Ear Infection Quiz: Test Your Medical IQ

Acute otitis media (ear infection) describes inflammation of the middle ear, or tympanum. During an ear infection there is fluid in the middle ear accompanied by signs or symptoms of ear infection including a bulging eardrum usually accompanied by pain; or a perforated eardrum, often with drainage of pus (purulent material).

Note: A child with a draining ear infection should not swim.

Ear infection is the most frequent diagnosis in sick children in the U.S., especially affecting infants and preschoolers.

Except for wellness baby visits, ear infections are the most common reason for trips to the pediatrician, accounting for approximately 30 million doctor visits a year in the U.S.

Almost all children have one or more bouts of otitis media before age six. Children who have acute otitis media before six months of age tend to have more ear infections later in childhood.

The primary function of the Eustachian tube is to ventilate the middle ear space, ensuring that its pressure remains at near normal ambient air pressure. The secondary function of the Eustachian tube is to drain any accumulated secretions, infection, or debris from the middle ear space. Several small muscles located in the back of the throat and the palate control the opening and closing of the tube. Swallowing and yawning cause contractions of these muscles and help to regulate Eustachian tube function. If it were not for the Eustachian tube, the middle ear cavity would be an isolated air pocket inside the head that would be vulnerable to every change in air pressure, and lead to an unhealthy ear.

Note: A child with an ear infection can travel by airplane, but if the Eustachian tube is not functioning well, changes in air pressure in the plane can cause discomfort.

Bottlefeeding is a risk factor for otitis media in infants. Breastfeeding passes immunity to the child that helps prevent acute otitis media. The position of the breastfeeding child is better than the bottlefeeding position for Eustachian tube function.

If a child needs to be bottlefed, hold the infant instead of allowing the child to lie down with the bottle is best. A child should not take the bottle to bed. In addition to increasing the chance for acute otitis media, falling asleep with milk in the mouth increases the incidence of tooth decay.

An ear infection itself is not contagious. Ear infections are often the result of a previous infection of the throat, mouth, or nose that has relocated and settled in the ears.

Both bacteria and viruses are responsible for middle ear infections. The common cold, a viral upper respiratory infection, is the major cause of ear infections.

A middle ear infection usually occurs after a child has had a sore throat, cold, or upper respiratory infection.

If the upper respiratory infection is bacterial, the infection-causing bacteria may spread to the middle ear. After a viral upper respiratory infection such as a cold, bacteria may move into the middle ear as a secondary infection.

The hallmark of an acute ear infection is sudden, piercing pain in the ear. The pain may be worse when lying down, making it difficult to sleep. Other symptoms include difficulty hearing, fever, fluid drainage from the ears, dizziness, and congestion.

Young children with otitis media may be irritable, fussy, or have problems feeding or sleeping. Older children may complain about pain and fullness in the ear (earache). Fever may be present in a child of any age. These symptoms are often associated with signs of upper respiratory infection such as a runny or stuffy nose, or a cough.

Temporary hearing loss may occur during an ear infection because the buildup of pus within the middle ear causes pain, and dampens the vibrations of the eardrum.

Untreated ear infections can lead to more serious complications, including mastoiditis (a rare inflammation of a bone adjacent to the ear), hearing loss, scarring and/or perforation of the eardrum, meningitis, speech and language development problems, facial nerve paralysis, and possibly -- in adults -- Meniere's disease.

Note: Meniere's disease is likely a disorder of the flow of fluids of the inner with symptoms that include vertigo, tinnitus, and hearing loss.

Remember that the common cold is a key cause of ear infections. Because of the highly contagious nature of the common cold, one strategy for prevention of the cold itself and subsequent ear infections is to keep cold viruses at bay. The most effective way to do this is frequent and meticulous hand washing.

Other strategies to prevent acute ear infections are to ensure a child is vaccinated. Ensuring that a child receives an annual flu vaccine and is up to date with his/her pneumococcal vaccine are excellent strategies used to prevent the most common causes of ear infections.

Other lines of defense against ear infections include avoiding secondhand smoke and breastfeeding your baby for the first year of life.