Professor Emeritus

Andrew Simor

Department of Laboratory Medicine & Pathobiology - Medical Microbiology


Sunnybrook Health Science Centre
2075 Bayview Ave., Microbiology, Room B103, Toronto, Ontario Canada M4N 3M5
Appointment Status

Dr Simor graduated with a medical degree from the University of Toronto in 1976, and completed Royal College fellowship training in internal medicine, infectious diseases, and medical microbiology. 

He has worked at Sunnybrook Health Sciences Centre since 1993. 

Dr Simor is recognized nationally and internationally as a leader in the field of hospital epidemiology. 

He has received research funding from peer-reviewed and industry-based granting agencies. 

He has published a large number of papers in scientific journals, and he is on the Editorial Board of the journal, Infection Control and Hospital Epidemiology, and is an Associate Editor for the Canadian Journal of Infectious Diseases and Medical Microbiology. 

His primary research interests include: 

  • antimicrobial resistance
  • hospital-acquired infections
  • the application of molecular technologies to the diagnosis and management of infectious diseases. 

Dr Simor has received several teaching award from the university, and in 2005 was selected to receive the Distinguished Service Award from the university’s Department of Laboratory Medicine & Pathobiology. 

He has also received a Canadian Hospital Infection Control Association Award of Merit for service in the advancement of infection prevention and control. 


Research Synopsis


The organism of primary concern is methicillin-resistant Staphylococcus aureus (MRSA), but I am also interested in vancomycin-resistant enterococci (VRE), multidrug-resistant gram-negative bacilli, and Clostridium difficile.

My research is primarily clinical and epidemiological in understanding the epidemiology, risks, and outcomes associated with important healthcare-associated infections, and infections caused by antibiotic-resistant organisms such as methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile. 

As such, I am a lead investigator in a network of Canadian hospitals known as the Canadian Nosocomial Infection Surveillance Program (CNISP), which has been conducting prospective surveillance for a variety of important healthcare-related infections since 1995. 

My laboratory-based investigations involve studies of mechanisms of resistance to antimicrobial agents, as well as evaluations of methods used to improve the detection of antibiotic resistance. 

I am also interested in the application of molecular technology (nucleic acid amplification test methods and molecular typing) to the diagnosis, management, and prevention of infectious diseases.


Recent Publications


Stamper PD, Louie L, Wong, H, Simor AE, Farley JE, Carroll KC. Genotypic and phenotypic characterization of methicillin-susceptible Staphylococcus aureus isolates misidentified as methicillin-resistant Staphylococcus aureus by the BD GeneOhm MRSA assay. J Clin Microbiol 2011; 49: 1240-4. 

Wilkinson K, Gravel D, Taylor G, McGeer A, Simor AE, Suk K, Moore D, Kelly S, Boyd D, Mulvey M, Miller M. Infection prevention and control practices related to Clostridium difficile infection within Canadian acute and long-term care institutions. Am J Infect Control 2011; 39: 177-82.

Palmay L, Walker SAN, Walker SE, Simor AE.  Symptom reporting compared with audiometry for the detection of cochleotoxicity in patients on long-term aminoglycoside therapy. Ann Pharmacother 2011; 45:590-5.

Kaki R, Elligsen M, Walker S, Simor AE, Palmay L, Daneman N. Impact of antimicrobial stewardship in critical care: a systematic review. J. Antimicrob Chemother 2011; 66: 1223-30.

Tsuji BT, MacLean RD, Dresser LD, McGavin MJ, Simor AE.  Impact of accessory gene regulator (agr) dysfunction on vancomycin pharmacodynamics among Canadian community and health-care associated methicillin-resistant Staphylococcus aureus. Ann Clin Microbiol Antimicrob 2011; 10:20-5.

Broukhanski G, Simor AE, Pillai DR. Defining criteria to interpret multilocus variable-number tandem repeat analysis and Clostridium difficile outbreak investigation. J Med Microbiol 2011; 60: 1095-100.

Longtin J, Seah C, Siebert K, McGeer A, Simor AE, Longtin Y, Low DE, Melano RG. Distribution of antiseptic resistance genes qacA, qacB, and smr in methicillin-resistant Staphylococcus aureus isolated in Toronto, Canada, from 2005 to 2009. Antimicrob Agents Chemother 2011; 55:2999-3001.

Williams VR, Callery S, Vearncombe M, Simor AE.  Universal versus targeted active surveillance for methicillin-resistant Staphylococcus aureus in medical patients. Can J Infect Control 2011; 26:105-11.

Amiali NM, Golding GR, Sedman J, Simor AE, Ismail AA.  Rapid identification of community-associated methicillin-resistant Staphylococcus aureus by Fourier transform infrared spectroscopy. Diagn Microbiol Infect Dis 2011; 70:157-66.

McElhaney JE, Simor AE, McNeil S, Predy GN, Efficacy and safety of CVT-E002, a proprietary extract of Panax quinquefolius in the prevention of respiratory infections in influenza-vaccinated community-dwelling adults: a multicenter, randomized, double-blind, and placebo-controlled trial. Influenza Research and Treatment 2011;doi: 10.1155/2011/759051.

Kus JV, Tadros M, Simor AE, Low DE, McGeer AJ, Willey BM, Mulvey MR, Louie L, Richardson D, Carr L, Jinnah F, Poutanen SM. New Delhi metallo-ß-lactamase-1: local acquisition in Ontario, Canada, and challenges in detection. Can Med Assoc J 2011; 183:1257-61.

Kuster SP, Katz KC, Blair J, Downey J, Drews S, Fowler R, Green K, Gubbay J, Mazzulli T, Powis J, Sarabia A, Simor AE, McGeer A. When should a diagnosis of influenza be considered in adults requiring intensive care unit admission?  Results of population-based active surveillance in Toronto. Critical Care 2011; 15:R182.

Simor AE. Staphylococcal decolonization: an effective strategy for prevention of infection? Lancet Infect Dis 2011; 11:952-62.

Thistle P, Bolotin S, Lam E, Schwarz D, Pilon R, Ndwana B, Simor AE, Silverman M. Highly active anti-retroviral therapy in the prevention of mother-to-child transmission of HIV in rural Zimbabwe during the socio-economic crisis.  Medicine, Conflict, and Survival 2011; 27: 165-76.

Elligsen M, Walker SAN, Simor AE, Daneman N.  Prospective audit and feedback of antimicrobial stewardship in critical care: program implementation, experience, and challenges. CJ Hosp Pharm 2012; 65: 31-6.

Quach C, McArthur M, McGeer A, Li L, Simor AE, Dionne M, Lévesque E, Tremblay L.  Risk of infection following a visit to the emergency department:  a cohort study. Can Med Assoc J 2012; 184: E232-9. (DOI: 10.1503/cmaj.110372)

Elligsen M, Walker SAN, Pinto R, Simor AE, Mubareka S, Rachlis A, Allen V, Daneman N.  Audit and feedback to reduce broad-spectrum antibiotic use among intensive care unit patients: a controlled interrupted time series analysis. Infect Control Hosp Epidemiol 2012; 33: 354-61.

Seah C, Alexander DC, Louie L, Simor AE, Low DE, Longtin J, Melano RG. MupB, a new high-level mupirocin resistance mechanism in Staphylococcus aureus. Antimicrob Agent Chemother 2012; 56:1916-20.

Elligsen M, Walker SAN, Walker SE, LePiane F, Lathia N, De’Angelis C, Simor AE.  Comparison of mortality between nosocomial and community-acquired febrile neutropenia patients treated initially with cefazolin plus tobramycin:  retrospective chart review. Eur J Clin Microbiol Infect Dis 2012; 31: 1141-50.

Mataseje LF, Bryce E, Roscoe D, Boyd DA, Gravel D, Katz K, Kibsey P, Mounchili A, Simor AE, Taylor G, Mulvey MR.  Carbapenem-resistant Gram-negative bacilli in Canada 2009-10: results from the Canadian Nosocomial Infection Surveillance Program (CNISP). J Antimicrob Chemother 2012; 67: 1359-67.



Chief, Department of Microbiology, Sunnybrook Health Sciences Centre
Chief, Division of Infectious Diseases, Sunnybrook Health Sciences Centre
Senior Scientist, Sunnybrook Research Institute


Honours and Awards

Name: Canadian Hospital Infection Control Association Award of Merit