The newest weapon against malaria comes from the most unlikely of places—the guts of a mosquito. Johns Hopkins University microbiologist George Dimopoulos discovered that a class of Enterobacter bacteria living inside some Zambian mosquitoes makes the insects resistant to Plasmodium falciparum, a parasite that causes malaria.
When the two microbes squared off in a petri dish, the gut bacteria could almost totally prevent Plasmodium from growing. Mosquitoes that sucked up both the bacteria and the parasite were unable to transmit malaria. Dimopoulos found that the bacteria unleash a torrent of unstable oxygen molecules that inhibit Plasmodium’s development. Those molecules, he believes, are either natural waste products or chemical weapons that are normally used against rival bacteria. The fact that they kill Plasmodium is a happy accident, and one that Dimopoulos wants to exploit. “The idea is to feed mosquitoes in the field with an artificial nectar supplemented with the bacterium,” he says. “It would be like a probiotic for the mosquito.”
Mosquitoes need to ingest only a small amount of the Enterobacter bacteria to become resistant to malaria, so the probiotic could potentially be deployed en masse. Used strategically throughout the tropical world, the bacteria could become a practical tool in the fight against malaria, helping to stop mosquitoes from spreading the disease to some of the 250 million people worldwide who currently contract it every year.