Tracheobronchitis is inflammation of the trachea and bronchi. It is characterised by a cough, fever, and purulent (containing pus) sputum and is therefore suggestive of pneumonia. It is classified as a respiratory tract infection. Tracheobronchitis is often a hospital-acquired infection, particularly in an intensive care setting, associated with the use of mechanical ventilators, and the need for inserting a tracheal tube. In these cases it is known as ventilator-associated tracheobronchitis. The infection begins in the trachea where it colonises and spreads to the bronchi.