Norovirus Infections Are Rising: The Symptoms Doctors Are Most Often Seeing Now

Sick season is getting underway across the United States.

That familiar time of year has arrived.

Data from the Centers for Disease Control and Prevention show that norovirus, a highly unpleasant illness that affects the stomach and intestines, is becoming more common across the country.

“It is the season when it increases,” said Catherine Troisi, an infectious disease epidemiologist at UTHealth Houston. “It’s around all the time, but cases typically increase ... late fall to winter, probably because people are indoors.” That makes it easier for the virus to spread.

“Typically, we see it in two scenarios. The first is in outbreaks from a common exposure, such as when you hear about a lot of people on a cruise ship coming down with nausea and vomiting,” Dr. Donald Dumford, an infectious disease doctor at Cleveland Clinic, told HuffPost via email. “The second is sporadic cases, which seem to be more common in the winter months.”

The virus is also often seen in nursing homes and can spread after people eat raw oysters.

“It’s not necessarily surprising to start to see a rise at this time of year. Outside of those common source outbreaks, such as cruise ships, norovirus is also known as winter vomiting disease,” Dumford added. “We see a usual rise in cases throughout the winter months.”

He said the illness appears to spread more easily in cooler temperatures and can survive longer on surfaces during that period.

Norovirus can lead to very unpleasant symptoms.

Norovirus commonly causes nausea and vomiting, and it can also bring on fever and diarrhea, Dumford said.

Most people are ill for one to three days and recover at home, Troisi said. Staying hydrated is important if you become sick. In some cases, though, the illness lasts longer and can cause complications that need medical care.

“If you start to get fevers, blood in your stool, then call your healthcare provider as those can be signs of a more invasive type of gastrointestinal infection that may need antibiotics,” Dumford said.

If diarrhea or vomiting leaves you lightheaded from dehydration, you should contact a doctor or go to an emergency room, he said, since you may need IV fluids.

Norovirus cases are increasing nationwide.

The virus spreads very easily, but there are ways to reduce your risk.

“It is a very infectious virus,” Troisi said. “It can last on surfaces for up to two weeks, and so it spreads very easily.”

The most effective way to lower your odds of getting sick is to wash your hands thoroughly. “There have been studies about proper hand washing ... a majority of people, including food handlers, do not wash their hands properly,” Troisi said.

That does not necessarily mean people are skipping handwashing altogether, she said, but they may not be removing rings or washing for a full 20 seconds. She said to wash for the length of “Twinkle Twinkle Little Star.”

Using hand sanitizer before a meal is not enough. “Alcohol hand sanitizers are not effective in killing norovirus,” Dumford said.

“Hand sanitizer is great for other pathogens like the flu and COVID and other respiratory viruses, but when trying to prevent the acquisition of some gastrointestinal viruses, including norovirus, soap and water is the standard,” Dumford said.

Troisi said you should wash your hands before eating, after using the restroom, after changing diapers and when caring for sick people. If there is a norovirus outbreak in your community, she added, you should also wash after shaking hands.

If you become sick, keep your distance from others and watch for warning signs.

Good hygiene can lower your risk, but it cannot eliminate it entirely.

If you do get sick, stay away from other people. “If you have vomiting [or] diarrhea, stay home while still sick,” Dumford said. “Also make sure to wash your hands frequently with soap and water to avoid having norovirus on your hands and then contaminating any shared surfaces.”

He also advised avoiding cooking for other people for two to three days after symptoms end, so you do not pass the virus along.

Keep an eye out for warning signs such as dehydration, fever and blood in the stool. If any concerning symptoms appear, seek medical care.

Troisi said a relatively new norovirus strain has been infecting people since earlier in the year.

It is not possible to know exactly how that will affect norovirus levels later on, but she said this year could be somewhat worse than usual because of the new strain.

Children tend to get norovirus more often than adults, but anyone can catch it, making hand hygiene and staying home when sick especially important as sick season continues.