Shiranee is Professor of Infectious Diseases at Imperial College London and a Clinical Infectious Diseases consultant at Hammersmith and St Mary’s Hospitals. She leads the Gram Positive Pathogenesis research group within the Department of Infectious Disease, and is clinical director of Imperial’s Centre for Bacteriology Resistance Biology. Her group works on the mechanisms that allow Streptococcus pyogenes to cause extreme clinical phenotypes in individuals and populations. Transmission is a new research area, sparked by a recognition of the intensity of spread that can occur.