Evie is a two year old girl who is brought in by her father with a 2 day history of a barking cough which is worse at night. He noticed she had a runny nose and felt warm to touch yesterday morning but has not been feverish since. On examination her observations are stable, her chest is clear and no sign of intercostal/sternal recession. A barking cough is noted and you feel confident in diagnosing Croup.
Which one of the following statements about Croup is most correct?