As the New World screwworm (NWS) parasite inches closer to the U.S.-Mexico border, federal officials have conditionally approved the first medication designed to prevent and treat infections in cattle.
The U.S. Food and Drug Administration (FDA) announced Tuesday that it has granted conditional approval to DECTOMAX®-CA1, a treatment developed by Zoetis. According to the company, the drug both treats NWS infections and prevents reinfestation for up to 21 days in cattle.
FDA Commissioner Marty Makary said the decision reflects the urgency of the situation facing U.S. livestock producers.
“We understand the urgency with which America’s farmers and ranchers are asking for tools to fight New World screwworm,” Makary said in a statement. “Today’s conditional approval – the first in the U.S. for NWS — shows our dedication to rapidly advancing important animal medicines when they are needed most. We continue to work tirelessly to complete review of other NWS products to protect multiple animal species in the U.S.”
U.S. Department of Agriculture (USDA) Secretary Brooke Rollins called the approval a “victory” for cattle producers, though she hinted that additional updates will be announced soon.
The NWS, a parasitic fly, causes severe damage to livestock, wildlife, and even humans. Female flies lay eggs on open wounds; once hatched, larvae burrow into living flesh, feeding on tissue and often causing infections that can lead to death if untreated. Cattle, pigs, and horses are particularly vulnerable.
The approval comes amid rising concerns. On September 21, the USDA confirmed that the NWS was detected less than 70 miles from the U.S. border — the closest detection on record. Previously, the nearest known case was more than 350 miles south.
Federal and state officials have been preparing for the threat for months. In June, Rollins unveiled a five-part plan to combat the parasite. In August, she joined Texas Gov. Greg Abbott to announce an $850 million investment in preventive infrastructure, including a facility to mass-produce and release sterile flies to reduce NWS reproduction and the development of new technologies to counter the pest.
Texas Agriculture Commissioner Sid Miller, speaking recently to The Texas, said he has been in discussions with federal officials about adding “fly bait” strategies to the response. But he noted USDA concerns that such methods could harm the sterile flies being released and potentially damage the environment.
“This isn’t just about cattle — Texas wildlife is also at risk,” Miller said.
While the issue did not appear on this summer’s special legislative sessions, lawmakers are beginning to take notice. The Texas House Agriculture and Livestock Committee is scheduled to hold an interim hearing next week to hear invited testimony on possible legislative responses.
