Laryngitis (infection of the voice box or larynx) Click on the
name of the infection in the image above to find out more about
the symptoms, diagnosis and treatment of these respiratory tract
infections. What is laryngitis? Laryngitis is an infection of
your larynx, which results in a hoarse voice and difficulty
speaking. Your larynx is at the top of your trachea (windpipe)
at the front of your throat, and contains your vocal cords. The
vocal cords vibrate and make sound when air passes through them.
This is how you speak. An infection of your larynx causes your
vocal cords to become inflamed so that they cannot vibrate
properly, which in turn affects your voice. The larynx also has
two other important functions: it helps air move into your
trachea when you breathe, and together with the epiglottis
(which sits at the top of the larynx), helps to prevent anything
other than air from going down your trachea when you swallow.