A Conversation with Kumudini Meepagala

T he spread of the Zika virus is raising fears that the virus’s most heartbreaking consequencebabies with microcephaly born to infected motherswill affect the U.S. and other countries as it has affected Brazil. The virus hitches a ride with Aedes aegypti mosquitoes, whose preference for biting humans makes them an ideal vector for transferring virus from one victim to another. Repellents are the first line of defense against mosquito bites, but some studies suggest that the most popular repellent, DEET, damages the central nervous system of insects such as honeybees, as well as mammals. Searching for mosquito repellents without worrying side effects, Kumudini Meepagala, a natural products chemist with the U.S. Department of Agriculture in Mississippi, recently isolated and modified a plant compound that works better than DEET. She spoke to Janet Pelley about how she pulled the natural repellent out of Texas torchwood (Amyris texana), a shrub in the citrus family.