Mexico and US inaugurate sterile fly facility to combat screwworm outbreak

Mexico and the United States inaugurated a US$50 million sterile fly production plant in Chiapas, Mexico, on Saturday to suppress the New World screwworm outbreak that has infected over 30,000 animals in Mexico and prompted a US ban on live cattle imports since May 2025 Source: Mexico News Daily.

Facility and Strategy

The plant, located in Metapa de Domínguez near the Guatemala border, is expected to eventually produce up to 100 million sterile flies per week. The sterile insect technique aims to reduce the screwworm population by releasing sterilized males that mate with wild females, leading to no offspring. Mexican Agriculture Minister Columba Jazmín López Gutiérrez called it "a major step in protecting the health of all warm-blooded animals" Source: Mexico News Daily. US Secretary of Agriculture Brooke Rollins noted that the two countries have beaten the pest before and will do so again Source: Mexico News Daily. The US also plans its own sterile fly facility in Texas Source: Mexico News Daily.

Outbreak and Trade Impact

Since the first confirmed case in Mexico in November 2024, the screwworm has spread northward, with 27 animal cases confirmed in the United States, including in Texas Source: CNN. The US border closure to live Mexican cattle since May 2025 has disrupted a trade that previously supplied over 1 million animals annually to US feedlots, forcing Mexico to export meat instead of live cattle Source: Mexico News Daily. Mexico has inspected over 5.3 million head of cattle but the pest continues to spread Source: Mexico News Daily.