Professor David Strachan is a distinguished epidemiologist renowned for his groundbreaking contributions to understanding the epidemiology of chronic diseases. He currently holds an emeritus chair in epidemiology at St George's, University of London, following his retirement in April 2022 after a distinguished career spanning more than three decades. Having received his undergraduate education at Cambridge and Edinburgh universities, he completed vocational training in general practice before embarking on his epidemiological research journey. Throughout his tenure at St George's, where he joined as a senior lecturer in 1990, he led the development of community health later renamed population health serving as head of department research centre or research institute from 2004 to 2016.
Professor Strachan's most influential scholarly contribution is the seminal 1989 paper proposing what became widely known as the hygiene hypothesis for allergic disease a conceptual framework that has fundamentally reshaped scientific understanding of allergy development. This pioneering work which has been cited more than 2800 times posited that reduced exposure to infectious agents in early childhood due to improved hygiene and smaller family sizes contributes to increased susceptibility to allergic diseases. His systematic reviews of the effects of parental smoking on children's health conducted jointly with Professor Derek Cook formed a critical evidence base that influenced legislative changes banning smoking in cars with children present across multiple countries. His extensive research portfolio encompasses allergic respiratory and cardiovascular conditions establishing him as a leading authority in population health epidemiology.
Professor Strachan made significant contributions to academic instruction through undergraduate teaching in public health and postgraduate teaching in evidence based practice at St George's University of London. His enduring impact on public health policy and medical understanding continues through the widespread adoption of the hygiene hypothesis which has generated decades of subsequent research and clinical applications worldwide. In 1999 he was awarded the European Respiratory Society prize for paediatric respiratory research in Europe recognizing his exceptional contributions to the field. Following his retirement he was honored with an honorary fellowship from St George's in July 2022 reflecting his lasting legacy as one of the most influential epidemiologists of his generation whose work continues to guide research and public health interventions globally.
