Epidemiologist and LSHTM Professor Emeritus John Patrick Vaughan passes away

John Patrick Vaughan, Professor Emeritus of Epidemiology and Public Health at the London School of Hygiene and Tropical Medicine (LSHTM), passed away on 26 July in London. He had been battling acute leukaemia and, more recently, a tumour. He was 87. A brilliant scientist and beloved teacher, Patrick mentored hundreds of health professionals across the world. I was privileged to be one of them. He supervised my doctoral work and played a pivotal role in shaping my career.

I first met Patrick in Dhaka in 1982. He was leading a short course on health systems evaluation at icddr,b, and I was asked to support the course by providing local case studies from my work at BRAC's Research and Evaluation Division. I did not know at the time that this encounter would be a turning point in my life. Patrick encouraged me to apply for the doctoral programme he was leading at LSHTM. I followed his advice and finally moved to London in October 1983. My thesis, which focused on evaluating BRAC's nationwide 'lobon-gur' (oral rehydration therapy or ORT) programme, used both qualitative and quantitative methods, now referred to as 'mixed methods', and was completed in a record two years and three months. This unexpectedly fast completion triggered a regulatory issue. The University of London at the time did not allow degrees to be awarded in less than three years. Patrick stepped in and wrote to the university to request an exception, which they granted. The thesis made a meaningful contribution to the field, introducing, among others, what came to be known as the "four diarrhoea theory."

Patrick's career in international health and health systems research was long and distinguished, with a focus on low- and middle-income countries. After earning his Diploma in Tropical Public Health in 1969 and his Doctorate in Medicine in 1978 from the University of London, he joined LSHTM in 1975. He headed the MRC Tropical Epidemiology Unit and established the Evaluation and Planning Centre (EPC) in 1979. Over the years, he worked with WHO in Geneva, the World Bank in Washington, and served as a public health consultant for the UK NHS. He also spent time in Papua New Guinea. In Tanzania, he helped establish a new medical school in Dar es Salaam. From 1995 to 1998, he served as research director at icddr,b in Bangladesh. He published prolifically and generously brought others along with him. I was fortunate to co-author many of those papers.

Even during the pandemic, Patrick remained intellectually active. He decided to revise one of his earlier books by incorporating lessons from COVID-19. True to form, he invited two of his former students to join the effort. With Patrick's leadership and the collaboration of Cesar Victora from the University of Pelotas in Brazil, the updated volume, Practical Epidemiology: Using Epidemiology to Support Primary Health Care, was published by Oxford University Press in 2021.

Patrick was a great friend of Bangladesh. During his visits and his time at icddr,b, he traveled extensively in the countryside. He often wondered aloud why poverty persisted in such a beautiful, fertile country. He believed deeply in BRAC's philosophy and visited its field programmes many times, always impressed by their innovation and impact. His wife, Pauline Macauley, his partner for over five decades, also contributed meaningfully to BRAC, particularly in its education programmes. In 2006, when BRAC registered in the UK as a charity, Patrick graciously agreed to serve as the inaugural chair of BRAC UK's Board of Trustees.
On a personal note, I owe much of my professional advancement to Patrick's guidance and support. He was a staunch believer in research publication. "Publish or perish," he used to say. In the mid-1990s, I shared with him a draft study on BRAC's tuberculosis programme. He was enthusiastic about both the methodology and findings and pushed me to submit the work to a high-impact journal. The result was our paper published in The Lancet.

Patrick may no longer be with us, but his influence lives on through his writings, his students, and the countless lives he touched. He is deeply missed. May his soul rest in peace.