Mexican President Claudia Sheinbaum Slams Trump Admin's Beef Import Ban

Mexican President Claudia Sheinbaum on Monday criticized U.S. President Donald Trump's administration over its temporarily suspension of Mexican beef cattle imports, calling the 15-day ban "unfair" while expressing concerns over its potential economic fallout.

United States Department of Agriculture (USDA) Secretary Brooke Rollins announced the ban on Sunday, citing an advancement of the New World screwworm (NWS) in shipments from Mexico, adding strain to an already tense trade relationship between the neighboring countries.

Newsweek reached out to the Mexican Foreign Ministry and USDA via email on Monday for comment.

What Are New World Screwworms?

New World screwworms are parasitic larvae of the Cochliomyia hominivorax fly that can invade the tissues of any warm-blooded animal, including humans, according to the Associated Press (AP). The parasite enters through open wounds or natural orifices, where larvae then burrow or "screw" into flesh, causing serious and potentially life-threatening damage and lesions.

According to the Texas Parks and Wildlife Department, NWS was eradicated from the United States in 1966, though it remains prevalent in parts of Central and South America. A return of the parasites to the U.S. would trigger major health concerns, along with fears over its economic impact on American agriculture.

The Centers for Disease Control and Prevention also notes, "If you have an NWS infestation, you may see maggots (larvae) around or in an open wound. They could also be in your nose, eyes, or mouth."

What To Know

Sheinbaum described the decision as "unfair" during her Monday morning news conference, emphasizing that "the Mexican government has been working on all fronts from the very first moment we were alerted to the screwworm."

The Mexican president expressed hope that the suspension would not result in another economic blow to her country, as she has spent months scrambling to offset tariff threats from Trump.

The U.S. previously restricted Mexican cattle shipments in late November 2024 after initially detecting the pest but lifted that ban in February after protocols were established to evaluate animals before entry. But the USDA on Sunday said that there has been an "unacceptable northward advancement" of the screwworm, prompting the new suspension.

Mexico's Health Ministry issued an epidemiological warning this month following confirmation of the country's first human case of screwworm myiasis on April 17, in a 77-year-old woman in the southern state of Chiapas.

The parasite has been detected approximately 700 miles from the U.S. border in the Mexican states of Oaxaca and Veracruz.

The USDA has emphasized that this action is not politically motivated but necessary for food security and animal safety. This comes at a time when the southern border has received heightened attention as Trump was elected last year following a campaign focused heavily on illegal immigration. On January 20, following his inauguration, he signed multiple executive orders aimed at curtailing illegal entry and ending the Biden administration's policies.

In southern Texas, residents are being urged to monitor pets, livestock and wildlife for symptoms including irritated behavior; smell of decaying flesh; presence of maggots in wounds; head shaking; and loss of appetite. Each female NWS fly can lay up to 300 eggs at once, making early detection critical.

What People Are Saying

Sheinbaum: "We do not agree with this measure. The Mexican government has been working on all fronts from the very first moment we were alerted to the screwworm."

Rollins said in a statement on Sunday: "The United States has ordered the suspension of livestock imports through ports of entry along our southern border after the continued spread of the New World Screwworm in Mexico. [Mexican Agriculture] Secretary [Julio] Berdegué and I have worked closely on the NWS response; however, it is my duty to take all steps within my control to protect the livestock industry in the United States from this devastating pest."

She added: "The protection of our animals and safety of our nation's food supply is a national security issue of the utmost importance...This is not about politics or punishment of Mexico, rather it is about food and animal safety."

Speaking previously to Newsweek, Phillip E. Kaufman, professor and head of the department of entomology at Texas A&M University, said: "To eliminate the fly, especially under a more widespread infestation, requires several complimentary approaches, including monitoring for infested wounds for larvae, using fly-specific traps, and the mass release of sterile males."

He added: "The sterile male technique is crucial in this process as the female screwworm fly mates only once and by inundating the infested area with sterile males, we in effect make the females lay eggs that do not hatch. As these wild females die out, the population drops, and the fly is ultimately eliminated. This takes time to accomplish but has been proven effective repeatedly."

What Happens Next

The USDA will continue daily collaboration with Mexican authorities and a review of the latest data is scheduled in two weeks. The agency is deploying "Tick Riders" to monitor livestock and wildlife along the southern border for signs of NWS. Officials note that effective eradication requires field surveillance with education and outreach, controlled animal movement and sustained sterile insect dispersal.

The ban will persist on a month-by-month basis until containment efforts show significant progress. Livestock already in holding for entry will be processed normally, including inspection and treatment by Animal and Plant Health Inspection Service port veterinary medical officers.

Reporting from the AP contributed to this article.

Update 5/12/25, 3:16 p.m. ET: This article has been updated with additional information.