New World Screwworm (NWS)

​The New World screwworm (Cochliomyia hominivorax) is a parasitic fly that lays its eggs in the open wounds and mucous membranes of warm-blooded animals, including livestock, pets, and in rare cases, humans.  The larvae, or maggots, feed on the living flesh of the host, which can lead to severe damage and potentially death if left untreated.  The U. S. eradicated the screwworm in 1966, but a recent northward progression of cases from Central America has renewed concerns.  A sterile insect technique, which involves releasing sterilized male flies to prevent the reproductive cycle, is a key tool in eradicating the pest.

COMMUNITY

• NWS: What You Need To Know
• NWS and Agriculture Employees
• NWS and Agriculture Producers

HEALTHCARE PROVIDERS

• About New World Screwworm
• Clinical Overview of New World Screwworm
• NWS: What Healthcare Providers Need To Know

LOCAL HEALTH DEPARTMENTS

• NWS Case Report Form
• Interim Considerations for Advanced Readiness and Preparedness for New World Screwworm (NWS) infestations in Humans

TESTING

• Laboratory Identification of Parasites of Public Health Concern

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RESOURCES

• Current Status of NWS (USDA)
• About the Screwworm Fly

• Singular Traveler-Associated NWS Case