Ear Infections - What Happens

What Happens

Middle ear infection (acute otitis media)

Middle ear infections usually occur along with an upper respiratory infection (URI), such as a cold. During a URI, the lining of the eustachian tube can swell and block the tube. Fluid builds up in the middle ear, creating a perfect breeding ground for bacteria or viruses to grow into an ear infection.

Pus develops as the body tries to fight the ear infection. More fluid collects and pushes against the eardrum, causing pain and sometimes a loss of hearing. Fever generally lasts about 1 to 2 days; pain and crying usually last for 3 to 4 hours. After that, most children have some pain on and off for up to 4 days, although young children may have pain that comes and goes for up to 9 days. Treating children with antibiotics shortens these symptoms by about 1 day, according to a study of 240 children ages 6 months to 2 years.³ However, about 80% of the time the immune system can fight infection and heal the ear infection without the use of these medicines.⁴

In severe cases, too much fluid can increase pressure on the eardrum until it ruptures, allowing the fluid to drain. When this happens, fever and pain usually go away and the infection clears. The eardrum usually heals on its own, often in just a couple of weeks.

Sometimes complications, such as a condition called chronic suppurative otitis media (an ear infection with chronic drainage), can arise from repeat ear infections.

Middle ear fluid buildup (otitis media with effusion)

Most children who have ear infections still have some fluid behind the eardrum 2 weeks after treatment for an ear infection. In most cases, the fluid clears in 1 month. However, about 10% of children still have fluid buildup (effusion) 3 months after an ear infection clears.¹ Hearing problems can result because the fluid affects how the middle ear works. This condition is called otitis media with effusion. Usually, infection does not occur.

Otitis media with effusion may occur even if a child has not had an obvious ear infection or upper respiratory infection. This is due to some other cause of eustachian tube blockage.

In rare cases, complications can arise from middle ear infection or fluid buildup. Examples include hearing loss and ruptured eardrum.