Norovirus
Clinical Name: Norovirus
Common Name: Stomach bug or stomach flu (not related to influenza)
What Is Norovirus?
Norovirus is a highly contagious virus that causes acute gastroenteritis—an inflammation of the stomach and intestines. It leads to vomiting and diarrhea, and is the leading cause of foodborne illness in the United States.
It spreads quickly through contaminated food, water, surfaces, and person-to-person contact. Just a tiny amount of virus is enough to make someone sick.
Source: CDC, WHO
Introduction
Nicknamed the "stomach bug," Norovirus is responsible for millions of cases of vomiting and diarrhea each year in the U.S. It’s especially common in food service environments due to its ability to survive on surfaces and resist many disinfectants.
For food workers, norovirus presents a serious risk. It spreads easily from hands to food, and even a microscopic amount can trigger outbreaks in restaurants, schools, and cruise ships.
Why It Matters
Norovirus causes an estimated 19–21 million illnesses, 465,000 ER visits, and 900 deaths annually in the U.S. It can persist on surfaces for weeks and requires strict hygiene and sanitation protocols.
Food Source Examples
| Food Source | Examples |
|---|---|
| Contaminated ready-to-eat foods | Salads, sandwiches, bakery items |
| Raw shellfish | Oysters, clams, mussels |
| Produce | Berries, leafy greens |
| Infected food handler | Any food touched by unwashed hands |
Symptoms
Symptoms typically begin 12 to 48 hours after exposure and last 1 to 3 days. Dehydration is a common complication.
Symptom Details
| Symptom | Details |
|---|---|
| Diarrhea | Frequent, watery stools |
| Vomiting | Sudden and intense |
| Nausea | Feeling sick to your stomach |
| Stomach pain | Cramping, often with bloating |
| Fever/headache/body aches | May occur in some cases |
| Dehydration | Dizziness, dry mouth, low urination, fatigue |
Children and older adults are especially vulnerable to dehydration. Seek medical help if symptoms are severe or persistent.
Who’s at Risk
Norovirus affects people of all ages and spreads easily in crowded places. The following groups are especially vulnerable:
- Young children and infants – High risk of severe dehydration
- Older adults – Increased chance of complications
- People with weakened immune systems – More likely to suffer longer and more severe illness
- Food handlers – Can unknowingly spread virus via contaminated hands or surfaces
- Raw shellfish consumers – Oysters and clams can contain norovirus if not properly cooked
How It Spreads
- Person-to-person contact – Touching, caring for, or shaking hands with someone who’s sick
- Contaminated food or water – Often from infected handlers or contaminated sources
- Touching surfaces – Virus can live for weeks on counters, doorknobs, and utensils
- Improper handwashing – Primary cause of spread in food environments
A person can still spread norovirus for 2 weeks or more after symptoms go away.
How to Prevent It
Preventing norovirus requires strict personal hygiene and sanitation practices.
| Step | Action |
|---|---|
| Clean | Wash hands with soap and water for at least 20 seconds |
| Separate | Avoid preparing food for others while sick or for at least 48 hours after symptoms end |
| Cook | Cook shellfish thoroughly; avoid raw oysters and clams |
| Disinfect | Use bleach-based cleaners on surfaces touched by sick individuals |
Tip: Alcohol-based hand sanitizers are less effective—soap and water is best.
Cleaning Measures
Norovirus is tough. It can survive freezing, heating, and many common disinfectants.
- Clean and disinfect all kitchen surfaces with a bleach solution or EPA-approved disinfectant
- Wash dishes and utensils with hot, soapy water
- Wear gloves when handling laundry, and wash soiled items in hot water
- Dispose of vomit or fecal matter carefully to avoid aerosol spread
Tip: Use disposable gloves and masks when cleaning contaminated areas. Disinfect everything, even doorknobs and light switches.
Protect Your Kitchen. Protect Your Business.
Norovirus outbreaks are devastating—and avoidable. With the right training, your foodservice team can identify risks and act fast to stop the spread before it starts.
👉 Train your team with Certivance
