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Influenza (or flu) is a viral infection of the nose, throat, bronchial tubes and lungs that can make someone of any age ill. Influenza in children may be indistinguishable from disease caused by other respiratory viruses. The common cold, croup, viral pneumonia and undifferentiated acute respiratory disease may be caused by influenza virus. Nausea, vomiting and diarrhea may occur, particularly in children.

What causes influenza?

Influenza virus is an orthomyxovirus. Three virus types are known: influenza A, influenza B and influenza C.

What are the symptoms of influenza?

Abrupt onset of fever, muscle aches, sore throat and nonproductive cough. Young children typically have milder sneezing and coughing

How long is it contagious?

The virus may be found in respiratory secretions for 24 hours prior to the onset of symptoms and up to seven days after the symptoms begin. Influenza is most contagious in the 24 hours before the onset on symptoms.

How can I prevent infection?

  1. Flu vaccine is strongly recommended for any person older than 6 months of age. It is recommended that all child care and preschool providers receive yearly influenza vaccine.
  2. Cover mouth when coughing and sneezing, with tissue if possible. If a tissue is not available, cough or sneeze into your sleeve.
  3. Properly dispose of contaminated tissues.
  4. Clean, rinse with clean water, then sanitize mouthed toys at least daily and when soiled.
  5. Frequent, careful hand washing by child care staff, children and household members.
  6. Avoid aspirin use for children under the age of 18 years of age to prevent Reye’s syndrome.


For more information, please call the Northern Kentucky Health Department at 859.363.2070.

Revised November 2014