How can I tell if I have norovirus? Expert explains symptoms

The highly contagious norovirus is spreading across Canada, with some symptoms overlapping with other viruses.

The number of reported norovirus cases are higher this year compared to the five-year historical average in the country, according to the Public Health Agency of Canada (PHAC).

CTVNews.ca spoke with a health expert to find out how you can tell you have norovirus, the most common form of stomach flu, and what to do if you have it.

What is norovirus?

Norovirus, also known as “Norwalk virus,” was named after the first outbreak that occurred in Norwalk, Ohio.

It spreads easily and quickly, according to PHAC. Just a few virus particles from an infected person's feces or vomit can make a person sick. For instance, you can get it by touching a contaminated surface and then touching your mouth before washing your hands, or by eating contaminated food and drinks.

Symptoms: How to tell if it's norovirus or something else

Dr. April Kam, interim division head for pediatric emergency medicine at McMaster Children's Hospital in Hamilton, Ont., said norovirus has symptoms that may overlap with other viruses. Kam is also an associate professor with McMaster University's department of pediatrics.

As norovirus is a gastrointestinal bug, people tend to have nausea, diarrhea and belly pain, Kam said in a video interview with CTVNews.ca.

The other main symptoms of norovirus are cramps and vomiting. Vomiting is more common in children than adults, according to PHAC.

Less common signs you may have norovirus can include low-grade fever, chills, headache, body and muscle aches, and fatigue.

"There is overlap with influenza as well, where you have ... many days of fever, the muscle soreness, headache, all that stuff," she said.

It can be hard to tell whether you have norovirus or influenza, but you are less likely to mistake a cold for norovirus.

If you have a rhinovirus infection, which typically causes the common cold, you tend to have nasal congestion, cough or fever, Kam said.

Health experts like Kam recommend people who think they have norovirus stay home and avoid having contact with others until at least two days after they no longer have symptoms.

What to do if you or your child has norovirus

Kam said it's not as important to know whether you have norovirus as it is to manage the symptoms.

She said the key is remaining hydrated by drinking lots of fluids, including both water and other liquids with electrolytes or diluted juice. For instance, Pedialyte, Gatorade and Powerade are some types of liquids that can help prevent dehydration by restoring the important salts and minerals you may be losing from vomiting and diarrhea, she said.

"This is the time where you can let the kids eat the popsicles and the freezies and things like that if that's all they want, just to keep hydrated," Kam said.

She doesn't recommend drinks with a lot of sugar, like pop, as the sugar may exacerbate symptoms like diarrhea, she said.

Kam said to keep yourselves comfortable, you can take pain relievers like ibuprofen or acetaminophen, known by the brand names Advil and Tylenol, respectively.

Although no prescription medication exists to treat norovirus, most people start to feel better within two to three days, according to PHAC.

Young kids should be able to produce tears when they're crying, their lips and tongue should still be moist, and they should be peeing normally, she said. If there are changes, it could indicate issues with hydration.

People should see their family physician in certain cases, Kam said. "I feel like if you're worried about your hydration, or if you're worried about your child's hydration or lethargy or disproportionate pain or something, then you should see a doctor."

Norovirus prevention

Simple things can be done to help protect yourself and your family against norovirus.

Frequent hand washing with soap and water is the key advice Kam offered to those worried about catching it.

Food safety, such as ensuring vegetables are properly washed, and disinfecting surfaces and toys are important as well, she added.

With files from CTV News Toronto's Hannah Alberga