RSV and flu bought off to “early and brisk” begins this winter season, Dr. William Schaffner, professor of infectious ailments at Vanderbilt College Medical Middle in Nashville, Tenn., tells Fortune. “Now we’re having different winter viruses—together with norovirus, a dominantly intestinal virus—additionally spreading this season.”

Instances of norovirus are rising in numerous areas of the U.S. and world, together with Europe and Canada, and the pathogen is making headlines. The virus lately sickened almost 500 on two U.S.-based cruise ships and is as soon as once more liable for myriad faculty closings, with one Detroit-area principal detailing a “rolling incidence of scholars throwing up” on a latest faculty day, inflicting the cancelation of courses from Feb. 9 via Valentine’s Day.

Whereas the virus is apt to surge in winter, this 12 months’s season is especially sturdy thus far, specialists inform Fortune.

Here’s what it’s worthwhile to know to maintain secure from the frequent wintertime menace recognized for sickening entire households directly.

What’s norovirus and the way does it unfold?

Norovirus, typically mistaken for the abdomen flu, “spreads with outstanding ease,” Schaffner tells Fortune. Its nicknames embrace “winter vomiting illness” and “the cruise ship virus,” because it simply spreads amongst these in shut quarters, he provides.

The sickness often spreads from individual to individual, by way of “fecal-oral” transmission. You possibly can catch it by consuming contaminated meals or water, or by touching a contaminated floor, then touching your mouth. 

It takes a really low stage of virus to get sick—so small that even a microscope can’t detect it. As a result of it’s primarily handed via particles of feces invisible to the bare eye, it’s simple to unknowingly unfold and contract the illness—if, for instance, you don’t wash your palms properly after utilizing the restroom or altering a child’s diaper. “It doesn’t take quite a bit to get individuals fairly sick,” Dr. Georges Benjamin, head of the American Public Well being Affiliation, tells Fortune. “That’s the principle cause it’s so infectious.”

What’s extra, in the event you’re close to somebody who’s projectile vomiting, “you may really be contaminated by way of aerosols,” Schaffner provides.

What are the signs of norovirus?

Frequent signs embrace:

• Diarrhea
• Vomiting
• Nausea
• Abdomen ache

Signs happen in reference to gastroenteritis, or irritation of the abdomen or intestines, based on the U.S. Facilities for Illness Management and Prevention. Different signs could embrace fever, headache, and physique aches.

Signs often happen inside 12 to 48 hours of publicity, and final for one to a few days, based on the CDC. As a result of norovirus may cause repeated vomiting and diarrhea, “the largest danger is getting very dehydrated,” Benjamin advises—particularly among the many younger, aged, and people with different medical situations.

Why is norovirus circulating proper now?

Norovirus is a standard winter-time virus, although it’s additionally recognized to flow into by way of gatherings throughout different occasions of the 12 months, like at spring or summer season weddings and cruise-ship journeys. 

Sometimes, nonetheless, norovirus is seen November via March, Dr. Ali Alhassani, head of scientific at Summer season Well being and a pediatrician at Boston’s Kids’s Hospital, instructed Fortune.

“We’re beginning to see just a little bit greater exercise than typical, and just a little bit on the early facet, too,” Alhassani says, including that the virus is on the uptick and maybe approaching a peak within the U.S.

Summer season Well being, a subscription-based pediatrics service accessible by way of textual content message, has seen a 13% improve in visits for “abdomen bug” signs prior to now two months, he provides: “We’re undoubtedly seeing that as an enormous sample in children throughout the U.S.”

Pathogens like flu, RSV, and norovirus could be anticipated extra regularly now that pandemic restrictions have been universally lifted, specialists say. 

“We’re going to see an increasing number of infectious ailments which are handed on, significantly in giant teams, and norovirus is an instance of that,” Benjamin says. “Bear in mind, we’re principally going from nearly no instances of something [during COVID lockdowns] to a bunch of instances of one thing,” be it RSV or flu earlier this 12 months, or norovirus now.

“We’re out and about sharing germs with one another once more.”

How will you finest defend your self and your loved ones from norovirus?

One of the best recommendation, specialists instructed Fortune: Wash your palms regularly and keep away from others who’re sick.

Dr. Alice Pong, scientific medical director of infectious ailments at Rady Kids’s Hospital-San Diego, advises adults to be further diligent about washing their palms earlier than they eat—and to have their children do the identical. Elevated warning is warranted as a result of norovirus could be transmitted by way of doorknobs, buying carts, mild switches, and different frequent surfaces.

Alcohol-based hand sanitizers don’t work properly on some viruses, together with norovirus. So ditch the hand sanitizer in favor of truly washing your palms, she advises.

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