Screwworm Information
New World screwworm (NWS) is a serious pest of livestock and wildlife.
This invasive pest we previously eradicated from the United States, but has recently been reintroduced (June 2026). Website links below provide information on screwworm, including prevention and treatment for screwworm. Treatment and prevention, as well as reporting requirements, often vary by state - contact animal health officials in your state for state-specific requirements and recommendations.
FEDERAL RESOURCES
STATE RESOURCES
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California Department of Food and Agriculture (CDFA)
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University of California at Riverside
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Florida Department of Agriculture & Consumer Services
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Texas Animal Health Commission
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Texas A&M Agrilife Extension
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New Mexico State University
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University of Tennessee
COMMODITY GROUP RESOURCES
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AVMA
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NCBA
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Swine Health Information Center
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American Sheep Industry Association

Horses
Flies
Photo by CSIRO science image
Photo by Fritz Geller-Grimm
Photo by Katja Schulz
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Photo by Alan R Walker
Photo by Bruce Marlin
Photo by Phillip Kaufman
Photo by USDA
Photo by James Gathany, CDC
Photo by Judy Gallagher
Mites
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