Otitis is a general term for infection or inflammation of the ear.
Ear infection; Infection - ear
Otitis can affect the inner or outer parts of the ear. The condition is classified according to whether it occurs suddenly and for a short time (acute) or repeatedly over a long period of time (chronic).
Otitis externa (swimmer's ear). Involves the outer ear and ear canal. A more severe form can spread into the bones and cartilage around the ear.
Otitis media (ear infection). Involves the middle ear, which is located just behind the eardrum.
Acute ear infection. Starts suddenly and lasts for a short period of time. It is often painful.
Chronic ear infection. Occurs when the ear infection does not go away or keeps coming back. It may cause long-term damage to the ear.
Otitis media with effusion. Occurs when there is thick or sticky fluid behind the eardrum in the middle ear, but there is no ear infection.
Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.