
The United States and Mexico, long at odds over tariffs, illegal immigration, and unfulfilled water supply agreements, are now locked in a new dispute over screwworms.
On Monday, U.S. Secretary of Agriculture Brooke Rollins announced via social media the immediate suspension of live cattle, horses, and bison imports from Mexico entering through U.S. southern border ports.
Reportedly, the reason given for the ban is to prevent the spread of New World Screwworm (NWS), a type of parasitic fly species. NWS infection is known to be lethal to livestock, pets, wildlife, and even humans.
Rollins asserted that the northward advancement of NWS is unacceptable and emphasized that the dangerous pest poses a serious threat to the food supply and national security.
In response to this announcement, the Mexican government criticized the U.S decision as unfair.
During a regular press briefing, Mexican President Claudia Sheinbaum stated that the decision by the U.S. government is unfair. She explained that the screwworms have been found in some areas, and the Mexican government is also taking all measures for eradication.
Julio Berdegué, Mexico’s Agriculture Secretary, also wrote on his social media account that the unilateral action by the United States does not help the joint efforts to control the NWS disaster.
However, Berdegué later modified his message, stating that they don’t agree with this measure, but they’re confident they’ll reach an agreement sooner rather than later.
According to the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS), NWS, locally referred to as screwworm, has historically plagued the southern U.S., Mexico, Central America, Caribbean islands, and parts of South America, with devastating effects on animals.
When NWS flies attach to wounds on livestock, pets, wildlife, birds, or humans and lay their eggs, the hatched larvae burrow into flesh, causing fatal damage.
To combat NWS, the U.S. government has cooperated with Mexico and other countries since the 1950s and 1960s, using the Sterile Insect Technique (SIT) that involves releasing sterilized male parasitic flies. As a result, they officially declared the pest eradicated in the 1980s. However, localized findings occurred in the U.S. mainland, including Florida, in 2016.
Rollins underscored the historical impact, noting that the last time this devastating pest invaded America, it took 30 years for their cattle industry to recover. This cannot happen again.