In 1874, Othmar Zeidler first synthesized DDT,
dichlorodiphenyltrichloroethane, that is,
1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane, but Zeidler had not
investigated its properties. Müller spent four years testing
349 compounds before he tested DDT.
Mosquitos infect over a quarter-billion people in South
America, Asia, and Africa with malaria each year, and over a
half-million die of it.
The parasite responsible for visceral leishmaniasis (black
fever) attacks the internal organs and infects a half-million
people each year. If untreated, it usually results in death. DDT
is still used to control the sandfly whose larva carry this
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