For the first time in 20 years, locally transmitted cases of malaria have been reported across three US states. Scientists are trying to piece together why and how malaria is appearing in places where it's no longer endemic. Guest host Thomas Locke talks with Jane Carlton, the new director of the Johns Hopkins Malaria Research Institute, about her work decoding the genomes of the parasites that have infected individuals in Maryland to determine their lineage. They also discuss the role of climate change in malaria infections, the global fight against the disease, and the extent to which the public is at risk.