New World Screwworm Identified in Domestic Animals in New Mexico and Texas

On June 3, 2026, New World Screwworm (NWS), a parasitic fly whose larvae feed on living tissue and can infest mammals and birds, was identified in a Texas cow.  NWS has not been found in livestock, pets, wildlife or in the environment in Pennsylvania (PA).  In addition, no locally acquired cases of NWS infestation in humans have been identified in the U.S. The risk to human health in the U.S. remains very low.  Read more.