An ear infection, or otitis media, is a bacterial or viral infection that affects the middle ear. This condition impacts both adults and children. However, it is much more common in childhood, and statistics show that about two-thirds of children under the age of 3 years will have at least one ear infection.
Otitis media can be acute or chronic. The former is an ear infection that develops suddenly, leading to swelling, redness, fever, pain, and irritability. However, chronic ear infections may occur repeatedly or not clear up quickly. Sometimes, a chronic ear infection in adults can cause permanent ear damage.
Pathophysiology and Risk Factors
Generally, otitis media develops due to the presence of a virus or bacteria in the middle ear. A fungal ear infection may also occur in some cases. Other illnesses may also predispose a person to an ear infection, including the common cold, allergies, or the flu. These cause swelling and congestion of the throat, nasal passages, and the Eustachian tubes.
When the eustachian tubes become swollen, whether this is due to infection of the middle ear or another condition, fluids can build up in the middle ear. This presents as the symptoms of pain and swelling often associated with ear infections.
This condition is more common in kids due to narrower Eustachian tubes, which hinder fluid from draining. Adenoids also play a significant role in otitis media. These tissues are present at the back of the nose and are involved in the activity of the immune system. Located near the openings of the Eustachian tubes, swelling of these tissues can block the tubes, increasing the chance for infection. The adenoids of children are relatively larger than those of adults. Therefore, they play a more significant role in ear infections in children.
Common risk factors for the development of otitis media are:
- Age – The size of adenoids and eustachian tubes predisposes children between 6 months and two years to ear infections. Ongoing development of the immune system during childhood is a further contributing factor.
- Seasonal factors – Winter and fall seasons put people at risk of ear infections. During these seasons, pollen counts are high, affecting people with seasonal allergies. Tendency to stay indoors also aids in the spread of pathogens.
- Poor air quality – High levels of air pollution and exposure to smoke increase the risks of otitis media.
- Cleft palate – children with cleft palates often have different bone and muscle structures. Thus, their eustachian tubes may not drain well.