Charles Louis Alphonse Laveran was a French physician and parasitologist who won the Nobel Prize in Physiology or Medicine in 1907 for his discoveries about the transmission of malaria. Laveran identified the protozoan parasite responsible for malaria in the blood of infected humans, proving that the disease was caused by a specific parasite transmitted through mosquitoes. His groundbreaking work significantly advanced the understanding and treatment of malaria, a disease that had a profound impact on global health.