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Of all the infectious diseases: malaria (from the Italian mal aria, meaning 'bad air' ) has affected the most number of people. But the true cause of this disease - which is credited with bringing down the Roman Empire- was not pinpointed until the nineteenth century. The first finding was Alphonse Laveran's 1880discovery of the malaris parasite - the Plasmodium, a single-celled animal or 'protozoan'. In 1894, Patrick Mansonsuggested that the infectionmight be transmittedby mosquitoes. And in 1897Ronald Rossa Britishmedical officerworking in India, finally located in the stomachwall of an Anopheles mosquito; the eggsthat are intermediate state of the plasmodium life cycle. He devoted another year of to collecting, feeding mosquito's and dissectingthe salivary gland. Here it waits to be
injected into its humanhostwhen a female mosquito takes her blood meal.
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Unsympathetic employers hampered Ross's work in India. Transferred to a region where human malaria was scarce, he undertook ground-breaking research on the malarial parasiteof birds. In Italy, Battista Grassistole Ross's thunder by working out the full sequence of transmission in human malaria. An ugly priority dispute followed, and, amid some controversy, Ross received the 1902Nobel Prizein Physiologyor Medicinefor his work in proving the lifecycle of malaria. He is also responsible for the creation of the intellectual framework of establishing tropical medicine as a distinct speciality, prompting the search for the parasite-vector pairing often responsible for diseases rife in hot climates.
Ross was one of the many who developed measure to control malaris through the eradication of mosquitoes. The introduction of the insecticideDDTduring the Second World Warwas a great boon, and in 1955the World Health Organizationjudged the conquest of malaria an attainable goal. But the campaign was thwarted. Mosquitoes quickly became resistant to DDTand the insecticide proved to be harmful to the environment.
Categories: Protista| Parasitology
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It uses material from the http://en.wikipedia.org/wiki/Malarial+parasite Wikipedia article Malarial parasite.