by Sonia Shah
In 1670, fewer than 5 percent of farms in Norfolk and Suffolk grew turnips; by 1710, more than half did. Townshend’s idea took off in malarious Essex, thanks to “the pursuit having become fashionable,” one commentator drily noted.95 Liberated from the annual cull, livestock populations grew. Between 1640 and 1730 in the Thames Valley and the uplands of Oxfordshire, flocks of sheep more than doubled in size, and the proportion of cattle herds over five animals strong grew from around a third to nearly half.96
As with the dairy cows in the American Midwest, the greater availability of cow and hog flesh attracted the interest of malarial mosquitoes. When faced with the exposed arm of a human or the flank of a calf, England’s Anopheles maculipennis bit the calf four out of five times. Hovering between home and stable in search of a meal, she flew toward the stable ninety-nine out of one hundred times. That bit of anopheline caprice cost Plasmodium dearly.97 As cows and sheep sprouted across the English countryside, malaria transmission ground to a halt. (Years later, when malariologists realized what had happened, some took to calling for “a pig under every bed” as an effective substitute for a mosquito net.98)
Between 1700 and 1850, England’s population boomed from fewer than six million to more than sixteen million,99 despite regular outbreaks of typhus, typhoid, and diptheria, waves of cholera, and widespread tuberculosis, all untreatable by the medicine of the day.100 England logged its last case of indigenous malaria in the final years of the nineteenth century.101
These stories do not appear on colorful posters about malaria, such as those that hung inside Parliament House in 2006. It’s important to project an aura of agency, of the potency of collective will against indignations like killer mosquitoes in a modern world. It helps raise money, and it makes us feel better, too, about the mastery of our tools, the depth of our commitment, the power of our technology.
The truth is, the world’s most powerful nations knowingly sacrificed whole generations to malaria’s appetites. The pathogen ran away well before anyone thought to chase it.
9. THE SPRAY-GUN WAR
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 smoldering 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.1 The previous year, more than twenty thousand British troops wearing military-issue shorts had to be hospitalized for malaria during the invasion of Sicily.2 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.3 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.”4 More than 100,000 of the 245,000 locals sickened with malaria.5
Across the United States and Europe, scientists toiled furiously to arrest the wartime spread of disease, and to find 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 first developed by Swiss scientists at the Geigy Corporation. A sample of the stuff arrived at the U.S. 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.6
DDT had many remarkable qualities. Its effect was long lasting and relatively specific, with a special malignancy for small, cold-blooded creatures.7 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.8 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.9
Older insecticides, made from flowers and metals, were difficult 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, odorless DDT, by contrast, could be synthesized in factories.10
The notion that DDT could be used to exterminate entire species of living things first arose in the mostly malaria-free United States, where fed-up farmers and gardeners continued to battle insect pests.
When the U.S. War Production Board announced that small quantities of DDT would be made available for civilian use in August 1945,11 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 $10 million in 1944, purchased mainly by the military, to over $110 million by 1951, mostly to farmers.12
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.”13 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.14 The U.S. 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.15
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, flying, burrowing billions whose numbers and depredations baffle human comprehension.”16 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 flea 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 conflated the killing technologies of DDT and the atomic bomb, dropped on Japan just five days after DDT’s public launch. Time magazine pictured Hiroshim
a’s mushroom cloud next to news about DDT’s debut.17 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.”18
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 dissatisfied. “I do not need to tell you,” he added, “that dissatisfaction breeds communism.”19 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.”20 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.”21 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.”22
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.23
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 1950.24 Also, Soper wasn’t the type to win any popularity contests. “The trouble with Soper,” noted one military official, was that “he is not only personally a stinker but he is just plain dumb.”25 Even Soper’s friend and Rocke feller colleague Paul Russell had to admit that many people described Soper “in terms I prefer not to quote.”26 American universities refused to hire him because they considered him a Fascist.27
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 $150 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.28
With the new deep pockets and friendly leadership of the UNRRA, Soper had his chance to attempt extermination on a grand scale.29 With less than $3 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.30
Local leaders thrilled at the prospects. “The future will open up a completely different life for the island’s generations,” proclaimed one commentator at the time. “The stables will be filled 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-five thousand workers doused the wild, rocky island with more than 250 tons of DDT.31
Soper’s campaign in Sardinia echoed across the globe, as a planet-wide war against insect life unfolded. Insects every where found themselves under a chemical siege. Spray crews armed with canisters of DDT drenched the walls of more than a million American homes in the U.S. South,32 and an army of pilots hired by the USDA and state officials blanketed the countryside with DDT and related compounds to exterminate fire ants, gypsy moths, sawflies, elm dark beetles, and pest mosquitoes.33 In Greece, Venezuela, Sri Lanka, Italy, and elsewhere, government officials, fed up with tedious environmental management and epidemiological sleuthing to minimize malarial mosquitoes, launched DDT assaults upon Anopheles. Trucks wafting plumes of DDT rumbled through the streets of Panama’s Canal Zone every night; local children frolicked in the chemical clouds.34
Insect populations every where crashed precipitously. Hungry insects expired in the fields unfed, and agricultural yields doubled worldwide between 1947 and 1979 (thanks, too, to synthetic fertilizers).35 In Greece, flies and lice were nowhere to be found, and the olive crop grew by 25 percent.36 As mosquito populations were decimated, so were the malaria parasites within them. In Sardinia, cases dropped from more than 75,000 in 1946 to just 9 in 1951; in Sri Lanka, from 3 million in 1946 to 7,300 in 1956. Malaria was gone entirely from the United States by 1951.37
The dramatic fall of their longtime plasmodial foe inspired a messianic zeal in malariologists such as Soper and his Rockefeller Foundation colleague Paul Russell. Cut loose from the foundation’s health division (which formally closed in 1951), Soper himself for a time headed the regional public health authority, the Pan American Sanitary Bureau (later known as PAHO, or the Pan American Health Organization).38 And he wrangled a spot for his old Brazilian colleague from the anti-gambiae campaign, Marcolino Candau, as the head of PAHO’s newly formed counterpart, the World Health Organization.39 Both he and Russell formally advised WHO,40 which agreed to dispatch teams of experts to all corners of the malarial world to preach the DDT credo. By the early 1950s, WHO experts had launched more than seventy antimalarial DDT demonstration projects in Southeast Asia alone.41
One DDT convert summed up the new ethos among the international community of malariologists at a 1950 WHO meeting. Folding his hands before him, he intoned, “Let us spray.”42
• • •
Even as the DDT hoopla reached a fever pitch, there were scientists who mused over how little, really, was known about the tenacious new compound. DDT certainly seemed benign, especially in contrast to the older, highly toxic pesticides it had replaced. It killed insects, yes, but slowly, and it had no immediate effect on humans or other creatures. It didn’t even have an odor.43
And yet its amazing persistence in the environment gave some scientists pause. Military scientists knew, from early toxicity studies, that when ingested in large enough doses, DDT could destroy small mammals such as guinea pigs and rabbits. The army’s James Simmons recalls finding the results of early DDT testing “somewhat alarming,” and “rather startling.”44 DDT’s effect “on other insect life, on pollination by insects, and on various biological balances is not well known,” warned Rockefeller’s Russell in 1945.45 “There is a great deal that is yet to be learned about how to safely use DDT,” a USDA entomologist added in The New York Times shortly after DDT’s public launch.46 Warned another government entomologist, darkly, “Biological deserts may be produced by heavy treatments of DDT.”47
The military had chosen to move forward with DDT despite its alarming toxicity profile, since the limited campaigns they were considering would never expose larger creatures to dangerously high doses—and even if they did, such collateral damage mattered little during the course of a war.48 By the time DDT came into much greater use, there was little interest in studying its impact on the environment and even less funding for such studies. With DDT fulfilling the long-held dreams of so many different sectors of society, the whole focus of entomology had shifted t
oward expanding and refining the use of pesticides, not fretting about their drawbacks or exploring possible alternatives.
Entomologists who studied non-pesticide-based methods—crop rotation, for example—were “ridiculed” by their peers as part of the “lunatic fringe,” as the historian John Perkins notes.49 And while the U.S. government required chemical companies to establish safe-use guidelines for products such as medicines, there were no such requirements for pesticides, which could be marketed to the public with virtually no prior testing.50 Of course, regulatory laxity made sense in the years prior to 1945, when the entire U.S. production of all pesticides amounted to less than one hundred million pounds of materials that nobody had any interest in applying lavishly.51 But by 1951, U.S. manufacturers produced one hundred million pounds of benign-seeming, easy-to-use DDT alone.52
And so nobody paused much to ponder the bizarre reports of insects strangely immune to DDT. In 1948, government entomologists in Orlando, Florida, had noticed that a sample of houseflies collected around local dairies seemed strangely tolerant of DDT, withstanding the toxin for much longer than other flies.53 A WHO malariologist enjoying lunch at a country inn in Greece spied an Anopheles mosquito placidly reclining on a DDT-drenched wall.54 Within a few years of DDT’s arrival, reports of unnaturally tolerant flies and strangely oblivious mosquitoes popped up in Lebanon, Saudi Arabia, Egypt, El Salvador, and Greece.55 But when scientists from the U.S. public health service discussed the reports at a meeting of the National Malaria Society in December 1948, all agreed: those bugs were outliers, freaks, mutants.56
