Norovirus spreading again in valley

Norovirus, a nasty illness causing vomiting and diarrhea, has sickened people in the Flathead Valley and across Montana, triggering a warning Friday from health officials.

A press release urged people to practice good hand and food-handling hygiene and to stay home if they are ill to slow the spread of this highly contagious virus.

County Public Health Officer Joe Russell said his department began looking into a possible outbreak several weeks ago.

“We had 15 people attending a function come down ill,” he said.

Russell said the department investigated the cases that began after a gathering at a restaurant but determined food was not responsible. He said the bug may have spread from something like a virus-contaminated utensil that many people handled.

Narrowing down the suspect disease was simple.

“We find noro one way — symptoms,” Russell said. “You generally don’t get a fever. You get vomiting and diarrhea. These together form a red flag.”

Symptoms develop suddenly then spread easily in households or group settings. Not considered a serious disease, norovirus usually lasts from one to three days.

“It’s self-limiting but people get extremely sick,” Russell said. “I’ve had people say, ‘This was the worst two days I’ve had in a long time.’”

The virus can pose a serious threat to the elderly, very young or people with weak immune systems. Russell said they may become dehydrated, leading to serious complications including death.

Russell said the norovirus has been circulating in the Flathead Valley for years. He recalled a widespread outbreak about 14 years ago.

“Noro is just endemic,” Russell said. “It never leaves a community.”

In earlier years, the virus was called Norwalk then Norwalk-type virus until it was deemed norovirus. Like cold or rhinoviruses, norovirus actually refers to a group of viruses that cause gastroenteritis. It’s called stomach flu by some people but it has no relationship to influenza.

It became notorious when incidents of wide-spread illness were covered by national news media.

“This is cruise-ship disease,” Russell said. “It takes just one person strategically located to make a whole lot of people sick.”

Because norovirus spreads so easily, he said the health department reacts quickly to reports of illness associated with a food purveyor. They ask people who got sick about what they ate and what they didn’t eat when they became ill to determine if it’s related to a particular food.

Nationwide, many norovirus outbreaks have been traced to food handled by one infected person.

Russell said his inspectors make sure restaurants understand that people who have been ill must not handle any food and that they must strictly follow all health regulations.

“We try to be preventative,” he said.

According to a Centers for Disease Control fact sheet, even people at home who have been ill should not handle food for at least three days after their symptoms disappear. Russell and the CDC site said people may remain contagious for as long as two weeks after they recover.

People don’t develop long-lasting immunity because of the many different strains of norovirus.

“It’s a pretty robust virus,” Russell said.

To most effectively kill the virus on nonporous surfaces, wipe with a solution of one-third cup of bleach to a gallon of water. This virus is less susceptible to alcohol and detergents.

There is no vaccine to prevent norovirus infections. Antibiotics have no effect on norovirus.

Health officials say people with symptoms of nausea, vomiting and diarrhea should drink plenty of fluids, stay home, wash hands often and not prepare food for others for at least three days after recovery.

Russell said that the norovirus may actively spread in a community for weeks or months. He recalled a bad outbreak in Butte a few years ago that swept through nursing homes and persisted for months.

He urged people to follow all the recommendations, particularly washing hands often. 

“All it takes is one person with good hygiene practices to start to stop the disease,” he said. “If everyone does this, it acts like a vaccine by limiting transmission.”

Beyond the Flathead, norovirus cases have been confirmed in Cascade, Chouteau, Lewis & Clark, Park, Roosevelt, Teton, Valley and Yellowstone counties.

Reporter Candace Chase may be reached at 758-4436 or by e-mail at cchase@dailyinterlake.com.