The spectre of a devastating global pandemic has been raised more than once in recent years. Recent disease events such as SARS, H1N1, avian influenza and haemorrhagic fevers (Ebola, dengue, etc) have focussed attention as never before on the need to understand and prepare for these unpredictable events. A series of new infectious diseases have also emerged (many of them zoonoses, with their origins in animal species), linked to changing patterns of land use, interactions between humans, livestock and wildlife and new patterns of social behaviour. These new diseases threaten to reverse the progress made since 1945 towards improved global public health.

How can we work towards effective responses to the fast-changing and diverse conditions from which outbreaks and infectious diseases emerge or re-emerge, while also ensuring social justice for the most vulnerable?