FDA authorizes additional screwworm medications for emergency use

The U.S. Food and Drug Administration announced that it has granted emergency use authorizations for several new medications aimed at preventing and treating infestations of the flesh‑eating New World screwworm (Cochliomyia hominivorax). The screwworm, which has recently been detected along the U.S.–Mexico border, can cause severe tissue damage in livestock and occasionally in humans, prompting urgent regulatory action. The authorized drugs—comprising insect growth regulators and topical repellents—are intended for use on cattle and other susceptible animals in high‑risk areas, with the goal of curbing the spread of the parasite and protecting the livestock industry.

This regulatory decision follows a series of surveillance reports that confirmed the screwworm’s presence in new locations, raising concerns about potential economic losses and animal welfare. By making these treatments available under emergency use, the FDA seeks to provide immediate tools for farmers and veterinarians to manage infestations while longer‑term control measures, such as sterile insect technique programs, are expanded. The authorizations are expected to help mitigate the screwworm’s impact on the border region and support the broader effort to prevent the parasite’s further dissemination into the United States.