What to do if you suspect New World screwworm on your farm

Due to the current outbreak of New World screwworm (NWS) in Central America and Mexico, the U.S. Department of Agriculture (USDA) is preparing for a domestic response in case NWS is discovered in the U.S.

August 4, 2025

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Courtesy USDA

Due to the current outbreak of New World screwworm (NWS) in Central America and Mexico, the U.S. Department of Agriculture (USDA) is preparing for a domestic response in case NWS is discovered in the U.S.

Sarah Speth, emerging diseases coordinator for the USDA’s Animal and Plant Health Inspection Service (APHIS) Veterinary Service, recently spoke during a webinar hosted by the National Institute for Animal Agriculture about how to spot NWS and what you should do if you suspect NWS in or on your animals.

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