Norovirus: What you should know

3 experts help shed light on highly contagious virus that impacts millions

Preventing norovirus infection

Practice proper hand hygiene: Wash your hands carefully with soap and water — especially after using the toilet and changing diapers, and always before eating, preparing, or handling food. Alcohol-based hand sanitizers can be used in addition to hand washing. But, they should not be used as a substitute for washing with soap and water.

Wash fruits and vegetables and cook seafood thoroughly: Noroviruses are relatively resistant. They can survive temperatures as high as 140°F and quick steaming processes that are often used for cooking shellfish.

If sick, stay away from food: Keep sick infants and children out of areas where food is being handled and prepared. When you are sick, do not prepare food or care for others who are sick. Many local and state health departments require that food handlers and preparers with norovirus illness not work until at least 2 to 3 days after they recover. If you were recently sick, you can be given different duties in the restaurant, such as working at a cash register or hosting.

Clean and disinfect contaminated surfaces: After throwing up or having diarrhea, immediately clean and disinfect contaminated surfaces. Use a chlorine bleach solution. Immediately remove and wash clothes or linens that may be contaminated with vomit or stool (feces).

Source: CDC

Angie Riley was completely blindsided by her daughter’s sudden illness.

“She was completely fine when she went to bed, no symptoms at all,” Riley said. “Around 4 a.m. she comes in and says, ‘Mommy, my stomach hurts.’”

It wasn’t long before the vomiting began. Riley’s son was hit by the same illness 24 hours later. That’s an all-too-common occurrence when dealing with norovirus, as the Germantown family and many others in their community recently discovered.

The Valley View Local School District in Montgomery County shut down for two days earlier this month after a suspected norovirus outbreak. Public Health — Dayton & Montgomery County officials confirmed last week that the samples collected were norovirus.

“The Valley View case was a little unusual in terms of the size of the outbreak, but norovirus itself is fairly common,” said Bill Wharton, spokesman for Public Health — Dayton & Montgomery County. “It does peak in the winter months, but it happens year round.”

We talked to three experts in the field to learn more about norovirus.

Facts and background

“Norovirus illness is very common,” said Jeanette St. Pierre, associate director for communication science Division of Viral Disease at the Centers for Disease Control and Prevention. “Each year, norovirus causes 21 million cases of acute gastroenteritis (inflammation of the stomach or intestines or both).”

The season typically lasts from December to April, but norovirus can be contracted any time of the year.

According to the CDC, most outbreaks of norovirus illness happen when infected people spread the virus to others. But, norovirus can also spread by consuming contaminated food or water and touching things that have the virus on them.

Because of its highly contagious nature, outbreaks of norovirus are common in places where people are in close proximity to one another like schools, daycare centers, cruise ships and summer camps.

Nearly two-thirds of all norovirus outbreaks reported in the United States occur in long-term care facilities.

Restaurants, banquet halls and even your own kitchen can be breeding grounds, as norovirus is the leading cause of illness from contaminated food in the United States.

About 50 percent of all outbreaks of food-related illness are caused by norovirus.

This season

“Throughout the norovirus season, there have been cases and outbreaks of norovirus illness throughout the United States,” St. Pierre said.

“Based on the information we have received so far, it does not appear to be an unusual season for norovirus illness. Also, we are not aware of new strains of norovirus that would have caused an increase in cases and outbreaks,” St. Pierre said.

Likewise, according to Wharton, while the recent Valley View school closings brought increased attention to the disease, there have not been an unusually large number of cases reported in the region this season.


“It generally comes on suddenly,” said Dr. Gary Collier, Miami Valley Hospital chief medical officer. “You can feel fine one minute and then feel really bloated, crampy and then nauseated.”

That nausea most often results in vomiting. Other symptoms can include diarrhea, stomach pain, fever, headache and body aches.

“It knocks you down and it knocks you down hard,” Wharton said.

Collier said that most otherwise healthy adults and older children can expect to be sick for about 24-48 hours, but nagging symptoms can last for up to four days.

“You replace the lining of your intestinal tract fairly quickly, but you can still feel bad for three or four days while you are shedding the virus,” Collier said.

Highly contagious

“If you want to break the chain of infection, do frequent hand washing,” Wharton said. “That’s the key to stopping it.”

The close proximity of family members within a household, however, increases the likelihood that others will contract the norovirus.

“It’s almost guaranteed to go through a family,” Collier said. In addition to increased hand washing, Collier suggests washing bedding and all commonly used surfaces, like countertops and doorknobs. Don’t share utensils, dishes or glasses. If someone contracts the norovirus, they should stay home until the illness has run its course — no going to school, work or church.

Worst cases

“It can be a really violent illness,” Collier said. “And for the very young and the very old, it can lead to dehydration.”

Norovirus can be life threatening.

“It contributes to about 70,000 hospitalizations and 800 deaths, mostly among young children and the elderly,” St. Pierre said.

According to the CDC, norovirus can be found in your stool (feces) even before you start feeling sick.

The virus can stay in your stool for two weeks or more after you feel better.

Replace lost fluids

There is no medicine to treat people with norovirus. It cannot be treated with antibiotics because it is viral, not bacterial.

People with the virus, should drink plenty of liquids to replace fluids lost from vomiting and diarrhea. This will help prevent dehydration.

Symptoms of dehydration include decreased urination, a dry mouth and throat, and feeling dizzy when standing up. Children who are dehydrated may also cry with few or no tears and be unusually sleepy or fussy.

Sports drinks and other drinks without caffeine or alcohol can help with mild dehydration. But these drinks may not replace important nutrients and minerals.

Oral rehydration fluids that you can get over the counter are most helpful for mild dehydration.

Even after the nausea and vomiting subside, Collier suggests easing into solid foods starting with things like soup and Jell-O as the intestinal tract will take some time to recover.


According to the CDC, after throwing up or having diarrhea, immediately clean and disinfect contaminated surfaces by using a bleach-based household cleaner as directed on the product label. If no such cleaning product is available, you can use a solution made with 5 tablespoons to 1.5 cups of household bleach per one gallon of water.

And wash your hands frequently with soap and water — after using the toilet, changing diapers and always before eating or preparing food.

Alcohol-based sanitizing products can reduce the number of germs on hands, but they are not a substitute for soap and water.

For additional information on the norovirus, visit

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