Norovirus Update

Karen Swecker, RN, MedFlight Infection Control Liaison

Norovirus is a highly contagious infection that can be transmitted via an infected person, contaminated food or water and contaminated surfaces.  Approximately 20 million people are infected with norovirus each year resulting in 70,000 hospitalizations and 800 deaths.  Norovirus is the leading cause of foodborne illness in the US.

A person infected with Norovirus can shed billions of viral particles; however, it only takes around 18 viral particles to cause an infection.   An infected person can spread the disease beginning a few days before symptoms appeal, and continue to be infectious as the virus remains in the stool for 2 weeks or longer.

The symptoms of norovirus appear suddenly and include watery diarrhea, acute onset of nausea and vomiting, abdominal pain and may be accompanied with a fever, headache and body aches.  Symptoms typically appear within 12 to 48 hours after exposure and last 1 to 3 days.

There isn’t a vaccine for Norovirus, prevention relies on:

  • Thorough hand washing with soap and water – recommended over alcohol hand gel
  • Wash fruits and vegetables before preparing and eating
  • Cook shellfish thoroughly – Norovirus can survive temperatures up to 140o F
  • Keep the sick away from food preparation areas
  • If you are sick do not prepare food for others
  • If you are sick do not provide patient care
  • Clean surfaces with a bleach solution (1/3 cup bleach per gallon of water or 1TBSP +1/2 tsp per 32 ounces of water in a spray bottle) immediately after vomiting or having diarrhea. Surfaces should remain wet for 10 minutes to fully kill any pathogens.
    • IMPORTANT: wipe down surfaces with clean water after bleach disinfection
  • Close the toilet lid before flushing – flushing can aerosolize viral particles
  • Handle dirty laundry carefully wearing gloves – disinfect hands and reusable gloves after use

More information may be found at: