LOUISVILLE, Ky. (WDRB) -- Local health officials are raising concerns over what's being called a "quad-demic." 

"It consists of three of our previous enemies we've talked about—RSV, flu and COVID," Dr. Mark Burns, associate professor of Medicine at UofL, said. "This year, there's an additional player. Norovirus. These viruses are the predominant viruses when we talk about respiratory illnesses that are prevalent here in the U.S. for this season."

Norovirus, however, attacks the stomach and gastrointestinal system. Burns said it is highly contagious, and it only takes a small amount of the virus to infect a person. 

Often referred to as the "stomach flu" or "stomach bug," the virus spreads through touching contaminated surfaces, eating contaminated foods, or by touching your eyes, nose or mouth.

It can also spread by coming into direct contact with someone infected with norovirus, sharing food or eating utensils with them, or eating food they made or handled, according to the U.S. Centers for Disease Control and Prevention. 

The most common symptoms of norovirus include vomiting, diarrhea and stomach pain, but other symptoms include fever, headache and body aches. Burns said symptoms last about 48-72 hours, but a person can still be contagious for up to two weeks. 

According to the CDC, a person infected with norovirus can shed billions of virus particles to those around them, and is most contagious when they have symptoms of the virus, especially vomiting, and during the first few days they are feeling better.

The CDC said norovirus can cause dehydration from loss of body fluids because someone infected with the virus can "feel extremely ill" and vomit or have diarrhea multiple times a day. Symptoms of dehydration include decreased urination, dry mouth and throat, feeling dizzy when standing up, crying with few or no tears, and unusual sleepiness or fussiness.

Norovirus is the leading cause of vomiting and diarrhea from acute gastroenteritis among Americans of all ages, with about 2,500 reported outbreaks in the U.S. each year, according to the CDC. Each year, the virus causes an average: 900 deaths—mostly among adults age 65 and older, 109,000 hospitalizations, 465,000 ER visits—mostly in young children, 2,270,000 outpatient clinic visits—mostly in young children, and 19 million to 20 million illnesses.

To protect yourself, doctors suggest washing your hands well and often with soap and water for at least 30 seconds. Hand sanitizer alone does not work well in fighting norovirus, according to the CDC. The agency also suggests cooking shellfish thoroughly, washing fruits and vegetables, clean and disinfect contaminated surfaces, washing laundry in hot water, and staying home when sick for two days after symptoms stop.

To learn more about how norovirus spreads, what symptoms to look for and how to prevent the virus, click here for more information from the CDC.

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