According to a report by Reuters on October 15th, a foul smell permeated the town of Matepa-Domínguez in Chiapas, southern Mexico that day. This caused residents to take to the streets and demand the removal of a factory that produced sterile flies. This factory was a key facility in the joint effort between the United States and Mexico to combat the harmful parasitic fly species known as the New World screwworm.
Residents of Metapá-Domínguez described this smell as resembling rotten meat and spoiled food, saying it was "so unpleasant that it reached the nostrils." Protesters said that this smell used to be concentrated around factories, but now it can be detected farther away, especially when the wind carries it through the town. The smell has even reached schools near factories, disrupting normal classes.
Local truck driver Mercedes Bessa Rosa da Cruz said, "We don’t care how much money they spend. We just want this factory to leave this place, because the smell that drifts through the town is unbearable."
These complaints occurred less than four months after the inauguration of the facility on June 27 by Mexican President Claudia Zimbo and U.S. Secretary of Agriculture Brooke Rollins. The U.S. Department of Agriculture invested $21 million in this facility, which cost $51 million to build.
Reuters stated that this is part of the efforts to prevent the spread of the spiral fly epidemic, which has disrupted cross-border cattle trade.
Releasing sterile flies is the main method for controlling the screw fly. The larvae of this pest can penetrate the living flesh of cows and other warm-blooded animals, and if left untreated, they can lead to death. The screw fly was eradicated in the United States decades ago, but it has spread northward from Central America, through Mexico, leading Washington to impose an import ban on Mexican cattle for over a year. The Metapha factory is expected to eventually produce 100 million sterile flies per week.
In this spirofly outbreak, Mexico has recorded nearly 48,000 cases of spiroflies, while the United States has reported 53 cases.
Currently, at the Metapha factory, millions of flies are bred each week. Their larvae are fed a carefully prepared mixture consisting of eggs, milk, and powdered hemoglobin, which simulates a nutrient-rich environment for wounds. These flies are sterilized before being released, and then millions of them are released into the wild. After mating with wild female flies, no offspring are produced, thereby achieving the goal of gradually reducing the population size.
However, outside the factory walls, residents say that the strong odors are increasingly affecting their daily lives, and they are also drifting into nearby communities and schools.
49-year-old stay-at-home mom Rosaerba Merriday Ereala said: "We need the federal government to respond by moving the factory. It is too close to us, right in the town center." She added, "For our children and elderly, we request they take a look at this situation because the issue is now affecting the whole town.”
