A Pharmax Q&A Session About Biofilms

February 25, 2014

Q1: “What is the latest evidential research on infection control?”

A1: Many leading experts in infection control are confounded by the rapid increase in hospital-acquired infections. Recent evidence suggests that as many as 85% of all hospital-acquired infections somehow relate to the presence of a biofilm.

Q2: “What is the significance of these biofilms?”

A2: Testing antimicrobials to determine their effectiveness (the first line of defense against hospital-acquired infections) is based entirely on a single organism in its planktonic (free-swimming) state. These same organisms in a biofilm state are 10 to 1000 times more resistant to these same antimicrobials.

Q3: “What are the challenges of biofilms?”

A3: Clearly, if we have any hope of reducing hospital-acquired infections, we must discover how to prevent or destroy these bacterial biofilms. The challenge lies in the structure of a biofilm itself and how it shields and protects not only bacteria, which cause its formation, but also other harmful organisms, such as viruses, fungi, etc., that view the biofilm as a kind of condominium habitat available to all.

Q4: “I don’t really understand the whole notion of a biofilm. What is it exactly?”

A4: Our image of bacteria is isolated cells swimming around in an aqueous milieu. Not only is this misleading, but, in the case of infectious diseases, it is dangerous. In nature, the majority of organisms live together in large numbers attached to a surface. Rather than lonely hermits in their planktonic form, most bacteria spend much of their lives in the microbial equivalent of a gated community – a biofilm. The residents of the biofilm may be a single species or a very diverse group of microorganisms distributed into various neighbourhoods. Their common bond is a slimy matrix made of polysaccharides, DNA, and proteins, which, together, form an extracellular polymeric substance that envelopes and protects the residents from outside invaders such as antimicrobials and antibiotics.

Q5: What resources can you utilize to conquer the challenges and how does innovation help you to overcome those challenges to reach the end goal?”

A5: Firstly, it is foolhardy to suspect that we can overcome these challenges created by the existence of biofilms. Our best hope is to utilize innovation to “control” rather than “overcome” these challenges. Our research partners at the University of Calgary, Ryerson University, and the University of Guelph have enabled a better understanding of the structure, life-cycle, and behaviour of biofilms. Since the slimy protective coating is an exopolysaccharide, a complex sugar of sorts, we have been experimenting with engineered enzymes to convert the exopolysaccharide to a simple glucose. Another area of investigation has arisen from the research that reveals that biofilms are generally a response to stressors. When the stressor is removed, the exopolysaccharide breaks down and releases the microorganisms into the surrounding environment. We have been attempting to discover the mechanism and chemistry of this release to be able to replicate it artificially. The most promising control mechanism that we have identified is continual cleaning with specially-formulated chemistry that removes early-stage biofilms that are not fully encased in a mature exopolysaccharide matrix. This chemistry is complex and proprietary at this juncture, but, suffice it to say, both cleaning and disinfecting in concert seems to be part of the key to obtaining better outcomes.

Q6: “Are there any particular areas in healthcare that are at higher risk?”

A6: Perhaps the most common high-risk area is in long, narrow-lumened devices, such as flexible endoscopes. Statistical data seems to point out that more than 40% of colonoscopes present an opportunity for cross-infections to occur due to residual bioburden. This is, almost certainly, as a result of biofilms. The scary truth is the fact that a biofilm can shelter microorganisms in these devices so perfectly that even swabbing the channels will reveal “no growth” – the measure of clean.