Malaria
JULY 2007
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Malaria
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By Michael Finkel
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Photographs by John Stanmeyer
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The idea is based on research done in the late 1960s at New York University by Ruth Nussenzweig, who demonstrated that parasites weakened by radiation can prompt an immune response in mice without causing malaria. Hoffman's vaccine will deliver the wallop of a thousand mosquito bites and, he says, produce a complete protective response. Thereafter, any time the vaccinated person is bitten by a malaria-carrying mosquito, the body, already in a state of alert, will not allow the disease to take hold.
Hoffman's lofty goal is to eventually immunize all 25 million infants born in sub-Saharan Africa every year. He believes that at least 90 percent of them will be protected completely from malaria. If so, they'll be the first generation of Africans, in all of human history, not to suffer from the disease.
But which generation will it be? Although Sanaria's vaccine may undergo initial field-testing next year, a federally approved version won't be available for at least five years—and maybe never. Given the track record of malaria vaccines, that's a distinct possibility. After so many million years on Earth and so many victories over humanity, the disease, it is certain, will not surrender easily.
When it comes to malaria, only one thing is guaranteed: Every evening in the rainy season across much of the world, Anopheles mosquitoes will take wing, alert to the odors and warmth of living bodies. A female Anopheles needs to drink blood every three days. In a single feeding, which lasts as long as ten minutes, she can ingest about two and a half times her pre-meal weight—in human terms, the equivalent of downing a bathtub-size milk shake.
If she happens to feed on a person infected with malaria, parasites will accompany the blood. Two weeks later, when the mosquito flies through the open window of a mud hut, seeking her next meal, she'll be loaded.
Inside the hut, a child is sleeping with her sister and parents on a blanket spread over the floor. The family is aware of the malaria threat; they know of the rainy season's dangers. They've hung a bed net from the ceiling. But it's a steamy night, and the child has tossed and turned a few times before dropping back to sleep. Her foot is sticking out of the net. The mosquito senses it, and dips down for a silent landing.
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