What are middle ear infections?

Fluid or pus: ... In the middle ear. The middle ear is the space behind the eardrum seen when looking in the ear canal. They are very common in young children but less common after 4 or 5 years of age. They usually respond to antibiotics but the middle ear fliud may take several weeks to resolve even after the infection is treated. Ear tubes are placed for chronic infections that don't clear up.

Infection: An infection of the middle ear. That is, behind the ear drum.

Canal/middle/nerve: Middle ear infections affect the cave like enclosure located behind the ear drum & includes an air gap, the ear bones, walls & a drain to the throat (eustachian tube= et). The walls create mucous that should drain into the et. If the et is blocked during a cold or allergies, the mucous can build up & stray throat germs get in & feast on the mucous causing infection.