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Norovirus is not a reportable disease in Oklahoma; however, the Oklahoma State Department of Health investigates outbreaks of norovirus to control the spread of this disease. Noroviruses are a group of viruses that cause diarrhea and vomiting in people. Any human can be infected with norovirus through exposure to stool or vomit of an infected individual. An infected individual can spread the virus from when they become ill to at least three days after symptoms start. Outbreaks have been linked to sick food handlers, contaminated shellfish or water contaminated with sewage. There are many different strains of norovirus and a human can be re-infected with norovirus throughout their lifetime.

Symptoms of noroviruses include nausea, vomiting, diarrhea, and abdominal cramping. In some instances, individuals can also experience a low-grade fever, chills, headache, muscle aches, and may feel tired. The symptoms usually begin about 24 to 48 hours after exposure to the virus, but can appear as early as 12 hours after exposure. The duration of illness is brief with symptoms usually lasting only one or two days.

No specific treatment for norovirus infection is available. Oral rehydration or intravenous fluids may be needed in severe cases. Antibiotics only work against bacterial infections and should not be used for diarrheal illness due to norovirus.

How to prevent norovirus:

  • Wash hands thoroughly before and after preparing food, before eating, after using the bathroom or changing a diapers, after blowing nose, coughing or sneezing, and anytime hands are visibly dirty.
  • People who experience nausea, vomiting or diarrhea should not attend school or work and should not handle food for others while ill.
  • Avoid drinking untreated water.
  • Cook shellfish thoroughly before eating.

Norovirus Fact Sheets and Information:

Norovirus Fact Sheet (43k.pdf) 
  Norovirus Hoja Informativa (84k.pdf)
Safe Water Use During a Boil Advisory (42k.pdf)

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