This spring, a U.K.-based company released genetically engineered mosquitos in the Florida Keys – part of an experiment that researchers hope could eventually result in a new weapon against diseases like Dengue Fever. Mosquitos have long been associated with the spread of vector-borne diseases, but scientists hope by genetically altering their DNA, they could prevent them from passing on pathogens to humans. A similar experiment was carried out two years ago in Burkina Faso, where Malaria is endemic. But for some, the practice has raised questions about the impact on local ecosystems and potentially on human health. Alyssa Julie explains.