Croup is a condition caused by an infection that affects the upper portion of the airway, including the larynx (voice box) and trachea (windpipe). It’s common in young children between ages 6 months and 3 years. It tends to occur in the fall months.

Common symptoms of croup include:

  • barking cough
  • high-pitched or noisy breathing (stridor)
  • Losing your voice is a hoarseness.
  • low grade illness
  • A nose that is not normal.

The symptoms of croup can be worse in the evening or when a child is crying. They last for 3 to 5 days, but a mild cough can last for up to a week. If your child has trouble breathing, seek medical attention.

The infection that causes croup is contagious. But how contagious is it to adults? Is it more contagious between children? Read on to find out.

Croup is most often caused by a viral infection, typically by a type of virus called a parainfluenza virus. Other viruses that can cause it include:

  • enteroviruses are related to the enteroviruses.
  • The rhinoviruses are related to the ones that cause the flu.
  • The A and B viruses are related to the flu.
  • Respiratory syncytial virus is a respiratory disease.

In rare cases, bacteria can cause croup. This type of croup is often more severe than viral types.

The disease that causes croup can be transmitted from person to person. The respiratory droplets that are produced when someone coughs or sneezes are the transferrable agents.

It is possible to spread an infectious disease if you come into contact with contaminated surfaces, such as doorknobs or faucet handles, and then touch the face, nose, or mouth.

Teenagers sometimes develop croup, but it’s very rare in adults. Adult airways are larger and more developed than those of children. As a result, they might come into contact with the virus and possibly develop an infection, but it will not cause the same breathing issues that it does in children.

If an adult develops a sore throat or a light cough, they are usually mild. Some adults may need to be hospitalized for more severe breathing symptoms. This is very rare.

As of 2017, there were only 15 reported cases of adult croup in medical literature, though the true incidence is not known. Read more about croup in adults.

Infectious agents that cause croup can be transferred for about 3 days after a person starts to show symptoms or until their fever disappears. The recommendation is to remain home until 24 hours without fever and without using fever-reducing medications.

If your child has a disease, it is best to keep them home from school for at least 3 days. You should keep them home if they have a disease.

If you wash your hands often, especially after sneezing, you can reduce your risk of developing a disease called croup. If you see someone with a disease, try to keep your distance.

It is helpful to cough or sneeze into a tissue if you or your child have already been diagnosed with croup. It is a good idea to wash your hands frequently.

There are also vaccines available for some bacterial infections that cause illnesses similar to severe croup. These include the Haemophilus influenzae type b (Hib) vaccine and the diphtheria vaccine. Only certain adults at high risk will qualify for the Hib vaccine.

Speak with your doctor or your child’s pediatrician to determine if and when these vaccines are needed.

Making sure that both you and your child receive these vaccines can protect against these more serious infections. Be sure to follow the routine vaccine schedules for adults and for children.

Croup affects children only. Most cases are caused by a virus.

The virus is not as harmful to adults as it is to children. Adult airways are less susceptible to airway issues.

It is best to keep children at home for at least 3 days until they have abated from croup.