tary medicine. In it he challenged the traditional wisdom regarding malaria’s ecology—namely, that the disease was restricted to low-lying humid plains. Laveran noted that malaria also could occur in temperate zones, and that not all tropical areas were plagued by the disease. Although malaria had been linked with swamps ever since the condition known as Roman fever inspired the name mal’aria (“bad air”), Laveran knew from contemporary scientific articles that many diseases previously ascribed to miasmas, or evil vapors, were in fact caused by microbes. Thus he predicted: “Swamp fevers are due to a germ” (Jarcho, 1984).

After transferring to a new post on Algeria’s North African coast, Laveran investigated his theory. On October 20, 1880, while looking through a crude microscope at the blood of a febrile soldier, he saw crescent-shaped bodies that were nearly transparent except for one small dot of pigment. In preceding decades the brownish-black pigment hemozoin (now known to be the product of hemoglobin digestion by the malaria parasite) had been found in cadaveric spleens and blood of malaria victims by several investigators including Meckel, Virchow, and Frerichs. Laveran subsequently examined blood specimens from 192 malaria patients and saw pigment-containing crescents in 148 sufferers (Laveran, 1978). He ultimately recognized four distinct forms in human blood that would prove to be the malaria parasite in different stages of its life cycle: the female and male gametocyte, schizont and trophozoite stages.

Although his findings were initially viewed with skepticism, 6 years later, Laveran was affirmed. Camillo Golgi (1843-1926) linked the rupture and release of asexual malaria parasites from blood schizonts with the onset of every third- and fourth-day fever due to P. vivax and P. malariae, respectively. Golgi was awarded the Nobel Prize in 1906 for unrelated studies of the central nervous system. One year later, Laveran received the Nobel Prize for discovering the single-celled protozoan that caused malaria.

Discovering Malaria’s Mosquito Stages

August 20, 1897, is the original “Mosquito Day”—so named by Surgeon-Major Ronald Ross (1857-1932) of the British Indian Medical Service. Although Ross had previously spent more than a year fruitlessly studying gray and brindled mosquitoes (probably Culex fatigans and Aedes aegypti, respectively) incapable of hosting malaria, on that date he discovered a clear, circular body containing malarial pigment in a dapple-winged Anopheles mosquito that had previously fed on an infected patient. The next day the doctor-cum-poet/composer/mathematician, who struggled to pass his own medical exams, dissected another Anopheles mosquito that had siphoned blood from the same patient on the same day. This time Ross observed even larger pigment-containing bodies. Convinced that malaria



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