World Mosquito Day
World Mosquito Day, observed annually on 20 August, is a commemoration of British doctor Sir Ronald Ross's discovery in 1897 that female mosquitoes transmit malaria between humans. Ross is responsible for the annual observance, having declared shortly after his discovery that the day should be known as World Mosquito Day in the future.
The London School of Hygiene & Tropical Medicine holds Mosquito Day celebrations every year, including events such as parties and exhibitions, a tradition dating back to as early as the 1930s.