It comes on suddenly, spreads like wildfire, and leaves you feeling weak and weary. Norovirus — commonly known as "stomach flu," although not related to influenza — is a very contagious viral illness that causes vomiting, diarrhea and stomach pain. These symptoms are collectively known as gastroenteritis.
While norovirus gastroenteritis is not the same thing as food poisoning, it can occur anywhere food is served including restaurants and catered events, as well as schools and child care centers.
"Norovirus is the leading type of foodborne gastroenteritis in the United States," says Dr. Neema Shakibai, a family medicine doctor with Sharp Rees-Stealy Medical Group. "It is a very nasty infection affecting 20 million people every year, leading to 400,000 emergency room visits, and tens of thousands of hospitalizations. Like other viral illnesses, such as influenza, the people most at risk for the worst infection are the very young, senior citizens and those with chronic medical issues."
How do you get norovirus?Norovirus is a very contagious virus — only a few microscopic germ particles can get you sick. It is transmitted by:
- Direct contact with an infected person — An infected person can send out billions of viral particles within a wide radius.
- Consuming tainted food or water — This can happen in the fields where food is grown, or if an infected person prepares food.
- Touching contaminated surfaces, then putting your hand in your mouth — This can include dishware, clothes, sheets and towels.
Symptoms typically begin within one to two days after exposure to an infected person or substance.
How do you treat norovirus?As with other viral illnesses, antibiotics will not help you feel better faster if you have norovirus, as they only treat bacteria and will have no effect on viruses.
The best way to treat norovirus is to rest at home and drink plenty of fluids. You will feel very bad for one to three days, although you will remain contagious for several days after you start to feel better.
People with norovirus are at risk for dehydration, especially young children, older adults and people with other illnesses. Symptoms of dehydration include:
- Decreased urination
- Dry mouth and throat
- Feeling dizzy when standing up
- In children, dry eyes with no tears or unusual fussiness
"Patients should be evaluated by a medical professional if they have high fevers, severe pain, black or bloody vomit or diarrhea, or symptoms for severe dehydration such as very little or very dark urine, feelings of passing out, and confusion," says Dr. Shakibai.
Can norovirus be prevented?There is no vaccine to prevent norovirus, but you can help stop its spread with these safety tips:
- Wash your hands
- Wash fruits and vegetables before eating
- Cook seafood thoroughly
- If you are sick, stay home and don't prepare food for other people
- Clean and disinfect after someone is sick, using a bleach solution on any surface touched, including doorknobs, sinks, toilets, portable devices and furniture
- Thoroughly wash affected clothes and linens in hot water
"You can try to reduce your risk for a norovirus infection by keeping your fingers away from your mouth and always washing your hands very well with soap and water," says Dr. Shakibai. "Alcohol-based hand gels are not as effective as soap and water against norovirus, which can easily and rapidly spread from person to person."