In a new study seeking to answer how Culicoides biting maintain transmission of bluetongue virus to cattle in temperate regions year after year, researchers conducted extensive collections of host-seeking midges during winter (November to April) over a period of three years in the Chino dairy region of southern California. On the warmest day during each trapping week, carbon dioxide traps such as the one shown here were set up throughout the dairy region to capture host-seeking midges active on that date. (Photo by Xinmi Zhang, Ph.D.)