Facebook Pixel Code
About Sickkids
About SickKids

Valerie Waters, MD, MSc

The Hospital for Sick Children
Staff Physician
Infectious Diseases

Research Institute
Senior Associate Scientist
Translational Medicine

University of Toronto
Associate Professor
Department of Paediatrics

Chair Positions

Cystic Fibrosis Canada
Healthcare Advisory Council

Phone: 416-813-7654 ext. 204541
Fax: 416-813-8404
Email: valerie.waters@sickkids.ca

Brief Biography

Dr. Valerie Waters is an Associate Professor of Paediatrics at the University of Toronto and has been a full-time staff physician in the Division of Infectious Diseases at The Hospital for Sick Children (SickKids) in Toronto since 2005. She is also a Senior Associate Scientist in Translational Medicine at the SickKids Research Institute. Dr. Waters received her MD from McGill University, Montreal, Canada and did her paediatric residency at SickKids. She then completed a paediatric infectious diseases fellowship at Columbia Presbyterian Medical Centre and obtained her Masters in Biostatistics at Columbia University, New York.

Academic Background

M.Sc. Biostatistics, Columbia University School of Public Health (2003-2005)

M.D., McGill University (1993-1998)

B.Sc., Marianopolis College, Diploma of Collegial Studies in Health Sciences (1991-1993)

Research Interests

My research program is focused on the investigation of the epidemiology and treatment of multi-drug resistant bacterial pathogens causing lung infections in patients with cystic fibrosis (CF). I am particularly interested in the way these organisms grow as communities of bacteria known as biofilms, which are associated with increased antimicrobial resistance. My lab has developed novel biofilms models to test the efficacy of compounds against Pseudomonas aeruginosa biofilms, in the context of host factors and other microbes. We are currently studying the interaction between Staphylococcus aureus and P. aeruginosa grown within biofilms in the context of failure of early eradication treatment of P. aeruginosa in children with CF. In addition, we also investigate the effects of antibiotic treatment of pulmonary exacerbations in CF and are conducting a clinical trial of oral prednisone as an adjuvant therapy in CF patients with pulmonary exacerbations.  

External Funding

  • US Cystic Fibrosis Foundation
  • Cystic Fibrosis Canada
  • Canadian Institute for Health Research


  • Nominee-Subspecialty Education Award, Hospital for Sick Children (2007)
  • POR Scholar, Joseph L. Mailman School of Public Health, Academic Scholarship, Columbia University (2005)
  • Frederick Fitzgerald Tisdall Award for Research (1999)


  1. Parkins M, Somayaji R, Waters V. Epidemiology, Biology and Impact of Clonal Pseudomonas aeruginosa Infections in Cystic Fibrosis. Clin Micro Rev. 2018 Jun. In Press. SRA
  2. Waters V. Chronic antibiotic use in cystic fibrosis: a fine balance. Ann Am Thorac Soc. 2018 Jun;15(6):667-668. PA
  3. Middleton M, Layeghifard M, Klingel M, Stanojevic S, Yau Y, Zlosnik JEA, Coriati A, Ratjen FA, Tullis DE, Stephenson A, Wilcox P, Freitag A, Chilvers M, McKinney M, Lavoie A, Wang PW, Guttman DS, Waters VJ. Epidemiology of clonal Pseudomonas aeruginosa infection in a Canadian cystic fibrosis population. Ann Am Thorac Soc. March 2018. In Press. SRA
  4. Waters V, Grimwood K. Defining chronic Pseudomonas aeruginosa infection in cystic fibrosis. J Cyst Fibros. 2018 May;17(3):292-293.  PA
  5. Blanchard AC, Rooney AM, Yau YCW, Zhang Y, Stapleton PJ, Horton E, Klingel M, Stanojevic S, Ratjen F, Coburn B, Waters V. Early detection using qPCR of Pseudomonas aeruginosa infection in children with cystic fibrosis undergoing eradication treatment. J Cyst Fibros. 2018 Mar 7. pii: S1569-1993(18)30031-6. SRA
  6. Beaudoin T, Yau YCW, Stapleton PJ, Gong, Y, Wang PW, Guttman DS, Waters V. Staphylococcus aureus interaction with Pseudomonas aeruginosa biofilm enhances tobramycin resistance. NPJ Biofilms and Microbiomes 2017 Oct 19;3:25. SRA
  7. Waters V, Ratjen F. Standard versus biofilm antimicrobial susceptibility testing to guide antibiotic therapy in cystic fibrosis. Cochrane Database Syst Rev. 2017 Oct 5;10:CD009528. doi: 10.1002/14651858.CD009528.pub4. PA
  8. Singh M, Wang S, Yau Y, Waters V, Kumar A. MexXY efflux pump overexpression and aminoglycoside resistance in cystic fibrosis isolates of Pseudomonas aeruginosa from chronic infections. Can J Microbiol. 2017 Dec;63(12):929-938. C
  9. Jessamine P, Stephenson A, Brode S, Alvarez G, Weese S, Lechner J, Waters V, Fulford M, Filijski C, Sider D, Kim J, Jamieson F, Marras T. Provincial Infectious Diseases Advisory Committee on Communicable Diseases (PIDAC-CD). Best practices for pulmonary nontuberculous mycobacteria. Toronto, ON: Queen's Printer for Ontario; 2017. Supported by the Ontario Agency for Health Protection and Promotion (Public Health Ontario). C
  10. Waters V, Ratjen F. Combination antimicrobial susceptibility testing for acute exacerbations in chronic infection of Pseudomonas aeruginosa in cystic fibrosis. Cochrane Database Syst Rev. 2017 Jun 19;6:CD006961. doi: 10. PA
  11. Kordy F, Waters V, Den-Hollander C, Lam R, Stephens D, Kitai I. Optimizing blood collection and processing for QuantiFERON-TB Gold-In Tube testing gives low rates of indeterminate results: clinical implications. Pediatr Infect Dis J. 2017 Aug; 37(1): e22-e24. C
  12. Somayaji R, Stanojevic S, Tullis E, Stephenson A, Ratjen F, Waters V. Clinical outcomes associated with Achromobacter species infection in patients with cystic fibrosis.  Ann Am Thorac Soc. Ann Am Thorac Soc. 2017 Sep;14(9):1412-1418. SRA
  13. Waters V, Yau Y, Beaudoin T, Wettlaufer J, Tom SK, McDonald N, Rizvi L, Klingel M, Ratjen F, Tullis E. Pilot trial of tobramycin inhalation powder in cystic fibrosis patients with chronic Burkholderia cepacia complex infection. J Cyst Fibros. 2017 Jul;16(4):492-495. PA