What is croup?

Croup is a very common respiratory problem. It is a swelling of the airway at the voice box (larynx) and windpipe (trachea) usually caused by a virus. The same virus that causes croup can cause other respiratory diseases like bronchitis, bronchiolitis and pneumonia. Croup is characterized by a harsh barking cough that can be scary for children and caregivers.

Who gets it and when?

Croup is most common in children under 3 years of age. Some children get croup as often as they have a respiratory illness. It can occur at any time of the year, but is most common between October and March.

What are the symptoms?

When a child has croup, the airway just below the vocal cords becomes narrow. This makes breathing noisy and difficult. Usually a child with croup has a low fever. Because the voice box contains the vocal cords, the main symptom of croup is a harsh cough that sounds like a seal barking, following a runny nose, cough and hoarseness. Croup usually gets worse at night with a crowing sound while breathing. Croup may last one to seven days. Croup is usually managed by moisturizing the air.

How is it spread?

The germs which cause croup are spread from person to person by contact with respiratory secretions (sneezing, coughing, saliva). Croup is about as contagious as the common cold. Children with croup or other respiratory infections should not have frequent contacts with infants less than six months of age.

Should the child stay home?

There is no reason to exclude the child from child care simply because of their harsh cough. However, you can separate the child from other children in the program if (1) a specified cause is identified that requires exclusion, or (2) the child is not well enough to participate in usual activities, or (3) the illness results in a greater need for care than can be provided by the staff without compromising the health and safety of other children.

When should the child be sent home and seen by a health care provider?

A child who rapidly develops a crowing sound when breathing in and out (while at rest) needs to be seen by a health provider. This child may appear very sick, with a high fever, drooling, and a preference for sitting up. These symptoms are due to blocked air passages.

What can be done to limit the spread?

To prevent the spread of infection, follow routine healthy practices:

  • Handwashing is the most important infection control measure. Make sure that all children and staff use good handwashing practices, especially after wiping or blowing noses; after contact with any nose, throat or eye secretions; before preparing or eating food; after toileting.
  • Clean and disinfect all mouthed toys and frequently used surfaces on a daily basis.
  • Make sure that the facility is well ventilated, and that children are not crowded together, especially during naps on floor mats or cots. Open the windows and have the children play outside as much as possible, even in the winter.
  • Teach children to cough and sneeze into their elbow, wipe noses using disposable tissues, throw the tissue into the wastebasket, and wash their hands.


Infection Control in the Child Care Center and Preschool, Leigh G. Donowitz, Third Edition, 1996.

Red Book: Report of the Committee on Infectious Diseases 25th Edition, American Academy of Pediatrics (AAP), 2000.

Pediatric hospitalizations for croup (laryngotracheobronchitis): Biennial increases associated with human parainfluenza virus 1 epidemics. Marx A, Torok TJ, Holman RC, Clarke MJ, Anderson L1.

California Childcare Health Program
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