Largest U.S. Screwworm Cluster in Texas Since Initial Detection

A cluster of four New World screwworm cases on a single property in Terrell County, Texas, has become the largest reported in the U.S. since the parasite was detected earlier this month. The U.S. Department of Agriculture confirmed three cattle and one goat on the same premises tested positive for screwworm, marking the first major outbreak in livestock in nearly 50 years. The total number of confirmed cases in the U.S. has now reached 20 since early June, when the parasite was initially found in a calf in Zavala County, Texas. A separate bovine case was reported in Medina County on June 24, further expanding the outbreak. The screwworm, a parasitic fly whose larvae burrow into the wounds of warm-blooded animals, poses no threat to food safety but can cause severe health issues or death in livestock if left untreated. The infestation typically spreads through the movement of infested animals. Officials from the Texas Animal Health Commission stated that epidemiological investigations and tracebacks are ongoing to determine the source of the infestations. Quarantines are currently in effect across parts of more than a dozen Texas counties, as authorities work to contain the spread. The outbreak comes at a critical time for the U.S. cattle industry, which is already grappling with a shrinking national herd.