COVID‑19 Science Advisory Council

Expert advice to guide university policy and practice

Established by the President, the COVID-19 Scientific Advisory Council brings together some of the region's leading infectious disease researchers from the Dalhousie Faculty of Medicine, helping ensure Dal's COVID-related decisions are informed by the latest scientific evidence and understanding of current variants including Omicron.

Its membership includes:

Jerry Aguinaga (co-chair), Executive Director, Environmental Health and Safety, Dalhousie University

Jerry Aguinaga is the Executive Director of Environmental Health and Safety (EH&S) at Dalhousie University.  He has a Bachelor of Technology (Environmental Studies) from CBU and Master of Science (Occupational Safety and Health) from Columbia Southern University and has worked in the Health and Safety sector for more than 30 years. Jerry has been leading the EH&S Office at Dalhousie since 2013 and has facilitated continuous improvement in EH&S management through engagement, consultation and collaboration with all members of the Dalhousie University community. Jerry has been integral in leading Dalhousie University’s COVID-19 response for the past two years and has been serving as an advisor to the provincial government in their pandemic response.

Lynn Johnston (co-chair), Professor, Division of Infectious Diseases, Department of Medicine

Dr. Lynn Johnston has extensive experience at the provincial and national levels in infection prevention and control and infectious diseases residency training, having chaired the Public Health Agency of Canada’s (PHAC) Steering Committee on Infection Control Guidelines and as a founding member of the Canadian Hospital Epidemiology Committee that, with PHAC, operates the Canadian Nosocomial Infection Surveillance Program (CNISP). She has chaired the Specialty Committee in Infectious Diseases, Royal College of Physicians and Surgeons of Canada. She is currently the physician advisor for Infection Prevention and Control for long-term care in Nova Scotia.

Dr. Johnston received her MD from Dalhousie University, followed by internship at the Royal Alexandra Hospital in Edmonton and internal medicine residency training at Dalhousie University. This was followed by infectious diseases (West Los Angeles Veterans Administration, University of California at Los Angeles) and hospital epidemiology (University of Virginia) fellowships and MSc (Epidemiology) from the University of Toronto.

Dr. Johnston’s research interests include the epidemiology of hospital-acquired infections, projects having included the prevalence of hospital-acquired infections in CNISP hospitals.

Lisa Barrett, Assistant Professor, Division of Infectious Diseases, Department of Medicine

Dr. Lisa Barrett is a clinician scientist with expertise in infectious disease and human immunology. She received her PhD (2008) and MD (2005) from Memorial University in Newfoundland. Her doctoral work investigated anti-viral responses to Hepatitis C virus in the context of HIV co-infection.

Dr. Barrett extended her medical training and completed an internal medicine residency at Dalhousie University in 2009 and an adult infectious disease fellowship at the University of Toronto in 2011. She completed postdoctoral and clinician scientist training at the National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, where she was the immunologic lead on several early phase clinical trials investigating direct-acting antiviral therapy for Hepatitis C virus and a Phase 1 trial of immune based therapy for Hepatitis B virus. She is currently leading research into the immunologic response to COVID-19, serving on national COVID-19 therapeutics advisory groups, and  overseeing COVID-19 therapeutics for Nova Scotians.

Gaynor Watson-Creed, Assistant Dean of Serving and Engaging Society

Dr. Gaynor Watson-Creed is a public health specialist physician with more than 16 years experience, having served as the former Medical Officer of Health for the Halifax area and Deputy Chief Medical Officer of Health for Nova Scotia, including during the first 18 months of the COVID-19 pandemic. She is the Assistant Dean of Serving and Engaging Society for Dalhousie University’s Faculty of Medicine, and an Assistant Professor in the Department of Community Health and Epidemiology.

Dr. Watson-Creed has an MD from Dalhousie University, an MSc from the University of Guelph, a BSc from the University of Prince Edward Island, and a Doctor of Science honoris causa from Acadia University. She also sits as chair or member of several national population health councils and boards, and is a passionate advocate for high-quality public health services in Canada.

Scott Halperin, Professor, Division of Infectious Diseases, Department of Pediatrics, Department of Microbiology and Immunology

Dr. Scott Halperin is a practising pediatric infectious disease specialist with an active research program that focuses on the diagnosis, treatment, and prevention of pertussis and other vaccine-preventable diseases. His research focuses on the diagnosis, treatment, and prevention of pertussis and other vaccine-preventable diseases.

As the Director of the Canadian Center for Vaccinology and Nominated Principal Investigator of the Canadian Immunization Research Network (CIRN), Dr. Halperin has played a foundational role in the establishment of these and other Canadian collaborative research networks undertaking evaluative vaccine research that informs public health policy and practice. His contributions to combatting COVID-19 include serving on the Nova Scotia Vaccine Expert Panel and the national COVID-19 Immunity Task Force Leadership Group and as Co-Chair of the Vaccine Surveillance Reference Group.

Dr. Halperin received his BSc from Stanford University and his MD from Cornell University.  He has a Fellowship in Pediatric Infectious Diseases from University of Virginia and University of Minnesota.

Todd Hatchette, Professor &Chief, Division of Microbiology and Immunology, Department of Pathology and Laboratory Medicine, Division of Infectious Diseases, Department of Medicine

Dr. Hatchette is the Chief of Service and Head for the Division of Microbiology, Department of Pathology and Laboratory Medicine in NSH Central Zone.  He is a Professor in the Department of Pathology with a cross-appointments in the Departments of Immunology and Microbiology and Medicine where he is a consultant Infectious Diseases.  In addition, Dr. Hatchette is the past President of the Association of Medical Microbiology and infectious Diseases (AMMI) Canada.

As a Medical Microbiologist and infectious Disease physician, Dr. Hatchette has expertise in the clinical and laboratory diagnosis of infections and has given CME lectures to various health care professional and serves as an advisor on a number of local, provincial and national committees. Under his leadership, the virology laboratory has studied the performance characteristics of COVID-19 diagnostics that has led to practice innovation and continues to be a leader in COVID-19 testing capacity in Canada.

Joanne Langley, Division Chief, Infectious Disease, Professor, Department of Pediatrics, Department of Community Health and Epidemiology

Dr. Joanne Langley is a Professor of Pediatrics (Division of Infectious Diseases) and Community Health and Epidemiology at Dalhousie University.  She currently serves as Associate Director (Clinical Evaluation Unit) of the Canadian Center for Vaccinology, is Head of the Division of Pediatric Infectious Diseases, and holds the Canadian Institutes of Health Research – GlaxoSmithKline Chair in Pediatric Vaccinology, Dalhousie University

Dr. Langley’s main research interests are in the epidemiology and prevention of respiratory infections, particularly Respiratory Syncytial Virus and influenza, and immunization decision making.


Dr. Langley’s work also focuses on vaccine policy and evidence-based decision making in immunization programs. She is a member of the Chief Science Advisor of Canada’s COVID-19 Science Expert Panel, chair of the COVID-19 Vaccine Task Force, and a former member of the Canadian Task Force on Preventive Health Care and Canada’s National Advisory Committee on Immunization (Chair, 2007-2011). She is an active investigator in the Canadian Immunization Research Network and leads its Clinical Trials Network (CTN).


Dr. Langley has a BA, Queen’s University at Kingston, her MD from Dalhousie University, and her MSc (Clinical Epidemiology) from McMaster University. She is also a Fellow with the Royal College of Physicians and Surgeons of Canada (Pediatrics, Infectious Diseases), University of Toronto

Christy Simpson, Head and Associate Professor, Department of Bioethics

Dr. Christy Simpson’s research focuses on ethics issues arising in health care, at the clinical, organizational, and systems levels. She collaborates on research which is “rethinking” rural health ethics as well as core concepts in organizational and paediatric ethics. She has been an advisor to the Nova Scotia Health Authority on several ethical issues arising out of the COVID-19 pandemic.

Dr. Simpson has a BA, BSc and an MA from McMaster, a PDF from University of Alberta and a PhD from Dalhousie.  She has also served as an Adjunct Professor, Australian Centre for Health Law Research, Faculty of Law, Queensland University of Technology and Past-President for the Canadian Bioethics Society.