Doctor of Public Health

Assoc Prof Natasha Howard is a public health practitioner, educator, and interdisciplinary health policy and systems researcher with more than 25 years of global public health experience, spanning frontline practice, humanitarian response, policy research, and leadership. She has worked with and advised international organisations including WHO, UNFPA, UNDP, Population Services International, Médecins Sans Frontières, and Gavi, with substantial experience across Asia and Africa. Her early career included fieldwork in Jordan, Myanmar, and Afghanistan on tuberculosis, malaria, and maternal and newborn health, followed by humanitarian and technical roles including field epidemiology support during the 2014 Ebola response in Liberia.

Her research asks how public health systems can respond more effectively and equitably when resources are constrained, populations marginalised, and decisions politically or operationally complex. Drawing on social science, epidemiology, and health policy and systems research, she works across health-system governance, infectious disease control, conflict and displacement/migration, health equity, and governance. A consistent thread is translating evidence into policy and practice, understanding not simply what works, but how institutions, communities and decision-makers can operationalise this in real-world settings.

As Programme Director of the Doctor of Public Health, Prof Howard brings over 15 years of postgraduate teaching and programme leadership to the DrPH, alongside experience leading multidisciplinary research teams and mentoring public health professionals and researchers. She additionally coordinates SPH6903 Public Engagement and SPH6904 DrPH Dissertation and contributes to coordination of SPH6905 DrPH Portfolio. Her approach reflects the distinctive purpose of a DrPH, helping experienced professionals connect rigorous scholarship with leadership, policy and practice, and develop the judgement and skills needed to tackle complex public health problems and translate knowledge into meaningful change.

Assoc Prof Ng Yeuk Fan is a senior public health physician, health systems transformation leader, and educator whose work focuses on developing the leadership capabilities required to navigate increasingly complex health and healthcare systems. With more than two decades of experience spanning Singapore’s Ministry of Health, hospital, and regional health-system leadership, population health, integrated care, and organisational transformation, he brings to leadership development the perspective of both a practitioner and systems thinker. He also contributes internationally through advisory, teaching, and governance roles in health-system transformation and integrated care.

As Course Coordinator for SPH6901 Effective Public Health Leadership, Assoc Prof Ng’s approach extends beyond conventional individual leadership competencies to explore how leaders develop self-mastery, build high-performing teams, exercise strategic judgement, and steward complex systems characterised by interdependence, uncertainty, and distributed agency. His original work on Deep Systems Learning and Systemic Health Systems Leadership integrates systems thinking, organisational psychology, reflective practice, and practical transformation - helping leaders connect performance, experience, and learning while understanding relationships, power, purpose, and collective action. Increasingly, his work also explores human–AI complementarity and systems leadership in the age of AI, examining how leaders can harness emerging AI technologies while strengthening distinctly human capabilities of judgement, trust, sensemaking, and systemic stewardship.

Assoc Prof Piya Hanvoravongchai is a public health physician and health policy and systems expert whose career spans clinical practice, policy leadership, academic research and capacity building. His work focuses particularly on health financing, health equity and the development of stronger and more equitable health systems.

He has worked extensively at the interface of evidence, policy and implementation across Thailand and the wider Asia-Pacific region. He previously served as Secretary-General of the National Health Foundation in Thailand and has provided technical guidance to ministries of health, international development agencies and philanthropic organisations. His policy contributions have also included service on Thailand’s National Health Reform Commission and the Strategic Technical Advisory Committee of the Asia-Pacific Observatory on Health Systems and Policies.

As Course Coordinator for SPH6902 Evidence-Informed Public Health Policy and Decision-Making, Assoc Prof Piya draws on this combination of policy, research and practice experience to help DrPH students examine how evidence is interpreted, translated and used in real-world decision-making. Through the course, students develop the critical judgement needed to assess evidence, understand policy contexts and navigate the competing priorities and practical considerations that shape public health decisions.

Assoc Prof Matthias Paul Toh is a public health physician with extensive experience spanning primary care, chronic disease management, health services research, epidemiology and communicable disease control. His career has taken him across clinical, health-system and public health settings, with work encompassing disease surveillance, epidemiological analysis, health information systems and public health operations.

His practice included the development of health information and disease registry systems, as well as leadership in epidemiology and communicable disease surveillance. He currently heads the Epidemiology and Data Unit at the National Centre for Infectious Diseases. Beyond his operational roles, Assoc Prof Toh has contributed extensively to the development of the public health profession through the Preventive Medicine Residency Programme, specialist examinations, and professional leadership, including serving as President of the College of Public Health and Occupational Physicians in 2020-2022.

As joint Course Coordinator for SPH6905 Portfolio, Assoc Prof Toh brings this breadth of professional practice, public health leadership and practitioner development to the competency-based component of the DrPH. His experience in developing and assessing public health professionals complements the Portfolio’s emphasis on demonstrating competencies through applied practice and professional development.

Assoc Prof Chew Ling is a senior public health physician with extensive experience in health promotion, preventive health, public health strategy and programme development. At the Health Promotion Board (HPB), she has held leadership roles spanning research and strategic planning and currently serves as Group Director of Youth Preventive Service, overseeing public health services and programmes supporting the health and wellbeing of children and young people.

Her work extends beyond programme delivery to public health policy, capability development and international knowledge exchange. She heads HPB’s World Health Organization (WHO) Collaborating Centre for Health Promotion and Disease Prevention, which supports capacity building and the sharing of evidence-based approaches to health promotion across the region. She has also contributed to regional public health initiatives and to the development of public health practitioners in Singapore through the National Preventive Medicine Residency Programme.

As joint Course Coordinator for SPH6905 DrPH Portfolio, Assoc Prof Chew brings this combination of senior public health practice, programme leadership and practitioner development to the competency-based component of the DrPH. Her experience in translating public health evidence into programmes and practice, and in developing future public health professionals, complements the Portfolio’s emphasis on demonstrating competencies through applied work and professional practice.