Screwworm Eradication Program

The United States successfully eradicated New World screwworm in 1966 using the Sterile Insect Technique (SIT), one of the most successful pest control programs in history. The USDA is expanding sterile fly infrastructure to respond to the current screwworm presence in the U.S.

How Sterile Insect Release Works

• Large numbers of male flies are sterilized.
• Sterile males are released by aircraft into affected regions.
• Wild females mate with sterile males, producing no offspring.
• The population declines over time and can be eliminated.

The 1966 program removed screwworm from the U.S. and continues to serve as a global model for eradication.

Current Efforts

• Large-scale sterile fly production is taking place in Panama.
• Production and distribution in Mexico and the United States have expanded.
• Ongoing efforts are coordinated internationally to prevent reinfestation.
• New U.S. facilities are planned that will produce up to 300 million sterile flies per week.

Sterile fly release remains the primary and most effective method for controlling and eradicating screwworm.

• More about eradication efforts USDA