US, Mexico step up joint efforts to contain flesh-eating parasite outbreak

YUMA, AZ (AZFamily) — Mexico and the U.S. have reached an agreement to step up efforts to contain a growing outbreak of the flesh-eating screwworm parasite in southern Mexico.

USDA Secretary Brooke Rollins had threatened to close the border to livestock and animal commodity imports from Mexico if swift action wasn’t taken to control the outbreak.

Mexico is one of the largest beef exporters to the United States, and halting its livestock and animal commodity exports would have major impacts on the U.S. agricultural industry and supply chains.

More than a million head of cattle are imported to the U.S. from Mexico every year. As U.S. cattle herds have declined, reliance on imports has grown, which is why experts say adding barriers to the beef trade could hurt the ranching industry.

“The Mexico situation is basically exacerbating the problem if we don’t have feeder calves coming in,” said Russell Tronstad, Professor at the University of Arizona for agricultural resource economics.

Secretary Rollins sent a letter to Mexican officials requesting permission to begin preventive measures, such as aerial releases of sterile flies, to stop the screwworm parasite from spreading north toward the U.S. border.

The parasite targets livestock, wildlife, and, in rare cases, humans by burrowing into the skin, causing severe infections that can be fatal if left untreated.

“It is something that will attack people as well so it’s not something we want that’s for sure,” said Tronstad.

He said shutting down the cattle trade between the countries would have been the wrong approach.

“One thing about the tariffs is you can always pay those, but something like this that stops all trade basically there’s no way around it and the impact can be more harmful than a tariff,” he said.

Reuters reported on Monday that Mexico and the U.S. had reached an agreement to combat the screwworm outbreak, just two days before the deadline set by Secretary Rollins for Mexico to take action.

The Arizona Department of Agriculture is closely monitoring the outbreak. In a statement, they said that over 750 screwworm cases had been detected in Mexico and that their state veterinarian was currently working with Customs and Border Protection Inspectors.

Due to the loss of several key USDA Veterinary resources stationed at the southern border and the impending threat of NWS, our State Veterinarian is currently training Customs and Border Protection Inspectors to perform some of the intricate and vital livestock inspections on imports entering into the U.S. New World Screwworm is a foreign animal disease that poses a threat to agricultural commerce, trade, overall animal health, and the nation’s food supply. This pest was originally eradicated from the United States in 1966, and the population mitigation efforts were successful through use of a sterile fly barrier zone in Panama. Unfortunately over the past several months, NWS has been detected north of Panama, and most recently in Mexico. As of last week, there were over 750 detections in Mexico, up from 330 cases as of March 30. While this pest is difficult to detect, the AZDA is working hard to ensure a proactive response and a decreased risk of NWS resurgence in the U.S.

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