What to know about norovirus, the ‘stomach bug’ that’s going around

If you or someone in your family has been sick with a “stomach bug” lately, you’re not alone. Norovirus cases have seen an uptick around the country this winter, according to the Centers for Disease Control and Prevention.

And Wisconsin is no exception. The state Department of Health Services reported a record-high number of norovirus outbreaks in December, including a campus outbreak at the University of Wisconsin-Eau Claire. Earlier this month, a long-term care facility in Kaukauna reported a norovirus outbreak among its residents.

Norovirus is a gastrointestinal virus that causes an infection within the GI tract. Common symptoms are vomiting and diarrhea, but people can also experience fever, abdominal pain and other symptoms.

“Norovirus is absolutely miserable,” Megan Meller, an infection preventionist at Gundersen Health System, recently told WPR’s “Wisconsin Today.” “If you’ve ever had it, you never want it again.” 

The good news, she said, is that it resolves quickly, with the worst symptoms lasting only a day or two. “Wisconsin Today” spoke to public health experts to learn more about what norovirus is, how health officials track it, and strategies for treating it and preventing it from spreading.

How norovirus spreads

Norovirus spreads largely through contact with an infected person or a contaminated surface, or by ingesting something with virus particles in it. A person infected with norovirus “sheds” particles through fecal matter and vomit, and these particles can live for months on surfaces.

“It’s kind of horrifying just how easy norovirus can spread itself out into the environment,” Meller said. “It hangs out in the environment, and then someone comes along and they touch a table, they touch something in the bathroom and it looks clean.” 

If that person then touches their face or eats or prepares food without proper hand hygiene, the virus gets transmitted and the “vicious cycle” continues.

Another reason norovirus is highly contagious is because just a few particles can lead to an infection.

“It takes about 10 virus particles, which in the virology world is literally next to nothing,” Meller explained. 

Norovirus often makes its way through an entire household once one person is sick “because of how little it takes to get infected and how easily it spreads,” she said.

Tips for stopping the spread

While it’s very difficult to contain norovirus once someone in a household is sick, Meller offered a few recommendations:

• If possible, have the sick members of the household use a separate bathroom.
• Disinfect high-touch surfaces like door knobs, handrails, light switches and faucets with bleach.
• Read the label on disinfectant wipes and sprays to make sure that it kills norovirus. The U.S. Environmental Protection Agency maintains a list of products that are effective against norovirus. 
• Wash laundry with hot water.

Ditch the hand sanitizer and wash your hands

The biggest thing you can do to protect yourself and others from norovirus? Wash your hands.

“In my job as an infection preventionist, it’s all about hand hygiene,” Meller said. 

She explained that unlike some other viruses, norovirus cannot be removed with hand sanitizer or alcohol gel. That’s because norovirus has a protein shell rather than a lipid membrane. 

The best way to remove norovirus from your hands is to wash with soap and water for at least 20 seconds.

“We’ve been taught hand hygiene with soap and water since we were children,
Meller said. “But I think (it has) just become such a daily habit that we don’t realize that you actually need to wash your hands for longer than most of us are probably already doing, so 20 seconds minimum.”

Another thing Meller sees a lot in her work is people not washing thoroughly enough to cover the whole hand. She said it’s important to wash the top of the hands, the palm, the fingertips, under the nails and between the fingers — areas she said are commonly missed. 

When to seek medical assistance

While norovirus is not generally life-threatening, the CDC reports that it causes 900 deaths and 109,000 hospitalizations on average every year. The biggest risk is dehydration, which is more likely to affect young children, older adults and people who are immunocompromised.

Meller recommends going to urgent care or the emergency room if you or your child can’t keep enough liquids down to urinate at regular intervals or are showing any other signs of dehydration.

Otherwise, the best treatment is to rest and stay hydrated. Meller recommends aiming for drinks with sodium or electrolytes, like Pedialyte, Gatorade or broth.

“Anything that your stomach might be able to handle keeping down are things I would reach for right away,” she said.

Tracking norovirus

Tracking how widely norovirus is spreading can be challenging, because it’s not considered a “notifiable disease” that requires doctors to report infections, said Malia Jones, a public health researcher in the department of Community and Environmental Sociology at UW-Madison.

However, outbreaks in congregate settings do get reported to and investigated by local public health departments as part of their routine operations. Jones said this “public health surveillance” is an important first defense officials have to know what illnesses are going around and what might be coming down the pike. 

Is a norovirus vaccine on the horizon?

It has been difficult to develop a norovirus vaccine because, as with the common cold, there are so many rapidly changing variants in circulation that it is hard to identify which strains to protect against.

However, Jones said that new mRNA technology — which was used to create the first COVID-19 vaccines — is showing promise for this because it can address diseases with a lot of subtypes. Moderna is currently moving forward with a phase 3 trial of an mRNA norovirus vaccine.

While it may not seem urgent to develop a norovirus vaccine because of its low fatality rate, Jones said public health officials take norovirus seriously as a public health problem.

“If you’ve ever had norovirus, you know that even if you don’t die of it, it’s really unpleasant, and you usually miss a few days of work. Kids miss a few days at school,” she said. “That kind of disruption, we also consider a big population health problem.”