Infectious diseases are the leading cause of death world-wide, accounting for a third of all deaths.
They are a significant and growing problem. Infection may also play a role in coronary artery disease, the commonest cause of death in England and Wales. The re-emergence of infectious diseases is a global as well as a UK problem. The PHLS contributes significantly to reducing the human, social and economic burden of ill-health by providing the evidence for public health interventions aimed at preventing or controlling communicable disease.