An infection of the middle ear, the air-filled space behind the eardrum that contains the tiny vibrating bones of the ear.
Ear infections are common inflammatory conditions affecting the ear, often caused by bacteria or viruses. They can occur in the outer, middle, or (less commonly) inner ear, with middle-ear infections being especially frequent in young children. Depending on the location and severity, ear infections can range from mildly uncomfortable to significantly painful.
What Is an Ear Infection?
An ear infection develops when fluid builds up and becomes infected within part of the ear. The most common type—acute otitis media—occurs in the middle ear, the space behind the eardrum. Other types include:
- Otitis externa (outer ear infection), often called “swimmer’s ear”
- Inner ear infections, which are less common and typically involve balance problems rather than pain
How Ear Infections Develop
Ear infections often follow respiratory illnesses such as colds or sinus infections. When the air-filled space behind the eardrum cannot drain properly, fluid can accumulate, creating an ideal environment for germs to grow. Several factors may contribute:
Bacterial or Viral Infection
Inflammation caused by viruses (such as those causing colds) or bacteria can lead to trapped fluid and infection in the middle ear.
Eustachian Tube Dysfunction
Children are especially vulnerable because their eustachian tubes—tiny passages that help equalize pressure and drain fluid—are shorter, narrower, and more easily blocked.
Upper Respiratory Illness
Congestion, allergies, or sinus swelling can obstruct the tubes and increase the risk of infection.
Environmental Factors
- Secondhand smoke
- Bottle-feeding while lying down
- Seasonal allergies
- Frequent exposure to other children (daycare settings)
Common Symptoms of an Ear Infection
Symptoms vary depending on age and the part of the ear affected. Typical signs include:
- Ear Pain Sharp, throbbing, or constant discomfort is often the first sign, especially in middle-ear infections.
- Hearing Difficulties Sounds may seem muffled due to fluid behind the eardrum.
- Fever Mild to moderate fever may accompany the infection.
- Irritability in Children Babies and toddlers may pull at their ears, cry more, or struggle to sleep.
- Fluid Drainage In some cases, yellow or cloudy fluid may leak from the ear if the eardrum ruptures.
- Fullness or Pressure in the Ear A sensation of blockage or pressure is common.
- Balance Issues Inner ear involvement can lead to dizziness or unsteadiness.
When to Seek Medical Care
Most mild infections improve on their own, but medical evaluation is important when symptoms are severe, persistent, or accompanied by high fever. A healthcare provider may recommend pain relief, monitoring, or antibiotics depending on the cause and age of the patient. Prompt treatment helps prevent complications such as chronic infections or hearing problems.
