Who discovered that the malaria parasite is transmitted by mosquitoes?

Ronald Ross discovered that malaria parasites are transmitted by mosquitoes. In 1897, while serving in the Indian Medical Service, Ross found pigmented malaria parasites in the gut of mosquitoes that had fed on infected blood. This provided crucial evidence that mosquitoes were not merely associated with malaria outbreaks but acted as vectors carrying the parasite between hosts.

Ross later used birds infected with malaria parasites to trace more of the parasite’s life cycle. In 1898, he showed that mosquitoes could acquire the parasite from an infected bird and transmit it to another. His work established the mosquito stage of malaria transmission and helped create modern mosquito-control strategies.

A common mix-up involves Patrick Manson, who suggested that mosquitoes might transmit malaria and strongly influenced Ross. Giovanni Battista Grassi later demonstrated important details of human malaria transmission through Anopheles mosquitoes. Ross received the 1902 Nobel Prize in Physiology or Medicine for his malaria research.