5.5 Million Cases of Norovirus are Spread Via Food Each Year

By Kim Smiley

Norovirus outbreaks on cruise ships may make exciting headlines, but the reality is that only one percent of norovirus outbreaks occur on the high seas.  About 20 million people in the US are sickened by noroviruses in the US each year and one of the most common transmission paths is via food.  Food-borne norovirus is estimated to be responsible for 5.5 million cases of norovirus annually in the US.

A Cause Map, a visual method for performing a root cause analysis, can be used to analyze this issue.  The first step in the Cause Mapping process is to determine how an issue impacts the overall goals and then the Cause Map is built by asking “why” questions to visually lay out the cause-and-effect relationships.  In this example, we’ll focus on the safety goal since it is clearly impacted by 5.5 million cases of norovirus transmitted via food.

So why are people getting norovirus from food?  This is happening because they are consuming contaminated food, predominantly at restaurants or catered events.  The food becomes contaminated when a food worker’s hands are contaminated by norovirus and they touch food, particularly food that is ready to serve and won’t be cooked prior to consumption.  (Disclaimer: You may want to stop reading here if you are eating or thinking about going to out to eat soon.)

For those unfamiliar with the illness, norovirus is basically a gastrointestinal nightmare that can cause the human body to do very messy things.  If a food service worker is ill, the virus can get on their hands, especially after using the bathroom.  According to a Centers for Disease Control and Prevention (CDC) report, the transmission of food-borne norovirus is “primarily via the fecal-oral route.”  And that is more than enough said about that.

It is also worth asking why food workers are at work if they are under the weather.  In the US, few food service workers get paid sick leave so they may show up at work sick because they are concerned about the loss of income and the impact on their jobs.  It’s also important to ensure that workers understand the importance of good hygiene and have access to both water and soap and time to effectively wash their hands.

The final step in the Cause Mapping process is to develop solutions to reduce the risk of the problem recurring.  The solutions to this problem are both simple in concept and difficult to effectively implement.  Ideally, food workers should stay home when they are ill and for at least 48 hours afterwards, but this is much easier said than done for many people.  Food workers should also wash their hands after using the bathroom and before handling any food, but it can be difficult to enforce the policy because employers and managers aren’t (and shouldn’t be) closely monitoring what happens during bathroom breaks.

To view a high level Cause Map of this issue, click on “Download PDF” above.