Every winter, it sweeps through schools, cruise ships, and households like an unwelcome houseguest: norovirus, the ultra-contagious stomach bug that can turn a perfectly normal week into a few days of misery. While many dismiss it as just another “stomach flu,” norovirus is the most common cause of stomach bugs and the leading cause of vomiting and diarrhea in the United States, responsible for up to 21 million cases annually. Just a few virus particles – even fewer than 100 – are enough to cause illness, making it one of the most efficient troublemakers in the viral world.
Whether you’re trying to avoid catching it or already in its grip, understanding norovirus is your first line of defense against this gut-wrenching invader. Despite its prevalence and impact, many people don’t know the basics about this resilient virus. Tryon Medical Partners internal medicine specialist Dr. Kennelly shares how it spreads, how to prevent it, and how to treat it if you do encounter it.
What is norovirus?
Norovirus is a widespread and highly infectious virus that leads to symptoms like nausea, vomiting, and diarrhea that typically resolve within three days. It transmits readily through close personal interaction or from contaminated items and surfaces. There is currently no vaccination available for norovirus, but there are vaccine trials underway in an attempt to develop one.
When and how does norovirus spread?
Dr. Kennelly explains that norovirus spreads easily in close, compact areas – which is why it spreads like wildfire at daycares, schools, hospitals, nursing homes, and on cruise ships. Because it spreads fastest indoors, it’s more common to see norovirus in the fall and winter, but it can happen any time of year.
“Norovirus isn’t like the flu, which is really only common in the fall and winter,” Dr. Kennelly notes. “It is more of a situational virus rather than a seasonal one.”
What are typical stomach bug symptoms?
Dr. Kennelly says typical norovirus symptoms include:
- Abdominal cramping
- Low grade fever
- Diarrhea
- Vomiting
Unlike a more traditional cold or flu, norovirus symptoms are almost always gastrointestinal and rarely include runny nose, cough, or sinus congestion.
How do I know when it’s food poisoning vs. the stomach bug?
The main difference between norovirus and food poisoning is the timing of symptoms and how long they last, Dr. Kennelly explains:
- Norovirus: Symptoms usually begin within 48 hours after exposure to the virus, but may appear as early as 12 hours.
- Food poisoning: Symptoms typically develop within 6 hours of consuming contaminated food, and food poisoning rarely lasts more than a day or even a few hours.
Dr. Kennelly says that it’s also helpful to know if your symptoms are norovirus or another virus like the flu or COVID-19. You can take a test to see if it’s other viruses. Once you’ve ruled out the other major virus options, you can assume you have norovirus and treat it accordingly.
“It’s common to hear patients calling norovirus the stomach flu,” Dr. Kenelly notes. “However, it has nothing to do with ‘influenza’ (which is what ‘flu’ is short for) so it’s better to describe it as a stomach bug or virus.”
How can I prevent norovirus?
Dr. Kennelly recommends the following ways to keep norovirus from spreading to you and your family:
- Wash your hands. Make sure to wash your hands thoroughly and often (especially before meals or touching your mouth and nose).
- Stay home when sick. If you’re feeling under the weather, or someone in your family is, stay home rather than going out. This will help you recover quickly and prevent others from getting sick.
- Stay away from buffets. Norovirus can transfer when you come into contact with something that someone with norovirus has touched. Buffets, where food and utensils come into contact with many people, are a common location of norovirus spread.
How long does norovirus last and how do I best treat it?
Norovirus symptoms tend to last 1-3 days. Dr. Kennelly recommends the following to treat the typical symptoms:
- Nausea: Consider taking an anti-nausea medication, either prescribed by your clinician or over the counter. Eating a bland diet (think plain chicken and rice) will help your body get nutrients without upsetting your stomach. Ginger chews and ginger ale can also help settle an upset stomach.
- Diarrhea: The key with diarrhea is to stay hydrated so you don’t get behind on fluid intake. Consider sipping on water and electrolyte drinks. If you notice any of the following symptoms, contact your clinician or go to the emergency room where they can provide support with fluids.
- Dizziness when going from sitting to standing
- Elevated heart rate
- Faintness or lightheadedness
“If you’re healthy, you should recover in 48 hours and feel okay,” Dr. Kennelly emphasizes. “However, children and older adults may struggle more with dehydration symptoms, which can prolong their symptoms.”
How can I advance medicine with the Javara trial?
There isn’t an antiviral treatment for norovirus yet, which makes vaccination development even more important – to help prevent people from getting sick in the first place. This is especially critical for children and older adults who are more vulnerable to symptoms like dehydration.
If you’re interested in helping to advance science, fill out our clinical research partner’s interest form to take part in a norovirus vaccination clinical trial today.
And if you still have questions on norovirus, what it is, and how to prevent it, use MedChat or call Tryon Medical Partners to meet with a clinician.