Professor Helen McShane talks about her work on a new vaccine against tuberculosis. There are about 9 million new cases and two million deaths every year from tuberculosis (TB). BCG, now over 100 years old, remains the only licensed vaccine against TB. It confers good protection against severe disease and meningitis, but doesn't protect against lung disease. After working on TB for 10 years, Professor Helen McShane developed MVA85A, a vaccine with the aim to boost the cellular immune response induced by BCG. Professor McShane explains why developing countries are especially in need of a new vaccine since HIV and TB epidemics overlap and show a devastating synergy.