Positron emission tomography (PET) paired with the glucose metabolism probe, fluorodeoxyglucose (FDG), is considered ‘old’ technology in the field of cancer. A team found a new use for this ‘old’ technology in infectious diseases research. Using FDG-PET to image dengue infection in mice, the team has potentially uncovered a novel way to track the infection in real-time and more accurately assess the effectiveness of new dengue treatments.