Preventing AMR in hospitals: Q&A with infectious disease expert Dominik Mertz

BY MICHAEL CORDEIRO

OCTOBER 18, 2022

Dominik Mertz, director of the division of Infectious Diseases in the department of Medicine at McMaster, is the newly named holder of the Michael G. DeGroote Chair in Infectious Diseases.

The chair, established in 2010 through a gift from DeGroote, is awarded to highly accomplished researchers who contribute significantly to the body of scholarship around infectious diseases through teaching and research.

Mertz was born in Switzerland and trained there as an infectious diseases physician, earning his medical degree in 2002. He came to Canada in 2009 to pursue a master’s degree in health research methodology at McMaster and joined the university as a faculty member in 2011.

As an infectious disease internist, Mertz played a critical role in Hamilton Health Sciences’ pandemic response, providing guidance on matters related to personal protective equipment (PPE) management, masking and vaccination, outbreak management, and patient and staff concerns.

A researcher, educator and clinician, Mertz is affiliated with several units across the university, including the Michael G. DeGroote Institute for Infectious Disease Research (IIDR); Canada’s Global Nexus for Pandemics and Biological Threats; the department of Health Research Methods, Evidence and Impact (HEI); the department of Pathology and Molecular Medicine; and the Population Health Research Institute (PHRI).

We sat down with Mertz to learn more about his role, his work and how he is supporting McMaster’s fight against pandemics. 

What is an infectious disease?

An infectious disease is any type of disease or illness caused by an infectious pathogen — typically bacteria, virus or parasite.

Some of the most common diseases we see include surgical-site infections (SSI), respiratory infections (both bacterial and viral), skin or soft tissue infections, and infections that attack the feet of patients with diabetes.

One of your research interests focuses on the antimicrobial resistance (AMR) pandemic — a growing crisis caused by drug-resistant bacteria, viruses, parasites and fungi. What steps can we take to reduce AMR in clinical settings?

It begins with the right diagnosis. We are treating far too many viral infections as possible bacterial infections, like pneumonia, and exposing patients to unnecessary antibiotics. Unfortunately, there’s a gap in our current diagnostics and we urgently need to find better ways to identify the causes of infections.

Another step is shortening the duration of antibiotics. Historically, patients are prescribed antibiotics and advised to take their medicine for an arbitrary length of time, like 10 to 14 days. You’re also told to complete the entire course of medicine or your infection will become resistant to the medication. But the key to reducing resistance is to shorten the duration of treatment.

Data from trials suggest we can go down to as short as five-day courses. I’ve been working to translate these findings into clinical practice and sharing the evidence with physicians to nudge them in this new direction.

The last big piece is narrowing the spectrum of antibiotics. This involves reducing the public use of broad-spectrum and “strong” antibiotics. For more common infections, we can go back to using basic antibiotics like penicillin, which will prevent antimicrobial resistance to more advanced medicines.

What is your role as the chair holder?

Funding from the chair allows dedicated time for research, as well as the ability to develop a research infrastructure for our division, such as sourcing research staff to help with grant applications.

I will also continue supervising students in the health research methodology program. Likewise, we’ve recently built a fellowship program for infectious disease prevention and control to prepare students and postgraduates before they work in the field.

How does your role contribute to McMaster’s fight against pandemics?

Diagnostics is a key to addressing the AMR pandemic and reducing unnecessary antibiotics, but it’s one of our biggest gaps in treatment.

I’m currently collaborating with researchers in IIDR and Canada’s Global Nexus for Pandemics and Biological Threats to discover faster diagnostics for urinary tract infections (UTI). It can take two or three days to know the best antibiotic to prescribe for UTIs. A much quicker diagnostic test that identifies which pathogen you’re dealing with can help inform the right choice of antibiotic at the onset. You can even avoid those first few days of patients taking broad-spectrum antibiotics.

But how can we improve our diagnostics? Maybe there’s something from an engineering perspective that we can implement physically within a clinical setting to improve diagnostics? Or maybe mobile technology could help? Our team is engaging in these types of conversations from a bench-to-bedside mindset to uncover the solutions to identifying infections more quickly.

From a clinical perspective, we’re also trying to understand the most appropriate PPE and other measures for different settings, which will better prepare us for the next pandemic.

What would you say is the impact of the funding for this chair?

Prior to the pandemic, infectious diseases weren’t top of mind for the general public. The late Mr. Michael DeGroote had visionary leadership and an understanding for the importance of supporting infectious disease research before it became a mainstream concern.