Malaria is a confounding disease—often, it seems, contradictory to logic. Curing almost all malaria cases can be worse than curing none. Destroying fragile wetlands, in the world of malaria, is a noble act. Rachel Carson, the environmental icon, is a villain; her three-letter devil, DDT, is a savior. Carrying a gene for an excruciating and often fatal blood disorder, sickle-cell anemia, is a blessing, for it confers partial resistance to falciparum. Leading researchers at a hundred medical centers are working on antimalarial medicines, but a medicinal plant described 1,700 years ago may be the best remedy available. "In its ability to adapt and survive," says Robert Gwadz, who has studied malaria at the National Institutes of Health, near Washington, D.C., for almost 35 years, "the malaria parasite is a genius. It's smarter than we are."
The disease has been with humans since before we were human. Our hominin ancestors almost certainly suffered from malaria. The parasite and the mosquito are both ancient creatures—the dinosaurs might have had malaria—and this longevity has allowed the disease ample time to exploit the vulnerabilities of an immune system. And not just ours. Mice, birds, porcupines, lemurs, monkeys, and apes catch their own forms of malaria. Bats and snakes and flying squirrels have malaria.
Few civilizations, in all of history, have escaped the disease. Some Egyptian mummies have signs of malaria. Hippocrates documented the distinct stages of the illness; Alexander the Great likely died of it, leading to the unraveling of the Greek Empire. Malaria may have stopped the armies of both Attila the Hun and Genghis Khan.
The disease's name comes from the Italian mal'aria, meaning "bad air"; in Rome, where malaria raged for centuries, it was commonly believed that swamp fumes produced the illness. At least four popes died of it. It may have killed Dante, the Italian poet. George Washington suffered from malaria, as did Abraham Lincoln and Ulysses S. Grant. In the late 1800s, malaria was so bad in Washington, D.C., that one prominent physician lobbied—unsuccessfully—to erect a gigantic wire screen around the city. A million Union Army casualties in the U.S. Civil War are attributed to malaria, and in the Pacific theater of World War II casualties from the disease exceeded those from combat. Some scientists believe that one out of every two people who have ever lived have died of malaria.
The first widely known remedy was discovered in present-day Peru and Ecuador. It was the bark of the cinchona tree, a close cousin of coffee. Local people called the remedy quina quina (bark of barks)—and it was later distributed worldwide as quinine. Word of the medicine, spread by Jesuit missionaries, reached a malaria-ravaged Italy in 1632, and demand became overwhelming. Harvested by indigenous laborers and carried to the Pacific coast for shipment to Europe, the bark sold for a fortune.
Several expeditions were dispatched to bring seeds and saplings back to Europe. After arriving in South America, the quinine hunters endured a brutal trek through the snow-choked passes of the Andes and down into the cloud forests where the elusive tree grew. Many perished in the effort. And even if the quinine hunters didn't die, the plants almost always did. For 200 years, until the cinchona tree was finally established on plantations in India, Sri Lanka, and Java, the only way to acquire the cure was directly from South America.
Quinine, which disrupts the malaria parasites' reproduction, has saved countless lives, but it has drawbacks. It is short-acting, and if taken too frequently can cause serious side effects, including hearing loss. In the 1940s, however, came the first of two extraordinary breakthroughs: A synthetic malaria medicine was introduced. The compound was named chloroquine, and it was inexpensive, safe, and afforded complete, long-lasting protection against all forms of malaria. In other words, it was a miracle.
The second innovation was equally miraculous. Swiss chemist Paul Müller discovered the insecticidal power of a compound called dichloro-diphenyl-trichloroethane, better known as DDT. Müller was awarded the 1948 Nobel Prize in medicine for his discovery, for nothing in the history of insect control had ever worked like DDT. Microscopic amounts could kill mosquitoes for months, long enough to disrupt the cycle of malaria transmission. It lasted twice as long as the next best insecticide, and cost one-fourth as much.
Armed with the twin weapons of chloroquine and DDT, the World Health Organization in 1955 launched the Global Malaria Eradication Programme. The goal was to eliminate the disease within ten years. More than a billion dollars was spent. Tens of thousands of tons of DDT were applied each year to control mosquitoes. India, where malaria had long been a plague, hired 150,000 workers, full-time, to spray homes. Chloroquine was widely distributed. It was probably the most elaborate international health initiative ever undertaken.
The campaign was inspired by early successes in Brazil and the United States. The U.S. had recorded millions of malaria cases during the 1930s, mostly in southern states. Then an intensive antimalaria program was launched. More than three million acres (1.2 million hectares) of wetlands were drained, DDT was sprayed in hundreds of thousands of homes, and in 1946 the Centers for Disease Control was founded in Atlanta specifically to combat malaria.
America's affluence was a major asset. Almost everyone could get to a doctor; windows could be screened; resources were available to bulldoze mosquito-breeding swamps. There's also the lucky fact that the country's two most common species of Anopheles mosquitoes prefer feeding on cattle rather than humans. By 1950, transmission of malaria was halted in the U.S.
The global eradication effort did achieve some notable successes. Malaria was virtually wiped out in much of the Caribbean and South Pacific, from the Balkans, from Taiwan. In Sri Lanka, there were 2.8 million cases of malaria in 1946, and a total of 17 in 1963. In India, malaria deaths plummeted from 800,000 a year to scarcely any.
The disease has been with humans since before we were human. Our hominin ancestors almost certainly suffered from malaria. The parasite and the mosquito are both ancient creatures—the dinosaurs might have had malaria—and this longevity has allowed the disease ample time to exploit the vulnerabilities of an immune system. And not just ours. Mice, birds, porcupines, lemurs, monkeys, and apes catch their own forms of malaria. Bats and snakes and flying squirrels have malaria.
Few civilizations, in all of history, have escaped the disease. Some Egyptian mummies have signs of malaria. Hippocrates documented the distinct stages of the illness; Alexander the Great likely died of it, leading to the unraveling of the Greek Empire. Malaria may have stopped the armies of both Attila the Hun and Genghis Khan.
The disease's name comes from the Italian mal'aria, meaning "bad air"; in Rome, where malaria raged for centuries, it was commonly believed that swamp fumes produced the illness. At least four popes died of it. It may have killed Dante, the Italian poet. George Washington suffered from malaria, as did Abraham Lincoln and Ulysses S. Grant. In the late 1800s, malaria was so bad in Washington, D.C., that one prominent physician lobbied—unsuccessfully—to erect a gigantic wire screen around the city. A million Union Army casualties in the U.S. Civil War are attributed to malaria, and in the Pacific theater of World War II casualties from the disease exceeded those from combat. Some scientists believe that one out of every two people who have ever lived have died of malaria.
The first widely known remedy was discovered in present-day Peru and Ecuador. It was the bark of the cinchona tree, a close cousin of coffee. Local people called the remedy quina quina (bark of barks)—and it was later distributed worldwide as quinine. Word of the medicine, spread by Jesuit missionaries, reached a malaria-ravaged Italy in 1632, and demand became overwhelming. Harvested by indigenous laborers and carried to the Pacific coast for shipment to Europe, the bark sold for a fortune.
Several expeditions were dispatched to bring seeds and saplings back to Europe. After arriving in South America, the quinine hunters endured a brutal trek through the snow-choked passes of the Andes and down into the cloud forests where the elusive tree grew. Many perished in the effort. And even if the quinine hunters didn't die, the plants almost always did. For 200 years, until the cinchona tree was finally established on plantations in India, Sri Lanka, and Java, the only way to acquire the cure was directly from South America.
Quinine, which disrupts the malaria parasites' reproduction, has saved countless lives, but it has drawbacks. It is short-acting, and if taken too frequently can cause serious side effects, including hearing loss. In the 1940s, however, came the first of two extraordinary breakthroughs: A synthetic malaria medicine was introduced. The compound was named chloroquine, and it was inexpensive, safe, and afforded complete, long-lasting protection against all forms of malaria. In other words, it was a miracle.
The second innovation was equally miraculous. Swiss chemist Paul Müller discovered the insecticidal power of a compound called dichloro-diphenyl-trichloroethane, better known as DDT. Müller was awarded the 1948 Nobel Prize in medicine for his discovery, for nothing in the history of insect control had ever worked like DDT. Microscopic amounts could kill mosquitoes for months, long enough to disrupt the cycle of malaria transmission. It lasted twice as long as the next best insecticide, and cost one-fourth as much.
Armed with the twin weapons of chloroquine and DDT, the World Health Organization in 1955 launched the Global Malaria Eradication Programme. The goal was to eliminate the disease within ten years. More than a billion dollars was spent. Tens of thousands of tons of DDT were applied each year to control mosquitoes. India, where malaria had long been a plague, hired 150,000 workers, full-time, to spray homes. Chloroquine was widely distributed. It was probably the most elaborate international health initiative ever undertaken.
The campaign was inspired by early successes in Brazil and the United States. The U.S. had recorded millions of malaria cases during the 1930s, mostly in southern states. Then an intensive antimalaria program was launched. More than three million acres (1.2 million hectares) of wetlands were drained, DDT was sprayed in hundreds of thousands of homes, and in 1946 the Centers for Disease Control was founded in Atlanta specifically to combat malaria.
America's affluence was a major asset. Almost everyone could get to a doctor; windows could be screened; resources were available to bulldoze mosquito-breeding swamps. There's also the lucky fact that the country's two most common species of Anopheles mosquitoes prefer feeding on cattle rather than humans. By 1950, transmission of malaria was halted in the U.S.
The global eradication effort did achieve some notable successes. Malaria was virtually wiped out in much of the Caribbean and South Pacific, from the Balkans, from Taiwan. In Sri Lanka, there were 2.8 million cases of malaria in 1946, and a total of 17 in 1963. In India, malaria deaths plummeted from 800,000 a year to scarcely any.
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