Final answer:
Croup is a viral inflammation of the larynx and the trachea that causes edema and spasm of the vocal cords, primarily affecting children. Symptoms include a barking cough, hoarseness, difficulty breathing, and a high-pitched sound when inhaling.
Step-by-step explanation:
The viral inflammation of the larynx and the trachea that causes edema and spasm of the vocal cords is called croup. Croup is usually caused by a viral infection, most commonly by the parainfluenza virus. It primarily affects children, especially those between the ages of six months and three years. The characteristic symptoms of croup include a barking cough, hoarseness, difficulty breathing, and a harsh high-pitched sound when inhaling (called stridor).