It's normally not deadly, but people who catch the virus sometimes think they're dying.
It's the dreaded norovirus -- most of us know it as the "stomach virus" -- and North Carolina health officials say it's thriving and wreaking some havoc in the Charlotte area.
The N.C. Division of Public Health issued an alert Tuesday, saying it had received reports of multiple outbreaks from eight of the state's 100 counties. Included in the list were Mecklenburg, Cabarrus and Catawba counties in the Charlotte area.
"The best course of action is prevention," said Dr. Megan Davies, the state's epidemiologist.
She said there are no specific medications to treat the virus' symptoms -- vomiting, diarrhea and stomach cramps.
The virus strikes suddenly, with victims feeling fine and then becoming quite ill within a few hours. Davies said fever, chills, headache, muscle ache and general sense of tiredness also can accompany the virus.
She said most victims recover in a day or two, but the norovirus can be dangerous for younger children and the elderly. The biggest problem is dehydration, as victims cannot eat and lose fluids.
"The most important message we have right now is that people who are ill with vomiting or diarrhea should not work, go to school, or attend daycare while they are having symptoms," Davies said.
"Everyone needs to wash their hands frequently and thoroughly with soap and water," she added.
Davies said hand sanitizers are not as effective as soap and hot water in dealing with the virus.
Dr. David Weber, an infections disease specialist at UNC-Chapel Hill, told WRAL in Raleigh that the virus can be contracted by touching a contaminated surface or eating food prepared by someone who's sick. Dozens of people came who ate Jan. 13 at a Catawba County restaurant later contracted norovirus, state health officials say.
Here are questions and answers about dealing with norovirus:
Q. When is a person contagious?
A. From the moment they start coming down with the illness, until at least three days after recovery (and sometimes a day or two longer).
Q. How long does the illness last?
A. Usually one or two days.
Q. How can it be prevented?
A. By washing your hands with soap and water frequently. People who have the virus should not go to school, work or daycare. And people who are sick should not prepare food for others.
Q. How can the virus be killed?
A. Norovirus is difficult to kill. The best way to treat contaminated surfaces (surfaces or clothing contaminated with vomit or stool) is with a diluted bleach solution (1 part bleach to 10 parts water), or a bleach-based household cleaner.
Q. When is the virus typically seen?
A. From October to March. It is a hardy virus that can live for days on contaminated surfaces.
Q. When should a doctor be called?
A. There is no effective treatment of the virus. But younger children and the elderly might need medical treatment, because dehydration can happen rapidly.
Q. As of this week, where is the virus being reported?
A. Reports are coming from across the state, but outbreaks have been reported in Mecklenburg, Cabarrus and Catawba counties in the Charlotte area; and in Alamance, Pitt, Orange, Stokes and Wake counties.