Curing the Mosquito

A QUANTUM OF SCIENCE

How can bacteria help protect humans from malaria?

Malaria is a deadly but neglected tropical disease that has received more money and attention in the last decade than in perhaps the preceding century. The disease is spread by mosquitoes in whose gut live one or more of five protozoan species of the Plasmodium genus. As a protozoa, it is neither a virus nor a bacteria but more like an amoeba or an algae, and thus it is more difficult to fight because its cells look more like human ones than either viruses or bacteria. Malaria is contracted by 350-500 million people every year, and approximately 1-3 million die of it annually - mostly sub-Saharan children. Now a scientist at the Johns Hopkins University Malaria Research Institute think he might have a unique way to help break the cycle of malarial infection.

The answer? Cure the mosquito.

For a long time it was thought that malaria could be controlled by using insecticides and bed screens to keep the mosquitoes away, but these approaches have both proven only partially effective. Insecticides also have their own toll on both human health and the environment, and rapidly become ineffective. But Dr. George Dimopoulos has found a species of bacteria living in the gut of the mosquito whose presence seems to inhibit the growth of the malaria protozoa. When he treated mosquitoes with an antibiotic, the bacteria died and the protozoa multiplied manyfold, making the mosquito a much deadlier vector for the disease. By helping this specific bacterium to stimulate the mosquito's immune system and cure it of the protozoans it carries, Dr. Dimopoulos believes, the spread of malaria could be controlled more effectively than with insecticides or bed screens alone.

If so, this could be a new and unprecedented breakthrough in fighting malaria, one of the great scourges of Africa.

For more information:
VOA News article

Public Library of Science article by Dr. Dimopoulos

Wikipedia entry on protozoa


© A Quantum of Science / Peter Smalley (2009)
Reproduction with attribution is appreciation