Oct 12, · Croup is an infection that affects your breathing and causes a distinct “barking” cough. It usually impacts young kids, but in rare cases, adults can develop croup too. Researchers don’t know Author: Julie Marks. Jan 07, · A barking cough is a dry, harsh cough that resembles the sound of a barking seal. This type of cough is most often associated with croup (laryngotracheitis). Croup is usually caused by .