Professor Cowling joined the School of Public Health at HKU in 2004. Prior to moving to Hong Kong, he graduated with a PhD in medical statistics at the University of Warwick (UK) in 2003, and spent a year as a postdoc at Imperial College London (UK). He has been the Head of the Division of Epidemiology and Biostatistics since 2013, where he is responsible for teaching introductory modules in epidemiology and biostatistics on the MPH curriculum, and his primary research focus is in infectious disease epidemiology. Cowling is a member of the WHO Collaborating Centre for Infectious Disease Epidemiology and Control at HKU SPH.

In recent years, Cowling has designed and implemented large field studies of influenza transmission in the community and the effectiveness and impact of control measures. His research aims to integrate information on transmission dynamics at the individual level with disease burden, severity and dynamics at the population level. His latest research has focused on the modes of respiratory virus transmission, influenza vaccine effectiveness, and the potential causes and implications of interference between respiratory viruses. He has strong links with the China CDC, and the NIGMS-funded Harvard Center for Communicable Disease Dynamics.

Cowling is a fellow of the Royal Statistical Society and a member of the American Statistical Association. He is a Section Editor of the journal PLOS ONE, a Senior Editor of the journal Influenza and Other Respiratory Viruses, and a founding editor of the journal PLOS Currents: Outbreaks.