New World screwworm cases escalate Texas response, disaster aid

As the number of confirmed New World screwworm cases in the U.S. grows to four, Texas and the federal government are working to stop the threat before it spreads.

Texas Gov. Greg Abbott escalated the state response Friday by issuing county-specific disaster declarations for Zavala and Uvalde counties as he warned residents to brace for a “challenging summer" during a June5news conference.

Agencies like the U.S. Department of Agriculture and the Texas Animal Health Commission have also moved into a coordinated containment effort to avoid potentially billions in losses for ranchers and the broader food supply.

Here is what we know about the two confirmed cases, the quarantine zone and how state and federal officials are responding.

Where the 4 screwworm cases were confirmed

The U.S. Department of Agriculture confirmed the following in three in South Texas, two in Zavala County and another in La Salle County. The fourth case was reported in Gillespie County — near Fredericksburg, Texas.

A case was originally in Andrews County; however, USDA later reclassified the case to New Mexico — marking the first case in the state.

What Gov. Abbott's disaster declaration does

Texas Gov. Greg Abbott further escalated the state's response on Friday, June 5, by issuing a disaster declaration for Zavala and Uvalde counties.

According to the order, the governor has reallocated all available state resources that "are reasonably necessary to cope with this disaster, and temporarily reassign any such resources that could be allocated to address the spread of NWS to the Texas New World Screwworm Response Team," prioritizing the resources to Zavala and Uvalde counties first.

Abbott also directed the Texas Division of Emergency Management to activate the Texas State Emergency Operations Center at a Level II — escalated response — on Monday, June 8.

“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,” Abbott said in a statement.

Abbott had already issued a statewide disaster proclamation in response to the NWS threat on Jan. 29 and has renewed it monthly since then.

What the expanded quarantine zone restricts

The Texas Animal Health Commission (TAHC) updated its emergency order on Friday, June 5, expanding the quarantine zones covering parts of Zavala and Uvalde counties southwest of San Antonio. The original order, signed by Executive Director Lewis Dinges on June 3, imposed restrictions on the movement of animals out of the area after a Zavala County calf tested positive for NWS.

Under the order, the quarantined area is subject to the following:

• Warm-blooded animals located within the quarantined area may not be moved outside of the zone without prior authorization from TAHC.
• Any person in possession or control of such animals must obtain permission and comply with all conditions set by TAHC before transporting the animals beyond the quarantine boundaries.
• To move warm-blooded animals outside of a quarantined area, the animal must be inspected and treated as required by the TAHC and issued a permit or certificate for movement by a TAHC representative.
• Hides, carcasses, and parts of any animal that can serve as a host for NWS must be inspected and treated as deemed necessary by a TAHC representative prior to removal from the quarantine area.
• Unauthorized movement is prohibited and subject to administrative penalties or criminal prosecution.

The order went into effect immediately on June 3 and is set to remain in effect until the quarantine is lifted by TAHC.

USDA continues sterile New World screwworm fly releases

According to the USDA, the department is continuing its sterile fly release operations over the infested areas and along the U.S.-Mexico border.

Starting on Tuesday, June 9, aerial dispersal flights originating from the sterile fly dispersal facility at Moore Air Base in Edinburg, Texas, will begin.

Due to the nature of the releases, USDA said it is possible that sterile NWS flies could be caught and reported, but it has taken steps to ensure officials can differentiate between sterile and wild NWS flies.

What the New World screwworm is, how it spreads

According to the USDA, the New World screwworm (NWS) is a parasitic fly that impacts livestock, pets, wildlife, and, less commonly, people and birds. The fly's larvae feed on the living tissue of warm-blooded animals.

USDA reports that the current risk to animals and people in the United States remains very low and that NWS is not contagious.

Rather, screwworm infestations begin when a female fly lays eggs on a wound or body opening. The eggs hatch intolarvae that burrow into the wound and feed on living tissue, then after about 7 days of feeding, larvae drop to theground, burrow into the soil, and pupate.

The adult screwworm fly emerges from the soil after 7 to 54 days.

Who is leading the Texas state response to the screwworm

According to the TAHC, the commission was established in 1893 and is charged with protecting the state's domestic animals "from all contagious or infectious diseases of a malignant character."

The 13-governor-appointed commission has legislative authority to make and enforce regulations to prevent, control, and eradicate specific infectious animal diseases that endanger livestock, representing the general public and various livestock industries and professions.

Under Title 4 of the Texas Administrative Code, the commission has the authority to quarantine any area, county, or part of a county within the state that has been determined to be infested with NWS, as laid out in Section 37.1.

Mateo Rosiles is the Texas Connect reporter for USA TODAY and its regional papers in Texas. Got a news tip for him? Email him at [email protected].