Dr To graduated from the Chinese University of Hong Kong (CUHK), he currently is an Associate Consultant at Department of Medicine and Therapeutics, Prince of Wales Hospital, and Honorary Clinical Assistant Professor in the Stanley Ho Centre for Emerging Infectious Diseases, CUHK. Dr To is a respiratory specialist with special interest and training in sleep medicine. He is also the current president of the Hong Kong Society of Sleep Medicine. Yet he is also interested in other non-respiratory subjects like HIV medicine, influenza vaccination uptake and pulmonary TB. He has published a few papers on these topics, with the most recent paper on the new TB skin test with specific TB antigens.