It’s unlikely to be a surprise to anyone who receives this newsletter that noroviruses are the most common cause of epidemic gastroenteritis. But did you know that, according to CDC, they are responsible for at least 50% of all gastroenteritis outbreaks worldwide and are a major cause of foodborne illness? Did you know that approximately 21 million illnesses attributable to norovirus are estimated to occur annually? And even if you know these facts … do you know what to do in case of an outbreak in your facility?  And how to clean up the potential vomit and diarrhea that can result from an employee – or customer – sickened with the virus? How much do you need to do? – it is likely more than you think. One point to keep in mind with norovirus is that it takes very few viral particles to make someone sick. Estimates are that as few as 10 virus particles are enough to cause illness, and when someone vomits there are literally tens of millions of viral particles floating around. So it’s no wonder this virus spreads so easily. Over the past few months, there has been an increasing worry with our clients about norovirus and we, at TAG, have been reviewing the latest scientific literature and are actively engaged with several research groups who are working on many aspects of the virus. These include norovirus survival, proliferation, spread, inhibition, inactivation, detection, and attachment on various types of surfaces, as well as solutions for cleanup and contamination mitigation, including evaluation of chemical concentrations and exposure times needed to kill norovirus and new intervention technologies that may be available in the near future. While we do know that norovirus has been shown to persist on surfaces such as stainless steel for more than six weeks – with even greater persistence at cold temperatures, there is no clear consensus on what the exact clean-up perimeter should be for any surface. This is because there are many factors that can affect the area potentially contaminated with viral particles, such as type of vomit, volatility of vomit, amount of aerosolization, foot traffic, ventilation (air flow), etc. That said, most experts propose at least a 25-foot perimeter for cleanup after a vomit or diarrhea event, as indications from past outbreaks are that airborne particles can contaminate environmental surfaces up to 25 feet from the source. Additionally, a report from the Colorado Department of Public Health & Environment states: “Any commonly touched surfaces (like door knobs, hand rails, elevator buttons, faucet handles, etc.) in the vicinity (within a 25-foot radius) of where the vomit or fecal accident occurred should be wiped down with the bleach solution effective against norovirus.” While there are no studies that directly investigate the cleanup perimeter question, other reports that prescribe similar action include CDC’s Clean-up for vomiting and diarrheal event in retail food facilities; Dekalb County Board of Health Recommended Cleaning Procedures for norovirus Outbreaks; and norovirus Information Guide – A collaborative study by the Food Marketing Institute (FMI) and Ecolab. Additionally, given that small droplets of the virus can float around the environment and persist in the air for a fairly long time, we see the best, and safest, strategy as being cleanup of the entire room and possibly the entire facility, because the infected person may have gone to the bathroom and deposited virus there, not washed his or her hands afterward and touched other surfaces in the facility, etc. Obviously, this idea has to be taken with a large dose of practicality and norovirus is much more of a problem at the food service end of the food chain than in manufacturing and processing. But if you are making a ready-to-eat food, then having a good clean-up protocol in place for vomiting episodes on the production floor is a good idea. To ensure you are prepared when a case of norovirus hits your facility (with 21 million illnesses a year in the U.S. alone, the odds are pretty good that it will), we see the advice of the FMI/Ecolab report as being very beneficial. That is, “In an establishment where food is handled, having a written plan and being prepared to implement the plan are important elements to effectively respond to and manage situations potentially involving norovirus contamination.” This would include having all employees trained and having clean-up equipment on hand, including personal protective equipment as well as applicable clean-up chemicals and tools. Additionally, anytime norovirus is even suspected as the cause of vomiting or diarrhea, it should be treated as potentially infectious material. Thus, the first step for any incident should be to immediately cover the vomit or diarrhea with a disposable cloth, paper towels or other absorbent material to reduce the spread of airborne contamination, then begin clean-up protocols. Other recommendations from Michigan’s Barry-Eaton District Health Department which were issued after a restaurant outbreak in its area were for the facility to: Discard any exposed food or single-service articles within at least a 25-foot radius, and disinfect the surface areas with a bleach solution. Immediately close restrooms used during or after a vomiting incident until they are completely disinfected. Exclude ill employees from work for at least 72 hours after symptoms subside; then restrict them from handling kitchenware or ready-to-eat food for an additional 72 hours. Consider partial or complete closure of the restaurant after an incident to enable thorough disinfection. Two good resources that highlight other critical factors you should consider are National Advisory Committee on Microbiological Criteria for Foods (NACMCF): Response to Questions Posed by the FDA, FSIS, CDC, NMFS, and DDVS Activity Regarding Control Strategies for Reducing Foodborne Norovirus Infections and CDC’s Updated Norovirus Outbreak Management and Disease Prevention Guidelines. About The Acheson Group (TAG) Led by Former FDA Associate Commissioner for Foods Dr. David Acheson, TAG is a food safety consulting group that provides guidance and expertise worldwide for companies throughout the food supply chain. With in-depth industry knowledge combined with real-world experience, TAG’s team of food safety experts help companies more effectively mitigate risk, improve operational efficiencies, and ensure regulatory and standards compliance. www.AchesonGroup.com
