What is a middle ear infection? A middle ear infection, also called otitis media, is a common, often painful, type of ear infection that occurs behind the eardrum. Middle ear infections are caused by bacteria or viruses. A middle ear infection can interfere with the normal process of hearing and result in ear pain, hearing impairment, and other symptoms. People of all ages can get a middle ear infection, but it is more common in infants and young children up until the age of three. Your ear is divided into three sections: the outer ear (includes the ear and ear canal), the middle ear (includes the eardrum and three tiny bones called ossicles), and the inner ear. Hearing occurs when sound waves travel through the outer ear and into the middle ear, where they cause vibration of the eardrum and ossicles. These vibrations are then transmitted through the inner ear, converted into electrical impulses, and translated by the brain as sound. The Eustachian tubes are responsible for equalizing air pressure in the middle ear and allowing mucus to drain from the middle ear to the throat. Sometimes, however, the tube can become blocked by congestion, which causes fluid from the middle ear to build up. Bacteria or viruses can enter the middle ear through the Eustachian tubes, leading to an ear infection. There are two types of middle ear infections: Acute otitis media usually follows a viral upper respiratory tract infection, such as a cold or flu. Chronic otitis media is an ongoing middle ear infection that can occur after acute otitis media or because of a poorly healed ruptured eardrum. Treatment for a middle ear infection varies depending on the specific type of infection. Treatment may include oral medications, ear drops, or surgical procedures in severe cases. Complications of a middle ear infection can be serious in some cases and result in permanent hearing loss, brain abscess, meningitis, and other problems. Seek prompt medical care if you, or your child, have symptoms of a middle ear infection, such as ear pain and drainage, or if a middle ear infection is not getting better. Seek immediate medical care (call 911) if you or your child, someone you are with, develops seizures, lethargy, or a change in alertness.