Biosecurity

A Bizarre Bacteria Could Be the Key to Controlling Mosquitoes

IN FEBRUARY OF 1967, German biologist Hannes Laven hiked to a village 16 miles north of Yangon, Myanmar. He carried with him 100 mosquitoes from Fresno, California—50 males that had been infected with a bacteria called Wolbachia, and 50 females that had not. He bred these mosquitoes together, separated out the males from the thousands of offspring, and released them around the town’s 150 thatched-roof houses. Twelve weeks and six generations of California-Myanmar cross-breeding later he had eradicated the entire local mosquito population: None of their eggs would hatch.

For 50 years, scientists have known that Wolbachia can cause sterility in mosquitoes and other insects. But now, for the first time, they finally understand exactly how it works.