Acute respiratory infections (ARIs) are classified as upper respiratory tract infections (URIs)
or lower respiratory tract infections (LRIs). The upper respiratory tract consists of the airways
from the nostrils to the vocal cords in the larynx, including the paranasal sinuses and the
middle ear. The lower respiratory tract covers the continuation of the airways from the
trachea and bronchi to the bronchioles and the alveoli. ARIs are not confined to the
respiratory tract and have systemic effects because of possible extension of infection or …