More commonly known as croup, this is an infection of the larynx, trachea, and the bronchial tubes, that occurs mainly in children. It is usually caused by viruses, less often by bacteria. Symptoms include a cough that sounds like a barking seal and a harsh crowing sound during inhaling. Treatment may include moist air, salt water nose drops, decongestants and cough suppressants, pain medication, fluids, and occasionally antibiotics. The major concern in croup is breathing difficulty as the air passages narrow. Close monitoring of the breathing of a child with croup is important, especially at night. While most children recover from croup without hospitalization, some children can develop life-threatening breathing difficulties. Therefore, close contact with the doctor during this illness especially important.