As human cases emerge and trade threats loom, officials scramble to defend public health and economic survival.
Facing increasing pressure from the United States over the spread of the screwworm (Cochliomyia hominivorax), Mexico’s Secretary of Agriculture and Rural Development, Julio Berdegué Sacristán, emphasized that the country is taking the issue seriously but with a “cool head”—a posture echoed by President Claudia Sheinbaum.
This week, U.S. Secretary of Agriculture Brooke Rollins warned that if Mexico does not immediately remove barriers to U.S. eradication efforts, including restrictions on USDA aircraft and customs duties on eradication equipment, the United States would move to restrict imports of Mexican livestock by the end of the month. Rollins cited the escalation of the screwworm outbreak as a direct threat to American agriculture.
In response, Berdegué stated via his X account (formerly Twitter) that Mexico is committed to collaboration and cooperation, but will not act under subordination. He expressed confidence that “good agreements” could still be reached to maintain the important agricultural trade relationship between the two countries.
The screwworm crisis is not only an economic threat but also a public health concern. Recently, Mexico’s Ministry of Health confirmed the first human case of screwworm infestation (myiasis) in Chiapas. A 77-year-old woman contracted the parasite but is now stable and receiving medical care.
The screwworm larva targets open wounds in animals and humans, feeding on living tissue. Infected wounds often exhibit severe swelling, intense pain, and tissue decomposition, accompanied by a foul odor. If untreated, infestations can lead to serious health complications.
Adult screwworm flies are medium-sized, metallic greenish-blue insects that lay eggs in wounds. The larvae hatch within hours, making rapid intervention critical.
Senator Marko Cortés Mendoza (PAN) criticized the federal government’s handling of the situation, blaming the “republican austerity” policy for dismantling critical programs like the National Service of Agrifood Health, Safety, and Quality (Senasica). According to Cortés, reduced funding for pest prevention efforts has left Mexico vulnerable to outbreaks like the current screwworm crisis.
He warned that without immediate reallocation of resources to Senasica and a reinvigorated eradication strategy, Mexico could face devastating trade restrictions, including renewed bans on key exports like avocados and livestock.
“The real problem is that this government despises science and prevention,” Cortés said. “Public resources are not being invested where they should be, which is why pests once under control are now resurfacing.”
As the threat spreads, officials are urging both farmers and the general public to adopt strict prevention measures:
- Care for wounds: Keep cuts on both humans and animals clean, covered, and disinfected.
- Control flies: Maintain home hygiene, install screens on doors and windows, and use traps or insecticides to limit fly populations.
- Waste management: Seal and remove trash frequently to avoid attracting flies.
- Livestock care: Regularly inspect animals for wounds and apply veterinary-approved repellents.
Authorities stress that early detection is critical. In the presence of symptoms like unusual swelling, foul odors from wounds, or visible larval movement, immediate veterinary or medical intervention is necessary.
Despite rising tensions, Berdegué remains optimistic that Mexico and the U.S. can navigate the crisis through dialogue. However, with livestock exports—and now human health—on the line, experts warn that swift and scientifically grounded actions are more necessary than ever.
