Plenary Speakers

Marcel Behr

Dr. Behr is Professor of Medicine at McGill University and Canada Research Chair in Mycobacterial Genomics.  He was the founding Director of the McGill International TB Centre which he led from 2012 to 2018.  He is the Associate Program Leader of the Infectious Diseases and Immunity in Global Health Program at the Research Institute of the McGill University Health Centre and co-Director of the McGill Interdisciplinary Initiative in Infection and Immunity (MI4). He is also Division Chief, McGill Infectious Diseases.


Dr. Behr trained at the University of Toronto, Queen’s, McGill and Stanford.  His work has been recognized by election into the Canadian Academy of Health Sciences, the Royal Society of Canada, the American Society for Clinical Investigation and the American Academy of Microbiology.  Dr. Behr’s lab uses bacterial genomic methodologies to study the epidemiology and pathogenesis of tuberculosis and other mycobacterial diseases.

Five learning points

The Tortoise and the Snail: Is Science on MAP and Crohn’s Moving Slowly or Very Slowly?

  1. Studies looking for an association between Mycobacterium avium paratuberculosis (MAP) and Crohn’s disease should use validated laboratory methodologies. 

  2. Labs using these methodologies to look for MAP in human samples should subject themselves to rigorous quality control, to ensure that their findings are robust.

  3. Clinical trials that monitor response to antibiotics do not formally address the MAP hypothesis; rather, they ask whether a defined treatment makes patients better. 

  4. Clinical trials that have embedded validated laboratory techniques can examine whether there is an association between MAP status and treatment response.

  5. Clinical trials that screen by MAP status and then randomize patients could provide evidence of a treatment benefit in MAP positive patients; to my knowledge, such trials have not been done.

Kumi De Silva

Dr Kumudika (Kumi) de Silva is an immunologist at the Sydney School of Veterinary Science at the University of Sydney and received her doctorate from the John Curtin School of Medical Research at the Australian National University. Her research career started with an interest in immune cell migration in response to oxidised lipids in atherosclerosis and subsequently in burn injury in humans, and now focuses on immune cell responses to infectious diseases in ruminants.

Dr de Silva’s research centres around cellular immune changes during infection with an emphasis on understanding nuances that enable some animals to avoid infection while others succumb to disease. Her work has identified biological markers that can be used to predict future disease outcome in ovine paratuberculosis as well as dysfunctional immunity in sheep that do not respond to vaccination. Current research projects include investigation of cellular immune responses that drive a healthy outcome for livestock as well as testing a vaccine prototype to determine its suitability for ruminants. Dr de Silva is Editor-in-Chief for the International Association for Paratuberculosis.

Dr de Silva is a strong advocate for equity and active inclusion. She co-founded, and is inaugural Chair, of the Mosaic Network at the University of Sydney which aims to empower and support staff from culturally and linguistically diverse backgrounds and to influence cultural change at the University and beyond. She is also a member of the University of Sydney’s Self-Assessment Team for the Science in Australia Gender Equity (SAGE) Athena SWAN pilot program for which the University recently received a Bronze award.

Five learning points

  1. Exposure to MAP can result in a spectrum of outcomes ranging from severe clinical disease to resilience to infection

  2. Early immune responses can be used to identify animals that have the potential to withstand disease progression

  3. Classification of disease outcome is important when assessing biomarkers for protective immunity

  4. A combination of cellular and molecular biomarkers is required to define resilience to paratuberculosis

  5. Immunological profiles of resilience could be used for diagnostics as well as for improving vaccine design

Frank Griffin

Frank Griffin (BA (Mod), PhD (dublin), ONZM, FRSNZ)

Frank graduated BA(Mod) (1967) and PhD TCD Vet School (1970). He is currently Emeritus Professor-in-Immunology at the University of Otago, which he joined as a lecturer in 1973.  Frank is Director of Disease Research Limited: a private diagnostic laboratory associated with the University of Otago. He is the author of more than 145 refereed and 60 non-refereed scientific publications. He has developed vaccines and laboratory assays to diagnose Yersiniosis, Tuberculosis (TB) and Paratuberculosis (Johne’s disease).Current research attempts to modulate infections to become Nature’s Vaccines. His awards include; NZ Deer Industry Award (1990); ONZM (2003); Pickering Medal (2010); FRSNZ (2012). 

Five learning points

  1. Complex diseases caused by mycobacterial pathogens will not be resolved by the application of singular simple remedies.

  2. The economic impacts of infectious diseases are cumulative and should incorporate the added management costs, combined with overall production losses.

  3. Effective control of chronic infectious disease in livestock demand co-incident  remediation strategies, supported fully by producers, scientists, veterinarians and regulators.

  4. For cost-effective control of chronic infectious disease in farm animal,  equal contributions are  made; through altered management (farmers), test performance (laboratories), epidemiology (veterinarians) and remedial interventions (regulators).

  5. Composite strategies for disease control are synergistic, where the sum of the parts are greater than the whole.

Marian Price Carter

Marian Price-Carter is a molecular biologist working as part of the TB diagnostic team at AgResearch Ltd. in Palmerston North New Zealand (NZ).  In collaboration with epidemiologists at OSPRI TBfree, a farmer driven organization formed to control bovine tuberculosis, this team detect and characterize Mycobacterium bovis and other mycobacterial infections in NZ livestock and wildlife.  Marian uses her graduate training in biophysical chemistry and her postdoctoral training in bacterial genetics to develop, establish and employ molecular methods that help to efficiently detect and type M. bovis and other mycobacteria, including routine use of whole genome sequencing to guide control efforts.

Five learning points

  1. Simple test and cull strategies that have led to eradication of bovine tuberculosis from livestock in other parts of the world are hampered in New Zealand (NZ) by reinfection from a wildlife reservoir.   

  2. OSPRI TBfree, a farmer driven organization, has greatly reduced M. bovis herd prevalence by taking an active, all-inclusive approach where they monitor and control infection both in livestock herds and wildlife, and regulate movement of stock. 

  3. Different types of M. bovis are regionally localized in NZ and for multiple decades strain typing has enhanced the efficiency of control by guiding OSPRI in the movement control of livestock, control within herds and enhanced wildlife control in the area of new herd infections. 

  4. The single nucleotide polymorphism (SNP) lineages that result from whole genome sequencing (WGS) analyses are proving to be far superior to previously employed typing assays for guiding control efforts.  

  5. Information from WGS about shared common ancestors has been helpful for clearly defining relationships and movement of NZ M. bovis, M. pinnipedii and MAP types.

Evan Sergeant

Evan is an epidemiologist and former Director of Ausvet, working as a consultant in Australia and internationally. He is a Member of the Australian College of Veterinary Scientists in Epidemiology and has a PhD on the epidemiology of paratuberculosis in sheep. Evan provided technical advice to Australia’s National Johne’s Control Program for many years, as well as undertaking numerous research projects on paratuberculosis in both sheep and cattle, particularly in relation to herd assurance and risk assessment.

Five learning points

Considerations for an effective national control programme for Johne’s disease in dairy herds

  1. National control of Johne’s disease is challenging due to the unique epidemiology of the disease and challenges in detection and stopping spread

  2. Regulatory programs tend to fail because of lack of producer support, insidious nature of the disease and the excessive cost imposed on producers by regulatory action

  3. Voluntary programs have mixed success but do have the potential to be more effective than regulatory programs

  4. Key components of a voluntary program should include: identification and targeting drivers of producer participation; farm-level risk assessment and management plans; herd-based assurance to identify low-risk animals for replacements; and farmer education and training

  5. Ongoing monitoring and evaluation of program performance is important, to determine whether the program is sustainable and is meeting the stated objectives.