Anopheles, the mosquito that carries malaria, which today kills 2 to 3 million people a year.
(Pan American Health Organization/World Health Organization )
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During the war in Europe, in 1944, we went to sleep every night while being fed upon by bedbugs and fleas, and there was no way to escape them. We had also heard about “cooties” (body lice) causing typhus, which killed more than 3 million people in Europe and vicinity during and after World War I.
One day, I was ordered to dust every soldier in our company with an insecticidal powder that had just been received. For two weeks I dusted the insecticide on soldiers and civilians, breathing the fog of white dust for several hours each day. The body lice were killed, and the DDT persisted long enough to kill young lice when they emerged from the eggs.
Fortunately, no human beings have ever been harmed by DDT. I later learned that the material was produced by a German chemist, Othmar Zeidler, in 1874. He had made hundreds of chemical compounds but he never suggested uses for any of them. Sixty years later, in Switzerland in 1939, Dr. Paul Müller was seeking chemicals that might kill insect pests, and he followed Zeidler’s written directions for preparing several compounds. One of them was a compound that Zeidler had labelled dichlorodiphenyl-trichloroethane. Müller called it “DDT,” and in 1948, he received the Nobel Prize for his work with that chemical.
Dr. Joseph Jacobs later described his role in producing the first DDT made in the United States. At Merck & Company in New Jersey, he was assigned the task of duplicating Zeidler’s procedure, but on a much larger scale. He commandeered a huge glass-lined reactor, and produced the first 500 pounds of DDT made in the United States. An Army truck rushed it to an airport, and it was flown to Italy, where it halted a developing epidemic of typhus in our troops. The Surgeon General telegrammed thanks from President Roosevelt, and stating: “It is estimated that 5,000 lives were probably saved by destroying the typhus-carrying body lice infesting our soldiers.”1
After the war, I entered Ohio State University to study entomology. Insects are the most abundant forms of life on Earth; fortunately, only about 1 percent of them compete with human beings for food, fiber, and space. A small part of that 1 percent threatens our health with stings or bites, and a few transmit serious diseases.
I received my Ph.D. for research on beetles, and was hired to teach entomology at San Jose State University in California. There I spent much time studying parasitic insects, and taught medical entomology courses for more than 30 years. In addition to louse-borne typhus, our students were required to learn about diseases caused by mites, ticks, fleas, kissing bugs, black flies, chiggers, sand flies, eye gnats, tsetse flies, and mosquitoes.
At least 80 percent of human infectious diseases are arthropod-borne—transmitted by insects, mites, or ticks.2 They have caused the death of hundreds of millions of people by infecting them with the pathogens that cause typhus, bubonic plague, yellow fever, malaria, dengue fever, sleeping sickness, encephalitis, elephantiasis, leishmaniasis, and yaws. During the 1960s, the World Health Organization proposed the possible eradication of malaria, worldwide, and malaria control was achieved in areas with a population of 279 million people. Thirty-six formerly malarious countries totally eradicated the disease. The U.S. National Academy of Sciences stated in 1970: