Culex (also called the common house mosquito) is a genus of mosquitoes. It includes several species of mosquitoes that vector (carry and transmit) one or more important diseases between birds, humans and other animals. The diseases they vector include West Nile virus, as well as arbovirus and filariasis infections. A connection between Culex mosquitoes and malaria was first shown by Major Ronald Ross of the British Army. Ross received a Nobel Prize in Physiology or Medicine in 1902 for his work.