Norovirus (Norwalk-like Viruses)
Prevention and Control of Communicable Diseases
Norovirus (Norwalk-like Viruses)
(Norwalk-like Viruses)
Noroviruses cause gastroenteritis, an inflammation of the stomach and small and large intestines. Norovirus is often incorrectly called the “stomach flu”, although it is not caused by the influenza virus.
Cause
Norovirus (previously known as calicivirus, Norwalk virus, or Norwalk-like virus).
Symptoms
Watery diarrhea and vomiting. In addition, fever, headache, muscle aches, fatigue, and stomach cramps can occur. The illness can be mild to moderately severe with symptoms usually lasting 24 to 72 hours.
Spread
The viruses leave the body through the feces of an infected person and enter another person when hands, food, or objects (such as toys) contaminated with feces are placed in the mouth. Spread can occur when people do not wash their hands after using the toilet or changing diapers. People can also get sick by eating food items contaminated during preparation or serving. Aerosolized spread from vomiting is possible. Person-to-person spread often occurs within families, schools, nursing homes, cruise ships, in child care settings, and communities.
Incubation
It takes 10 to 50 hours, usually from 12 to 48 hours, from the time a person is exposed until symptoms develop.
Contagious Period
Individuals are most contagious while the symptoms are present; generally the first 72 hours after onset. Prolonged shedding can occur up to 3 weeks.
Exclusion
Child Care and School: Until the child has been free of diarrhea and vomiting for at least 24 hours.
No one with vomiting and/or diarrhea should use pools, swimming beaches, recreational water parks, spas, or hot tubs for 2 weeks after diarrhea and/or vomiting symptoms have stopped.
Staff must avoid food preparation when diarrhea and vomiting are present and for at least 3 days after diarrhea and/or vomiting have stopped. Please call your local health department to see if these restrictions apply.
Diagnosis
Recommend parents/guardians call their healthcare provider if their child has symptoms to discuss whether laboratory tests need to be done to determine the cause.
Treatment
Vomiting and diarrhea may lead to dehydration, which may be a medical emergency. Ask a healthcare provider how to prevent dehydration.
Prevention/Control
- Regular and thorough handwashing is the best way to prevent the spread of communicable diseases. Wash hands thoroughly with soap and warm running water after using the toilet and changing diapers and before preparing or eating food. Staff should closely monitor or assist all children, as appropriate, with handwashing after children have used the bathroom or been diapered.
- Restrict students from sharing any communal food items that are brought from home. In the classroom, children should not serve themselves food items that are not individually wrapped. The teacher should hand out these items after washing his/her hands. (This is not intended to discourage family-style serving in the absence of an outbreak.)
- Clean and disinfect diapering area and potty chairs after each use and bathroom toilets, sinks, and toys at least daily and when soiled.
- Clean and sanitize mouthed objects and surfaces at least daily and when soiled.
For more information, call the Missouri Department of Health and Senior Services (MDHSS) Bureau of Communicable Disease Control and Prevention at 573-751-6113 or 800-392-0272 (24/7), or call your local health department.
Norovirus Parent Fact Sheet
Your child may have been exposed to:
Norovirus
Norovirus is a viral infection of the stomach and intestines.
If you think your child has Norovirus:
- Tell your child care provider.
- Need to stay home?
- Child Care and School:
Yes, until the child has been free of diarrhea and vomiting for at least 24 hours.
- Child Care and School:
In addition, anyone with vomiting and/or diarrhea should NOT use pools, swimming beaches, recreational water parks, spas, or hot tubs for at least 2 weeks after diarrhea and/or vomiting have stopped.
Symptoms
Your child may have watery diarrhea, vomiting, and fever. Other symptoms may include headache, stomach cramps, and tiredness. Illness usually lasts for 24 to 72 hours.
If your child is infected, it may take 1 to 2 days for symptoms to start.
Spread
- By eating or drinking contaminated food or beverages.
- By touching contaminated hands, surfaces, or objects.
- Also when someone vomits and bacteria get in the air. Norovirus is easily spread in the household.
Contagious Period
The illness can spread as long as the virus is in the feces.
Call your Healthcare Provider
- No specific treatment is available.
- Ask how to prevent dehydration. Your child may become dehydrated due to vomiting or diarrhea.
Prevention
- Wash hands after using the toilet and changing diapers and before preparing food or eating. Your child may need help with handwashing.
- Clean and disinfect any objects that come in contact with feces. This includes toilets (potty chairs), sinks, toys, and diaper changing areas. Use a product that kills viruses.
For more information, call the Missouri Department of Health and Senior Services (MDHSS) Bureau of Communicable Disease Control and Prevention at 573-751-6113 or 800-392-0272 (24/7), or call your local health department.