The Next Big Thing #6: Disarming The Enemy
Posted by Richard Conniff on December 27, 2013
In 2010, mosquito-borne malaria made 210 million people sick. Of these, about 660,000 died, most of them small children in sub-Saharan Africa and South Asia. Dengue fever, another disease spread by mosquitoes, is almost as devastating. It afflicts up to 100 million people each year and now threatens to advance into the U.S. Standing in the path of both diseases is a Michigan State University microbiologist named Zhiyong Xi and a bacterium named Wolbachia. Wolbachia is present in about 28 percent of all mosquito species—but not the ones that transmit dengue or malaria. But Xi has figured out how to establish a heritable Wolbachia population in these species and has demonstrated that it prevents these mosquitoes from transmitting dengue fever or malaria.
For anyone who has been driven mad by mosquitoes, the old approach of killing as many as possible had obvious emotional appeal. But it was often environmentally disastrous, most notoriously with the broadcast application of the pesticide DDT. Xi believes the strategy of merely disarming mosquitoes could be safer while also giving public health officials a new tool to use in tandem with existing methods. Insecticide-treated bed netting, for instance, might still be the best protection from some night-biting mosquitoes. But Wolbachia could become the weapon of choice to neutralize the more challenging day-biters.