Norovirus is the most common cause of gastroenteritis foodborne illness in the U.S., causing more than 21 million illnesses each year, approximately 700,000 hospitalizations, and 800 deaths. This highly infectious virus is transmitted very easily from person to person as well as from food that has been cross-contaminated by an infected food handler. This knowledge sheet focuses on norovirus, the disease it causes, prevention, and response to potential norovirus contamination.
Norovirus is the pathogen responsible for approximately 60% of the gastroenteritis illnesses from known pathogens, according to the U.S. Centers for Disease Control and Prevention (CDC).
Noroviruses are present in the feces and vomitus of infected people in very high concentrations. Since viruses are so small, they can spread in the air to approximately 25 feet from the location where an ill person vomits.
The acute gastroenteritis illness that norovirus causes has a brief incubation period of 12 hours to 48 hours with the duration of the illness lasting only 1 – 2 days. The virus may be present in feces for 2 weeks after symptoms subside.
Symptoms include: vomiting; nausea; abdominal cramps; diarrhea; headache; and sometimes fever, chills, and muscle aches.
The populations at most risk are the elderly, the very young, and the immunocompromised. Dehydration and other complications may cause severe illness or death.
Foodborne norovirus outbreaks occur most often in foodservice establishments or catered events due to food handlers being ill, not properly washing their hands, and cross-contaminating ready-to-eat foods.
Examples of foods implicated in outbreaks are salads, sandwiches, and baked goods. Icings or liquid foods such as salad dressings can be responsible for outbreaks as the virus may become distributed throughout the product and contaminate a large amount of food.
Undercooked shellfish such as oysters harvested from norovirus-contaminated water have caused a number of outbreaks. Produce items harvested from areas where contaminated irrigation water is used have also caused norovirus transmission.
KEEP OPERATIONS & CUSTOMERS SAFE FROM NOROVIRUS
One of the best ways to prevent the spread of norovirus is through the use of proper handwashing techniques.
Require all food handlers to wash their hands frequently and properly, especially before preparing or handling any food, before and after preparing or handling raw shellfish, after using the restroom, or after cleaning the restroom.
Ill guests may contaminate restrooms, so use disinfectant with efficacy against the norovirus when cleaning the restroom.
Enforce a policy of no bare hand contact for ready-to-eat foods – disposable gloves, deli paper, tongs, etc. – and handwashing prior to putting on gloves.
Do not permit employees to work when ill with vomiting and diarrhea or diagnosed with any of the CDC’s “big six” foodborne pathogens – Non-Typhoidal Salmonella species, Salmonella Typhi, Shigella species, Shiga Toxin-producing E. coli, hepatitis A, or norovirus. Do not permit employees to return to work until they are symptom-free for at least 48 hours.
Do not serve undercooked shellfish unless there is a consumer advisory on the menu. The U.S. Food and Drug Administration recommends shellfish be cooked using one of the following methods: boil for 3 minutes; fry in oil at 375°F for 10 minutes; or bake at 450°F for 10 minutes.
Immediately follow-up on any customer foodborne illness claims. Alert health department if multiple reports are received so that any potential outbreaks can be investigated quickly.
Have a written plan to respond to potential norovirus contamination such as vomiting or diarrheal incidents. (Download Steritech’s White Paper: Guidelines for Response to Vomiting & Diarrheal Incidents in Foodservice Establishments):
Remove all persons from area; discard any exposed food (in preparation or in service) within 25 feet of a vomiting or diarrheal incident. Include any linens, carpet, and all surfaces exposed in disinfection procedures.
Have a bodily fluid clean-up kit with personal protective equipment, disinfectant effective against norovirus, and disposable clean-up tools and containment bag.
Train employees on proper disinfection and clean-up procedures.
Monitor any employees involved in clean-up for 48 - 72 hours for any symptoms of norovirus.
IMPORTANT FACTS ABOUT NOROVIRUS FOR LOCATION EMPLOYEES
One of the most important ways you can prevent norovirus is through frequent, proper handwashing.
Know where to find your location’s bodily fluids clean-up kit and understand procedures for responding to a vomiting or diarrheal incident.
If a vomiting or diarrheal incident occurs at your location, disinfect all hard surfaces to kill norovirus. Examples: counters, tables, chairs, drink dispensers, door handles, touch pads, etc.
Standard foodservice sanitizers will not kill norovirus; the chart on page 2 lists effective disinfectant solutions. Food contact surfaces must be rinsed in water after disinfection and before use.
Do not come to work when you are sick. Norovirus is highly contagious and you could contaminate food or others.