If the Eustachian tube that connects the nose and ear becomes blocked, bacteria and mucus can become trapped in the middle ear, causing the area to become inflamed and infected.
Children are more vulnerable to otitis media than adults because their Eustachian tubes are smaller and thus more likely to become blocked. Additionally, children are more susceptible to upper respiratory tract infections such as colds, which can cause congestion of the Eustachian tube, increasing the likelihood of ear infection.
Middle ear infections are common in children from the ages of 4 months to 4 years old, but in particular from 6-18 months of age. In addition, the following factors increase children’s susceptibility:
Recent or recurrent upper respiratory tract infections (e.g. colds and flu) or allergies
- Exposure to cigarette smoke, smoke from wood-burning stoves, fumes, or air pollution
- Attending daycare
- Using a dummy, especially at 12 months of age and older
- In babies, drinking from a bottle or being breast-fed while lying down
- Having a cleft palate or Down’s syndrome
- A family history (parents or siblings) of ear infections
As it’s name suggests, swimmer’s ear often develops after swimming in contaminated water, but may also occur any time that water becomes trapped in the ear canal, creating an environment that’s hospitable for bacteria to multiply in. This is more likely to occur if the ear canal is obstructed for some reason, too little earwax is present (which may be a consequence of spending a large amount of time in water) or the tissues of the ear are damaged.