Norovirus infection

Norovirus infection can cause the sudden onset of severe vomiting and diarrhea. The virus is highly contagious and commonly spread through food or water that is contaminated by fecal matter during preparation. You can also be infected through close contact with an infected person.

Diarrhea, abdominal pain and vomiting typically begin 24 to 48 hours after exposure. Norovirus symptoms last one to three days, and most people recover completely without treatment. However, for some people — especially infants, older adults and people with underlying disease — vomiting and diarrhea can be severely dehydrating and require medical attention.

Norovirus infection occurs most frequently in closed and crowded environments such as hospitals, nursing homes, schools and cruise ships.

Symptoms Causes Risk factors Complications Prevention

Signs and symptoms of norovirus infection include:

  • Nausea
  • Vomiting
  • Abdominal pain or cramps
  • Watery or loose diarrhea
  • Malaise
  • Low-grade fever
  • Muscle pain

Signs and symptoms usually begin 24 to 48 hours after first exposure to the virus, and last one to three days. You may continue to shed virus in your feces for up to three days after recovery.

Some people with norovirus infection may show no signs or symptoms. However, they are still contagious and can spread the virus to others.

When to see a doctor

Seek medical attention if you develop diarrhea that doesn't go away within several days. Also call your doctor if you experience severe vomiting, bloody stools, abdominal pain or dehydration.

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