Email nancy.leung@nus.edu.sg

Dr. Nancy Leung is an infectious disease epidemiologist with over 10 years of experience conducting internationally collaborative research on the epidemiology of influenza, SARS-CoV-2 and other respiratory viruses. She had diverse research training in immunology, virology (MPhil), and epidemiology (PhD). She has served as Principal Investigator for community-based longitudinal observational cohorts, randomised vaccine trials, and household transmission studies involving over 4,000 participants in Hong Kong and mainland China, generating empirical data on individual and population immunity, vaccine response, transmission, and disease burden. She is also interested in causal inference analyses. Dr. Leung has received funding support from the Hong Kong HMRF, US NIH and China NFSC.

Dr. Leung was featured as one of the “Five science stars making their mark in China” by Nature Index for providing early evidence on coronavirus airborne transmission and facemask effectiveness. She was Co-Chair/Member for two WHO advisory groups on SARS-CoV-2 indoor airborne risk assessment (ARIA) and standardizing terminology for pathogen transmission through the air (TTAT). She currently serves as an Editor for the International Journal of Epidemiology (IJE), and a Council member of the International Society for Respiratory Viruses (ISRV).

Dr. Leung has taught an introductory epidemiology course at the graduate level (class size 200+), led problem-based learning (PBL) for medical students, and supervised research postgraduates.

• NUS Saw Swee Hock School of Public Health
• WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, The University of Hong Kong

• Epidemiology
• Respiratory viruses, including COVID-19 and influenza
• Vaccination
• Individual and population immunity
• Transmission

• Epidemiologic study designs
• Respiratory virus infections
• Emerging infectious diseases
• Vaccines
• Clinical research methods

• BSc (Biochemistry; German), The University of Hong Kong.
• MPhil (Microbiology), The University of Hong Kong.
• PhD (Public Health), The University of Hong Kong.

• Sino-British Fellowship Trust Visitorship, Sino-British Fellowship Trust, United Kingdom. 2016 (as Visiting Research Fellow at the Farr Institute of Health Informatics Research, University College London)
• Best Abstract in the category ‘Infection Control’, 17th Asia-Pacific Congress of Clinical Microbiology and Infection cum 8th International Infection Control Conference. 2018
• Best Poster Award in the category ‘Public Health’, Options for the Control of Influenza X. 2019
• Faculty Outstanding Research Output Award, LKS Faculty of Medicine, The University of Hong Kong. 2021
• Research Fellowship Scheme, Health and Medical Research Fund (HMRF), Hong Kong. 2021
• One of the Five Science Stars making their mark in China, Nature Index. 2021
• Takemi Program in International Health, Harvard T. H. Chan School of Public Health, United States. 2022 (as Visiting Scholar at the Department of Global Health and Population, and CAUSALab/ Center for Communicable Disease Dynamics, Department of Epidemiology)

• Post-doctoral research associate (Honorary), The Farr Institute of Health Informatics Research, University College London, London, United Kingdom. 2016-18
• Post-doctoral fellow, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong (HKUMed), Hong Kong. 2017-19
• Research Assistant Professor, School of Public Health, HKUMed, Hong Kong. 2020-21
• Takemi Fellow, Harvard T. H. Chan School of Public Health, Boston, MA, United States. 2022-23
• Assistant Professor, World Health Organization Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, HKUMed, Hong Kong. 2023-26

• Member, Scientific Program Committee, Joint Conference of the International Society for Clinical Biostatistics (ISCB) and the German Association for Medical Informatics, Biometry and Epidemiology (GMDS) 2026, Freiburg, Germany. 2025-
• Takemi Ambassador, Takemi Program in International Health, Harvard T. H. Chan School of Public Health, United States. 2025-
• Council Member, International Society for Respiratory Viruses (ISRV). 2024-
• Editor, International Journal of Epidemiology (IJE). 2023-
• Reviewer, WHO public health and social measures (PHSM) master protocol 01: Air quality improvement interventions in schools to reduce respiratory infections: a cluster-randomized trial. 2026
• Member, Selection Committee, Innovation and Technology Scholarship, The University of Hong Kong. 2026
• Member, Scientific Committee, OPTIONS for the Control of Influenza XI, ISRV, Belfast, UK. 2022
• Member, WHO Technical Advisory Group on Through-the-air-transmission (TTAT). 2022-24
• Co-Chair, WHO Technical Advisory Group on Airborne Risk Indoor Assessment (ARIA). 2021-2

• Xie Y, Shiu EYC, Ye D, Zhang W, Huang W, Yang Z, Cowling BJ, Leung NHL^. Detection of airborne respiratory viruses in paediatric patient rooms in Guangzhou, China. Journal of Hospital Infection 2026; 173:21-9.
• Cheng SM*, Leung NH*, Shiu EY, Wong RW, Au NY, Huang X, Kwok NK, Chan CH, Li JK, Tsang LC, Kwan TC, Tsang TK, Poon LL, Cowling BJ, Peiris M. Population immunity, post-vaccine and post-infection antibody responses to influenza A (H3N2) subclade J.2 and K (J.2.4.1) viruses, Hong Kong, 2025. Eurosurveillance 2026; 31.
• Li X, Cheng SMS, Chen Y, Ho F, Liu G, Au A, Yu N, Ip DKM, Peiris M^, Cowling BJ^, Leung NHL^†. Diagnostic performance of self-collected respiratory swabs for SARS-CoV-2 and influenza virus in community-dwelling older adults. Influenza and Other Respiratory Viruses 2026; 20:e70241.
• Fox A, Sánchez-Ovando S, Carolan L, Hadiprodjo AJ, Chen Y, Ho F, Cheng SMS, Thompson MG, Iuliano AD, Levine MZ, Valkenburg SA, Ip DKM, Peiris JSM, Sullivan SG, Cowling BJ^, Leung NHL^. Enhanced influenza vaccines extend A(H3N2) antibody reactivity in older adults but prior vaccination effects persist. Clinical Infectious Diseases 2025; 81(4):e192-e201.
• Leung NHL*†, Milton DK. New WHO proposed terminology for respiratory pathogen transmission. Nature Reviews Microbiology, 2024; 22:453-4.
• Cohen CA*, Leung NHL*, Kaewpreedee P, Lee KWK, Jia JZ, Cheung AWL, Cheng SMS, Mori M, Ip DKM, Poon LLM, Peiris JSM, Cowling BJ, Valkenburg SA. Antibody Fc receptor binding and T cell responses to homologous and heterologous immunization with inactivated or mRNA vaccines against SARS-CoV-2. Nature Communications, 2024; 15:7358.
• Leung NHL*, Cheng SMS*, Cohen CA*, Martin-Sanchez M, Au NYM, Luk LLH, Tsang LCH, Kwan KKH, Chaothai S, Fung LWC, Cheung AWL, Chan KCK, Li JKC, Ng YY, Kaewpreedee P, Jia JZ, Ip DKM, Poon LLM, Leung GM, Peiris JSM, Valkenburg SA, Cowling BJ. Comparative antibody and cell-mediated immune responses, reactogenicity, and efficacy of homologous and heterologous boosting with CoronaVac and BNT162b2 (Cobovax): an open-label, randomised trial. Lancet Microbe, 2023; 4:e670-e82.
• Cowling BJ, Cheng SMS, Martín-Sánchez M, Au NYM, Chan KCK, Li JKC, Fung LWC, Luk LLH, Tsang LCH, Ip DKM, Poon LLM, Leung GM, Peiris JSM^, Leung NHL^. Slow waning of antibodies following a third dose of BNT162b2 in adults who had previously received two doses of inactivated vaccine. Journal of Infectious Diseases 2023; 227:251-5.
• Leung NHL*. Transmissibility and transmission of respiratory viruses. Nature Reviews Microbiology, 2021; 19:528-45. (Highly Cited Paper)
• Leung NHL*, Chu DKW, Shiu EYC, Chan KH, McDevitt JJ, Hau BJP, Yen HL, Li Y, Ip DKM, Peiris JSM, Seto WH, Leung GM, Milton DK, Cowling BJ. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nature Medicine, 2020; 26(5):676-80. (Highly Cited Paper)
• Lim WW, Leung NHL†, Sullivan SG, Tchetgen Tchetgen EJ, Cowling BJ†. Distinguishing causation from correlation in the use of correlates of protection to evaluate and develop influenza vaccines. American Journal of Epidemiology, 2020; 189(3): 185-92.
• Leung NH*, Zhou J, Chu DK, Yu H, Lindsley WG, Beezhold DH, Yen HL, Li Y, Seto WH, Peiris JS, Cowling BJ. Quantification of influenza virus RNA in aerosols in patient rooms. PLoS One 2016; 11(2): e0148669.
• Leung NH*, Xu C, Ip DK, Cowling BJ. The fraction of influenza virus infections that are asymptomatic: a systematic review and meta-analysis. Epidemiology, 2015; 26(6): 862-72.
• Yip MS*, Leung NH*, Cheung CY, Li PH, Lee HH, Daeron M, Peiris JS, Bruzzone R, Jaume M. Antibody-dependent infection of human macrophages by severe acute respiratory syndrome coronavirus. Virology Journal, 2014; 11(1): 82.