Norovirus Cases on the Rise, New Highly Contagious Australian Strain in U.S. - How Can You Prevent It?

Although the flu is on everyone’s minds this season, the winter vomiting bug, or the norovirus, is making its rounds.

The U.S. Centers for Disease Control and Prevention (CDC) reports that the norovirus causes about 70,000 hospitalizations and 800 deaths each year, mostly in young children and the elderly.

Some of the virus' common symptoms include nausea, vomiting, diarrhea and stomach pains. The CDC points out that the norovirus is often referred to as the stomach flu, but it is unrelated to influenza.

Last year around this time, a norvirus outbreak hit Iowa, spreading to several Iowa counties including waves of the disease hitting Polk County.

In Eastern Iowa, the Johnson County Health Department even investigated a nearby pool facility in Eastern Iowa, where several people contracted the disease, but were unable to disclose the name of the facility due to state law, according to an investigative report by Erin Jordan of the Gazette.

KCCI reports that Norovirus infections are up this year in Iowa, partially due to this new strain:

A new strain of the norovirus is quickly spreading this flu season in Iowa and across the U.S.

"There are different strains that go around every year and according to the CDC in years when there is a new strain we can see higher numbers for norovirus," said Sarah Boese with the Polk County Health Department.

A new norovirus strain, GII.4 Sydney, was detected last year in Australia.  The strain hit the U.K. and sickened over a million people. It has now reached the United States and this new strain appears to be taking over.

Of norovirus cases reported from September to December, 54 percent have been identified as GII.4 Sydney, according to recently released data.

The first norovirus outbreak was reported in Ohio in 1968. Today, approximately 21 million illnesses are attributable to norovirus in the U.S. each year, reports the CDC.  Of those, approximately 25 percent can be attributed to foodborne transmissions. The norovirus can also spread quickly in closed places like daycare centers, nursing homes, schools, and cruise ships.

This hardy virus is extremely contagious. The BBC reports that norovirus is one of the few infections you can catch from a toilet seat. The virus can survive temperatures as high as 140°F, which makes eating raw fish, such as oysters, particularly dangerous.

Noroviruses can live in vomit or stool even before a person experiences symptoms, and up to two weeks after symptoms disappear. People are most contagious when they experience symptoms and during the first three days after recovery, reports the CDC.  

There is no treatment or vaccine against norovirus. To help prevent contamination, the CDC recommends the following tips:

5 Tips to Prevent Norovirus From Spreading

1. Practice proper hand hygiene

Always wash your hands carefully with soap and water:

• after using the toilet and changing diapers, and
• 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.

2. Wash fruits and vegetables and cook seafood thoroughly

• Carefully wash fruits and vegetables before preparing and eating them.
• Cook oysters and other shellfish thoroughly before eating them.
• Be aware that noroviruses are relatively resistant. They can survive temperatures as high as 140°F and quick steaming processes that are often used for cooking shellfish. Food that might be contaminated with norovirus should be thrown out.
• Keep sick infants and children out of areas where food is being handled and prepared.

3. When you are sick, do not prepare food or care for others

• You should not prepare food for others or provide healthcare while you are sick and for at least 2 to 3 days after you recover.
• This also applies to sick workers in schools, daycares, and other places where they may expose people to norovirus.

4. Clean and disinfect contaminated surfaces

• After throwing up or having diarrhea, immediately clean and disinfect contaminated surfaces.
• Use a chlorine bleach solution with a concentration of 1000–5000 ppm (5–25 tablespoons of household bleach [5.25%] per gallon of water) or other disinfectant registered as effective against norovirus by the Environmental Protection Agency (EPA).

5. Wash laundry thoroughly

Immediately remove and wash clothes or linens that may be contaminated with
vomit or stool (feces).

You should—

• handle soiled items carefully without agitating them,
• wear rubber or disposable gloves while handling soiled items and wash your hands after,
• and wash the items with detergent