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
Eye Gnat
Flies in the genus Liohippelates, formerly Hippelates, are very small and are commonly referred to as “eye gnats” in their range in North and South America due to their propensity for hovering around eyes and other areas with secretions such as the nose or open wounds. Large groups of these flies are common in the southern United States in areas with loose sandy soils. Liohippelates spp. do not bite, but because of their persistent feeding in large numbers at certain times of the year, they result in extreme annoyance to people. It has also been suggested that large populations of Liohippelates spp. can reduce weights or have other physiological effects on animals due to persistent and unrelieved feeding. In addition to annoyance, this group of flies has been implicated in the transmission of several pathogens to humans and animals including conjunctivitis (pink eye), acute bovine mastitis and vesicular stomatitis.




