Screwworms in US: Human risk is low—but they can burrow through your skull

The US Department of Agriculture confirmed three new cases of New World screwworms this week, bringing the total to five. One case involves a dog in New Mexico, with its infection reported in Texas, and potential recent travel to Mexico where the flies are also spreading. The other four US cases are in calves in Texas, with two in Zavala County and two in La Salle County. The primary concern is the threat to livestock, particularly cattle, and the associated financial risks to the cattle industry. The USDA estimates that a widespread resurgence of screwworms, similar to past outbreaks, could cost Texas producers $732 million annually and the Texas economy $1.8 billion. The larvae of these flesh-eating flies can be fatal to cattle if left untreated, necessitating rigorous prevention measures.