One final observation on our great post-war successes in controlling malaria by targeting its vector, the Anopheles mosquito. By using that most marvelous insecticide DDT, we were beginning to gain the upper hand in our conquest of malaria as clearly demonstrated in the table below.
Country
|
Malaria occurrence per annum prior to introduction of DDT
|
Malaria occurrence per annum after the introduction of DDT
|
Sardinia
|
75,000 (1946)
|
9 (1951)
|
Turkey
|
1,188,969 (1950)
|
2,173 (1969)
|
India
|
ca 75 million (1946)
|
ca 750,000 (1969)
|
Taiwan
|
>1 million (1950)
|
9 (1969)
|
Venezuela
|
817,115 (1943)
|
800 (1958)
|
Sri Lanka
|
2.8 million (1946)
|
17 (1963)
|
Sri Lanka
|
2.8 million (1946)
|
2.5 million (1969) after DDT was banned, which is what we like to call progress
|
As can be seen, vector control for infectious diseases can be remarkably effective in stopping plagues. WHO estimates that between 1946 and 1966, 100 million people living in the malaria belt around the world were saved as a result of the widespread use of DDT for mosquito control. Unfortunately, DDT was banned and malaria re-emerged as a major global plague. We got to “save the World,” and tens of millions of people we don’t care about got to bury their children, parents and friends over the next 50 years.
A new biological control approach involving technology called gene drives has the potential to wipe malaria from the earth. These genetically modified organisms (GMOs), Anopheles mosquitoes, are genetically altered in such a way that successful mating leads to nonviable offspring. These mutant mosquitos can be bred and released into the environment where their futile mating could lead to total collapse of their populations around the world. This approach can certainly lead to terminal extinction of all arthropod diseases vectors. Hopefully we will not blow it this time.
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