What are middle ear infections?

Middle ear infections are viral or bacterial infections of the middle ear. The middle ear is the area behind the eardrum. Middle ear infections are also called otitis media.

Middle ear infections are viral or bacterial infections of the middle ear space.  This is what most lay people think of as "an ear infection".  The medical name for this is otitis media. Some people erroneously think of ear infections as two types--outer and inner. Actually this "inner ear infection" is  the middle ear.

The middle ear is the space behind the ear drum.  With infection in this space, there is always fluid or pus that keeps the ear drum from moving.  This results in temporarily decreased or lost hearing in the infected ear.  Once the infection and fluid are gone, the ear drum is free to move and transmit sound waves to the inner ear. 
A middle ear infection, known as acute otitis media, is one of the most common childhood infections. Fifty percent of all children will have a middle ear infection by one year of age.

With this infection, the middle ear becomes inflamed. It is caused by bacteria that enter the middle ear through an area called the Eustachian tube. The Eustachian tube connects the middle ear to the back of the nose. A child's Eustachian tube is short, wide, and horizontal. Bacteria can easily travel through this tube to the middle ear.

Congestion from colds or allergies can clog the Eustachian tube. Once the tube is clogged, germs are trapped in the middle ear and cause an infection. The infection makes a fluid called pus. The pus pushes against the eardrum, causing it to become red, sore, and swollen.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.