Sir Gustav Nossal is famous for his contributions to the fields of antibody formation and immunological tolerance, and the former Chairman of the committee overseeing the World Health Organisation's Immunisation, Vaccines and Biologicals programme. This year, he's 89 years old. In this episode of The Leap Year, Gustav shares his insight on the global response to the coronavirus pandemic, the possibilities of science for good – and a window into his personal life during the long days of lockdown.