The history of mankind's battle against malaria has been long and largely ineffectual. The Fever looks at the rise of DDT in post-WWII America.
For most of humankind's history with malaria, political indifference, scientiﬁc controversy, and tightfistedness have reigned. The post–World War II development of a potent new compound called dichlorodiphenyltrichloroethane — or simply DDT — changed all that.
DDT unloosed the leash that had held us back, turning on its head every calculation about malaria and our ability to challenge it. A smouldering new collective resolve emerged. Political and scientific leaders from around the globe decided, en masse, to abandon its partial solutions: to stop trying to diminish malaria's burden, give up attempting to slow its progress or soften the suffering of its victims. Like some long-tormented creature exploding into a violent howl, they declared a fight to the finish. They'd use DDT to wipe Plasmodium off the face of the Earth.
The outburst didn't last for long. But it changed the landscape of malaria forever.
Malaria had been a particular problem on the tropical battlefields of World War II. "Never before has this great disease predator had such an unsurpassed opportunity," complained one military oﬃcial, in a 1944 issue of Science magazine. The previous year, more than twenty thousand British troops wearing military-issue shorts had to be hospitalised for malaria during the invasion of Sicily. At Bataan, in New Guinea, and in Guadalcanal, malaria sickened tens of thousands of troops, grounding whole divisions, felling more soldiers than enemy combat.
The German army purposely triggered malaria epidemics, such as in Italy in 1944. Drainage pumps on the Roman marshes ordinarily pumped excess water out to sea, desiccating the land enough to make it malaria-free and thus habitable for thriving cities and towns. By stilling the pumps, the Germans could have flooded the region and effectively impeded the Allies' progress. But German malariologist Erich Martini had studied the habits of the local malaria vector, Anopheles labranchiae, in depth, and he knew that inundating the region with the Mediterranean's salty waters would allow A. labranchiae, which can thrive in brackish water, to flourish. And so rather than simply stopping the pumps, they reversed them, salinating some ninety-eight thousand acres. Then they confiscated local stockpiles of antimalarial drugs. As the German soldiers departed, they left behind "clever sketches," The New York Times reported in 1944, "of the plague of mosquitoes that would follow the flooding of the farmlands." More than 100,000 of the 245,000 locals sickened with malaria.
Across the United States and Europe, scientists toiled furiously to arrest the wartime spread of disease, and to ï¬nd new products to replace those made inaccessible by the war. Among the new synthetic chemicals they unleashed was a range of insect killers that included an amazingly resilient compound made of carbon, hydrogen, and chlorine, a recipe ï¬rst developed by Swiss scientists at the Geigy Corporation. A sample of the stuï¬€ arrived at the US Department of Agriculture's entomology research station in Orlando, Florida, in the early 1940s, for testing. "Nothing had been seen like this before," remembers one malariologist.
DDT had many remarkable qualities. Its effect was long lasting and relatively specific, with a special malignancy for small, cold-blooded creatures. In DDT's presence, neurons would start to fire spasmodically, oblivious to countersignals from the brain, like an engine running without a driver. Jitters led to convulsions, which, if the dose was high enough, ended in death. It wouldn't dissolve in water, which meant that DDT powder, even if sprinkled on human skin or inhaled, had no discernible effect on people. It also meant that it could persist in the environment, exerting its poisonous effect, for months.
Older insecticides, made from flowers and metals, were diffcult to produce, short-acting, and often so toxic they had to be arduously applied in small quantities by hand, for fear they'd destroy everything, not just weeds and pests. Safer, odourless DDT, by contrast, could be synthesised in factories.
The notion that DDT could be used to exterminate entire species of living things firrst arose in the mostly malaria-free United States, where fed-up farmers and gardeners continued to battle insect pests.
When the US War Production Board announced that small quantities of DDT would be made available for civilian use in August 1945, everyone from homemakers to farmers to government officials jostled for a piece of DDT's diabolical magic. Gardeners and farmers were "raiding the stores for every can that shows its top above the counter," writes the medical historian James Whorton. DDT sales skyrocketed from $US10 million in 1944, purchased mainly by the military, to over $US110 million by 1951, mostly to farmers.
And they loved it. "Never in the history of entomology," enthused the USDA's Sievert Rohwer, "has a chemical been discovered that offers such promise to mankind for relief from his insect problems as DDT." The New York Times lauded the "Army's insect powder" as a magical compound "deadly to insects" and "harmless to man." Others likened DDT to lifesaving penicillin. The US secretary of agriculture proclaimed his dream that DDT and other insecticides might be seeded inside clouds, so that the chemicals would shower down with the rain.
Why not? Americans eager for a taste of wartime glory could pursue insects to extermination, just as the Allies did the Nazis and the Japanese. The DDT war on insects would be "our next world war," Popular Mechanics announced, "a long and bitter battle to crush the creeping, wriggling, ï¬‚ying, burrowing billions whose numbers and depredations baffle human comprehension." After all, noted the chief of the Chemical Warfare Service, "the fundamental principles of poisoning Japanese, insects, rats, bacteria and cancer are essentially the same." (The Nazi propagandist Joseph Goebbels had used a similar rationale. "Since the ï¬‚ea is not a pleasant animal we are not obliged to keep it... our duty is rather to exterminate it," he said. "Likewise with the Jew.")
And the news media and government agencies often confiscated the killing technologies of DDT and the atomic bomb, dropped on Japan just five days after DDT's public launch. Time magazine pictured Hiroshima's mushroom cloud next to news about DDT's debut. The CDC published the same mushroom cloud on the cover of one of its publications, too, specifically to illustrate DDT's awesome powers, calling it "the atomic bomb of the insect world".
In popular films and plays such as the 1948 radio play Leinengen versus the Ants (made into a film starring Charlton Heston in 1954) and the 1954 film Them! filmmakers portrayed insects as mindless mass killers overrunning the countryside just as Americans feared that Communists, Nazis, and other totalitarian types might. Insects were "an evil force," a member of the House of Representatives said, one that made people dissatisï¬ed. "I do not need to tell you," he added, "that dissatisfaction breeds communism." Exterminating commie pinko insects with DDT, in other words, became downright patriotic.
Insects' critical role in decomposition and pollination forgotten, entomologist E. O. Essig proclaimed in 1944 that "insects are enemies of man." Why tolerate them at all? DDT had ushered in an "auspicious time," said the entomologist Clay Lyle in a 1947 address to a professional entomologists' society, for "determined campaigns" for "complete extermination". The makers of DDT agreed. So did government entomologists. "We have the tools," the USDA's M. L. Clarkson told a congressional subcommittee, "to bring this to a final conclusion."
DDT similarly inspired Rockefeller Foundation malariologists to ratchet up their own battles against malarial mosquitoes. For years, Lewis Hackett and others had been promoting the utility of attacks on mosquitoes. So had the forbidding Rockefeller malariologist Fred Soper. But Soper didn't believe in merely controlling mosquito populations, depressing their numbers sufficiently for malaria to decline or even die out, as Hackett did. He felt that every mosquito could — and should — be exterminated altogether. He'd done just that, he claimed, in Egypt and Brazil in the 1930s, both of which had been invaded by Anopheles gambiae mosquitoes from Africa. Soper boasted that he'd "annihilated" and "completely eradicated" the foreign mosquito, using the agricultural insecticide Paris Green. He felt that DDT, which he considered an "almost perfect insecticide," could be used for even grander mosquito-eradication schemes.
Before the war, however, Soper had had only limited reach into global malaria territory. Brazil's Fascist leader, Getúlio Vargas, had acquiesced to Soper's methods, but elsewhere, authorities tended to resist his bold interventions. For one thing, his claims were exaggerated: ecological shifts probably played a role in limiting A. gambiae's spread in Brazil, and A. gambiae had returned to Egypt by 1950.
Also, Soper wasn't the type to win any popularity contests. "The trouble with Soper," noted one military oï¬ƒcial, was that "he is not only personally a stinker but he is just plain dumb." Even Soper's friend and Rockefeller colleague Paul Russell had to admit that many people described Soper "in terms I prefer not to quote." American universities refused to hire him because they considered him a Fascist.
But then, in 1944, the Allied victors established a new international agency, endowed with billions of dollars, to oversee a massive relief effort in places ravaged by the war. The United Nations Relief and Rehabilitation Administration (UNRRA) had over $US150 million to fund medical work alone. And to direct the effort, the agency tapped Soper's boss, the head of the Rockefeller Foundation's health division.
With the new deep pockets and friendly leadership of the UNRRA, Soper had his chance to attempt extermination on a grand scale. With less than $US3 million and two years, he proposed, he would rid the entire island of Sardinia of every last specimen of the local malaria vector, Anopheles labranchiae.
Local leaders thrilled at the prospects. "The future will open up a completely diï¬€erent life for the island's generations," proclaimed one commentator at the time. "The stables will be ï¬lled with herds... the soil will become more fertile and the humus will give the cultivator all the fruits he deserves."
The campaign started in 1946. Sixty-ï¬ve thousand workers doused the wild, rocky island with more than 250 tons of DDT.
"The Spray-Gun War" excerpt from The Fever: How Malaria Has Ruled Humankind for 500,000 Years by Sonia Shah. The Fever copyright Â© 2010 by Sonia Shah. First hardcover edition published by Sarah Crichton Books, an imprint of Farrar, Straus and Giroux. A paperback edition published by Picador. Used by permission of Picador/Farrar, Straus and Giroux.
Sonia Shah is a science writer and critically acclaimed author.
The Fever: How Malaria Has Ruled Humankind for 500,000 Years is available through Amazon.
Image: Getty Images/Orlando, George Konig