Texas reports four New World screwworm cases; New Mexico reports its first
As announced earlier today, there are now four confirmed cases of New World screwworm in Texas, with officials keying in on multiple counties along and near the state’s border with Mexico – Gillespie, La Salle, Uvalde, Webb, and Zavala.
Measures being taken include surveillance, movement restrictions, and 12-mile quarantine areas around the case sites, with buffer zones also established.
Three of the Texas cases involve newborn calves and umbilical lesions, with the fourth that of a goat. Lea County, New Mexico, has since reported its first case, a dog that was initially seen by a veterinarian in Andrews County, Texas.
The New World screwworm is a parasitic fly whose females lay eggs in open wounds, with the resulting larvae consuming tissue deep into the host animal. After feeding for about seven days, they drop out of the wound onto the ground, where they burrow in and enter their pupal stage. They then emerge as adult flies anywhere from one to eight weeks later, depending on temperature and humidity conditions.
Culling of cattle herds isn’t done nor necessary, according to the USDA. Infested animals are quarantined during treatment, with the entire herd placed under a hold order until cleared for any movement. Euthanasia of infested animals is only done for humane reasons or if treatment isn’t possible, according to the USDA.
In a recent media release, Gov. Greg Abbott said he’s directed the Texas Division of Emergency Management to activate the Texas State Emergency Operations Center to Level II (escalated response) to support the response.
“I have activated the full use of all state resources to respond to the New World Screwworm threat,” Abbott said. “The protection of our ranchers, livestock producers, deer breeders, and the Texas economy from this pest is a top priority. We have eradicated this pest before, and we will do it again in close cooperation with our federal partners. Texans should stay alert, check animals daily for wounds, and report any suspected cases immediately.”
The following agencies are all involved and are reporting to the emergency operations center:
• Texas Animal Health Commission
• Texas Parks and Wildlife Department
• Texas A&M AgriLife Extension Service
• Texas A&M Veterinary Medical Diagnostic Laboratory
• Texas Department of Agriculture
• Texas Department of State Health Services
The USDA reports that its efforts to address the New World screwworm issue include the release of millions of sterile screwworms via aerial and ground chamber means each week as well as increased trapping measures. Media reports also indicate the USDA has allocated funding for a new $750 million facility in Texas that will be capable of producing hundreds of millions of sterile screwworms upon its anticipated 2027 completion.
A June 8 Forbes article reports the U.S. cattle population is at its lowest in 75 years, and that an outbreak would have several impacts, including an increase in calf mortality. The article notes that “[t]he return of screwworm comes after the Musk-led Department of Government Efficiency, launched by the Trump administration, last year cut funding for a project dedicated to monitoring and containing New World screwworm in Central America.”
A USDA report estimates a $1.8 billion loss to the Texas economy if an outbreak on the scale of its 1976 one occurs. Of that, an estimated $732 million would involve producer losses.
Reports of suspected New World Screwworm cases in livestock should be made to the Texas Animal Health Commission at 800-550-8242, with suspected wildlife cases reported to the Texas Parks and Wildlife Department at 512-389-4505.
Access the latest updates and resources online through the TAHC (tahc.texas.gov), TPWD (tpwd.texas.gov), and U.S. Department of Agriculture (screwworm.gov) websites.
While rare, human infestation can occur. For more information, visit the U.S. Centers for Disease Control and Prevention’s webpage on the topic here.
Additional materials:
Written by Jo Ann Livingston/In The Know Ellis.
