KINGSVILLE, Texas —The City of Kingsville Health Department is taking immediate action after a mosquito pool trapped Tuesday, Aug. 4, 2026, tested positive for St. Louis Encephalitis Virus. "We are working closely with Region 11 to ensure our response effectively reduces the threat of St. Louis Encephalitis Virus transmission," Emilio Garcia, Kingsville City Health Director, said. KRIS 6What is St. Louis Encephalitis Virus? St. Louis Encephalitis Virus, or SLEV, is a mosquito-borne illness that belongs to the same family of viruses as West Nile virus. For updates on the St. Louis Encephalitis Virus response, residents can follow the official City of Kingsville Facebook page.