Mosquitos that carry West Nile are becoming resistant to insecticides, CDC says By Erika Edwards, July 29, 2023 A report by NBC News discussed a visit with the Center for Disease Control’s (CDC) insect lab in Colorado. One growing concern for health officials is West Nile virus, as mosquitos that carry the disease are growing read more NBC News Report: Mosquitos that carry West Nile are becoming resistant to insecticides, CDC says