Nott was not the first to suggest insects as a possible cause for yellow fever. But he was among a very tiny number over a long period of time, and he was more insistent than previous writers. Nevertheless, it would be decades before the claim was taken seriously. Yellow fever was considered akin to malaria in the sense that it was caused by bad air and poor sanitation. The notion that “malaria” was caused by “bad air” was so deeply rooted in the minds of people that it was buried in the word itself: mal-aria.William Crawford Gorgas is somewhat like Norman Ernest Borlaug; men to whom hundreds of millions owe their lives and yet are virtually unknown to the modern generation.
Fast forward to the Havana, Cuba of 1901. By this time researchers had all-but-proven that yellow fever and malaria were spread by mosquitos (although doubters were still more far numerous than believers). By then, William Crawford Gorgas was a military doctor and a specialist in yellow fever. Notably, he was not among those who believed in the mosquito “theory.” Nevertheless, he thought it was worth a try and used Havana as a proving ground for the theory. His campaign of eradication turned out to be astonishingly effective. Efforts to get rid of the mosquito culprits essentially eradicated yellow fever and came close to eradicating malaria in Havana.
Because of his success, Gorgas was chosen to be the sanitary officer for the Panama Canal project. Building a canal there would have been an extraordinary feat of engineering even if disease were not a problem. But, if anything, disease was the more difficult problem. During the 1880s, the French, led by Ferdinand de Lesseps (then fresh from building the longer, but otherwise less challenging, Suez Canal) had already failed in large part because of the horrific rates of yellow fever and malaria. Without Gorgas—who faced superiors who continued to doubt the mosquito theory—the Americans would have done no better.
Gorgas knew that yellow fever mosquitos (now called the aedes aegypti) lay their eggs only in fairly clean standing water and that they live only near human beings (their favorite prey). He set about getting rid of standing water wherever it could be found near humans. And it was nearly everywhere. Hospital bed legs were in pans of water to keep the ants away. Rain barrels collected fresh water for each household, and it was commonly stored indoors in earthenware pots. Those pans, barrels and pots were often teeming with tiny larvae. His staff members went door to door getting rid of standing water or covering it with a thin layer of oil. Citronella, screens, netting and fumigation were put to use.
It worked magnificently. Yellow fever cases plummeted. After late 1906, there were no further deaths.
Malaria was harder, since the anopheles genus of mosquito is more widespread. Swamps had to be drained, brush and trees cut, and a carbolic acid larvicide spread liberally. Workers were given prophylactic quinine. Many were put to work killing individual anopheles inside buildings with swatters. While malaria was not conquered entirely, the workforce hospitalization rate for malaria went from an astonishing 9.6% in 1905 to 1.6% in 1909.
Friday, October 5, 2018
Never has so much been owed by some many to so few
From On this day in 1854, William Crawford Gorgas, who fought yellow fever and malaria at the Panama Canal, was born by Gail Heriot
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