Is Croup Contagious?
Lindsay Knake
| 3 min read
Lindsay Knake is a brand journalist and project plan...
Key Takeaways
- Croup is contagious because it is usually caused by common respiratory viruses, including influenza, parainfluenza, RSV and adenovirus. However, not every child exposed to these viruses will develop croup symptoms.
- The hallmark signs of croup are a barking cough, hoarse voice and noisy breathing. Symptoms are most common in children ages 3 months to 3 years and often worsen at night.
- Most cases of croup are mild and can be managed at home, but parents should seek immediate medical care if a child has trouble breathing, develops stridor at rest, struggles to swallow or shows signs of low oxygen, such as blue lips or skin.
A distinct, whistling cough can be a scary thing for a parent to hear in their child.
Croup, an infection caused by respiratory viruses, can lead to a dangerous cough in very young children. The viruses that cause croup are typically very contagious, however, not everyone who is exposed to these viruses develops the symptoms of croup. Here’s more about croup, the causes, symptoms and when to seek medical treatment.
What is croup?
Croup is inflammation of the windpipe, or trachea, and vocal cords, or larynx, according to the National Institutes of Health. Swelling in the upper airways leads to a barking cough, a hoarse voice and noisy, difficult breathing. A child with croup may make a coarse, musical sound when inhaling, which is called stridor. This is common when a child is active or crying, but stridor when the child is at rest can be a sign of more severe croup. Children who have croup are also like to have a fever and may complain of a sore throat.
These symptoms, which are generally worse at night, can be scary for parents and caregivers. Children can wake up gasping and upset, according to the American Academy of Pediatrics (AAP).
Croup usually lasts three to five days, per the AAP. It usually starts like a common cold, and symptoms develop over a day or two. Children from 3 months to 3 years old have the highest risk of croup, and they may have more severe symptoms than older children who get croup.
Is croup contagious?
Croup is typically caused by a respiratory virus such as:
- Influenza
- Parainfluenza
- Respiratory syncytial virus (RSV)
- Measles
- Adenovirus
These viruses are very contagious and most common in fall and winter. Croup can also be caused by allergies or acid reflux, which are not contagious, but this is less common.
About 3% of children in the United States get croup each year and causes about 7% of hospitalizations in children younger than 5, according to the Cleveland Clinic. About 85% of croup cases are mild, while fewer than 1% are severe. Boys are more likely than girls to get croup.
While preventing young children from getting viruses can be very difficult, frequent adult handwashing and keeping children home if they are sick or if there is an outbreak of illness at daycare or school may help reduce the risk of contracting an illness.
How to treat croup
Mild cases of viral croup can generally be treated at home by keeping the child calm, giving them acetaminophen or Motrin for a fever and keeping them hydrated. Cough syrup doesn’t help with croup, per the AAP. There is no research to show cool night air or steam will help improve breathing.
Seek immediate, emergency medical attention if the child:
- Has trouble breathing
- Has a whistling sound with every bread
- Cannot speak or make sounds
- Has stridor when resting
- Has blue lips, skin or nails
- Has extreme difficulty swallowing saliva
Healthcare providers may give a child a breathing treatment with epinephrine or a steroid to reduce swelling.
If your child has persistent or recurrent croup or if you have questions about medication dosing or frequency, talk to your child's primary care provider.
Photo credit: Getty Images
