US escalates response to New World screwworm outbreak

Federal authorities have initiated a scaled-up response to the first detection of New World screwworm in the U.S. in a decade. The Centers for Disease Control and Prevention (CDC) has activated a formal emergency response to investigate the outbreak and prepare for potential human exposure. Agriculture Secretary Brooke Rollins stated that this action allows for the deployment of additional federal resources.

Concurrently, the Food and Drug Administration (FDA) has granted emergency use authorization for nitenpyram, a generic over-the-counter tablet, marking the first generic animal drug approved to treat New World screwworm in dogs and cats. To date, seven cases have been confirmed across Texas and New Mexico, involving cattle, a goat, and a dog.

New World screwworm is a parasitic fly whose larvae feed on the living tissue of warm-blooded animals, entering through open wounds and burrowing into flesh. If not detected and treated promptly, it can cause severe suffering and wounds in animals. The parasite was previously eradicated in the U.S. in the 1960s, with the most recent outbreak occurring in Florida between 2016 and 2017. While endemic in South America and the Caribbean, human infections are rare, and no U.S. cases have been reported in the current outbreak.