The U.S. Department of Agriculture has confirmed two additional cases of New World screwworm, bringing the total number of detections in the United States to four and raising concerns about a broader spread of the parasite.
New Cases in Texas and New Mexico
The fly was detected in a calf in La Salle County, Texas, and a dog in New Mexico, the agency announced in a Monday release. This follows two cases confirmed last week in calves in Zavala County, South Texas, marking the first U.S. detection of the fly in over a decade and the first in cattle in about half a century.
The latest detection in La Salle County is close to Zavala, where the previous two cattle cases were confirmed. However, the confirmation of screwworm in the dog places the pest far outside that region and across state lines. The animal was initially linked to Andrews County, Texas, because it was reported by a veterinarian there, but the dog's home is in Lea County, New Mexico, the USDA clarified later Monday.
Response and Investigation
While the dog case is believed to be isolated, the USDA and state partners are inspecting additional animals in the dog's home area and increasing outreach, as the dog's recent travel and exposure history remain unknown. The agency earlier stated that the dog was believed to have been in Mexico recently.
Agriculture Secretary Brooke Rollins said on CNBC that the U.S. is investing over US$1 billion to push the New World screwworm out of the country.
Impact on Cattle Industry
The spread risks additional cautionary measures to limit cattle movement. Georgia's Agriculture Department restricted the movement of livestock and pets from a dozen Texas counties, while Canada is blocking the transit of livestock that has been in Texas within a three-week window.
This adds further worries for a U.S. beef industry already struggling with supply tightness as the domestic herd has dwindled to a 75-year low. The detection of screwworm is likely to delay efforts to expand the U.S. herd, according to Glynn Tonsor, a professor of agricultural economics at Kansas State University. He noted that increased dryness and now screwworm are creating more uncertainty.
Tighter cattle supplies, even if limited to Texas, would continue to pressure beef processing plants already operating at losses due to the cattle shortage. Companies like Tyson Foods Inc. and JBS NV have resorted to closing plants amid high cattle prices.
Feeder cattle futures in Chicago have risen about two percent since the first Texas case was reported. Tyson shares fell as much as 2.3 percent on Monday, while JBS slumped as much as 6.1 percent to its lowest price since U.S. trading began.
