Disinfection tolerance of C. perfringens on farms and in processing

Clostridium perfringens is a Gram-positive, aerotolerant anaerobic spore-forming bacterium that causes a wide variety of diseases in humans and animals, primarily as a result of its ability to produce many different toxins (Markey et al., 2013). In humans, C. perfringens is responsible for gas gangrene, enteritis necroticans, food poisoning, and antibiotic-associated diarrheas ( Myers et al., 2006). Currently, C. perfringens type A food poisoning ranks as the second most commonly reported foodborne illness in Canada (Thomas et al., 2013).

c-perfringens-farmIn poultry, avian-specific C. perfringens strains cause necrotic enteritis, an economically significant poultry disease that costs the global industry over $2 billion annually in losses and control measures (Stanley et al., 2014). In some countries, this disease appears to be on the rise because of removal of antibiotic growth promoters (Stanley et al., 2014). C. perfringens is also a cause of various enterotoxemia in other animal species. Isolates of animal origin constitute a risk for transmission to humans through the food chain.

In order to persist in the environment, many bacteria have evolved the ability to form biofilms (Davey and O’Toole, 2000 and Jefferson, 2004). In fact, the predominant organizational state of bacteria in nature is biofilms (Costerton, 1999). Important features of cells in biofilms include: aggregation in suspension or on solid surfaces, increased antibiotic tolerance, and resistance to physical and environmental stresses (Davey and O’Toole, 2000, Davies, 2003 and Hall-Stoodley and Stoodley, 2009). It is now generally accepted that the biofilm growth mode induces bacterial tolerance to disinfection that can lead to substantial economic and health concerns (Bridier et al., 2011). Although the precise mechanism of such tolerance remains unclear, a review has recently discussed the subject as a multifactorial process involving the spatial organization of the biofilm (Bridier et al., 2011). More recently, we, and others, have described the formation of biofilms in C. perfringens (Charlebois et al., 2014 and Varga et al., 2006). We demonstrated that the biofilm formed by C. perfringens could protect the cells from an exposure to atmospheric oxygen and to high concentrations of antibiotics and anticoccidial agents ( Charlebois et al., 2014). It has also been observed that the biofilm formed by C. perfringens could protect the cells from an exposure to 10 mM of hydrogen peroxide even though this bacterium is catalase-negative (Varga et al., 2006). The capacity of C. perfringens to be part of dual- or multi-species biofilm has recently been reviewed ( Pantaleon et al., 2014) and C. perfringens biofilm was detected in many types of multi-species biofilm including biliary stents (Leung et al., 2000 and Pantaleon et al., 2014).

However, susceptibilities of C. perfringens mono- and dual-species biofilms exposed to most disinfectants are currently unknown. This study was undertaken to investigate the tolerance of C. perfringens mono- and dual-species biofilms to disinfectants used in farms and food processing environments.

Tolerance of Clostridium perfringens biofilms to disinfectants commonly used in the food industry

Journal of Food Microbiology

Volume 62, April 2017, p. 32-38

Charlebois, Audrey. Et al.


Slimer in the Kitchen: Salmonella biofilm means more work when using disinfectants

Who you gonna call? GHOSTBUSTERS! Or – a professional cleaning company.

My favorite character from the Ghostbusters series is Slimer, mainly because he always seems to get away with causing chaos around him. As a kid, I didn’t think too much about his puke-green color or possible germs that he might be carrying. However, after reading an article from the Norwegian School of Veterinary Medicine about Salmonella biofilms, I’ve come to the conclusion that Slimer was probably a giant lump of Salmonella coated in a protective biofilm.  Bacteria have multiple forms of defense, and some bacteria are able to produce a biofilm, or a slimy outer covering, in order to protect itself from disinfectants and to ensure its survival in the environment.  Too bad the Ghostbusters guns didn’t have alcohol and Virkon in them, otherwise Slimer would be toast.
In her doctoral thesis, Lene Karine Vestby studied why it is so difficult to get rid of once they have managed to establish themselves in Norwegian feed and fish meal factories. She discovered that bacteria efficient at forming biofilm (bacteria coating) survived for longer in the factories than those that had a reduced ability to form this coating. The ability to survive in factories therefore appears to be connected with the ability to form a biofilm and it would seem that removing biofilm is a necessary step towards eradicating from the factories.
Vestby studied the effect of nine most frequently used disinfectants and found that their efficiency is substantially reduced of the Salmonella has managed to form a biofilm. The effect of the majority of the disinfectants was then no longer satisfactory, but a product containing 70% ethanol was the most efficient, followed by one called Virkon S. These results could improve the efficiency of the cleaning procedures used by processing plants in the animal feed industry, and also in the human food industry.
Of course it’s not just about finding the right tools, the tools must be properly used. Proper production methods should be in place to prevent the contamination of the feed. Processing and packaging facilities should follow a regular cleaning schedule with the appropriate disinfectants. These things all contribute to the culture of food safety. They should also keep Slimer out of the kitchen.