and Zapata counties after a bovine tested positive in Jim Hogg County.

View the zone map

OFFICIAL NOTICE: There is currently a quarantine in place due to an established New World Screwworm Infested Zone in parts of the following Texas counties: Bandera, Coke, Crockett, Edwards, Gillespie, Jim Hogg, Kerr, Kimble, La Salle, Medina, Pecos, Schleicher, Starr, Sutton, Terrell, Tom Green, Uvalde, Val Verde, Webb, Zapata, and Zavala.

State Operations Escalate to Level II Response

According to the latest State Situation Report from the Texas Division of Emergency Management (TDEM), the Texas State Emergency Operations Center remains activated at Level II (Escalated Response Conditions) to manage the multi-agency response.

State and federal assets are deploying aggressive containment and surveillance tactics across the region:

• Roadside Checkpoints: TAHC has deployed ten compliance and checkpoint strike teams operating roadside checkpoints within the infested and adjacent zones. Inspectors have already examined 10,965 animals and issued 251 certifications for authorized movement out of quarantine zones.
• Sterile Fly Dispersal: The Texas Military Department (TMD) has activated an Aerial Dispersal Team based out of Edinburg to assist the USDA with the mass release of sterile screwworm flies to disrupt the biological reproductive cycle of the parasite.
• Drone and Trap Surveillance: The Texas Parks and Wildlife Department (TPWD) has established 78 specialized traps, 22 Ground Release Chambers, and secured multiple private and state land locations for USDA Drone Surveillance to map the parasite's spread.
• Human Health Status: The Department of State Health Services (DSHS) confirmed that there are currently no confirmed human cases of New World screwworm in Texas.

Agricultural Threat

The New World screwworm (Cochliomyia hominivorax) is considered a severe threat to livestock, exotic livestock, and wildlife. The parasitic fly targets open wounds, even minor abrasions, castration sites, or tick bites, to deposit eggs. The hatched larvae burrow into live tissue, causing a painful condition known as myiasis, which can be fatal if untreated.

While state animal health officials race to contain the New World screwworm, federal officials previously confirmed the first case of the parasite in a domestic pet dog in New Mexico.

Governor Greg Abbott’s statewide disaster proclamation remains actively in effect to facilitate rapid resource deployment through the State Emergency Operations Center. The state has also launched a consolidated information hub for producers and residents at screwworm.texas.gov.

What you can do:

Livestock and pet owners are urged to inspect animals daily. Suspected cases must be reported immediately to the TAHC at 512-719-0700.

TexasPets and AnimalsHealthEconomy