Swimmer's ear is America's most common waterborne illness

Learn about swimmer's ear, which sickens 1 in 10 Americans

This outer ear infection—in the tube leading from the ear opening to the eardrum—is usually caused by bacteria. Formally called otitis externa, this condition is commonly called swimmer's ear because microbes can enter the ear canal while swimming.

Swimming boosts the risk of contracting swimmer's ear by fivefold

The term swimmer's ear is a bit of a misnomer since other factors including scratches to your ear from Q tips, trapped perspiration inside the ear when you sweat, and living in tropical climates can elevate the risk of contracting this outer ear infection. But swimming poses the greatest risk: widely cited research has found that swimming elevates the risk of contracting this infection fivefold.

Swimmer's ear is not contagious

Though a lot of people may have symptoms of swimmer's ear at the same time at the same pool, that's because they are all swimming and the moisture is remaining in their ears—not because they are passing this bacterial or fungal-caused infection to each other. People of any age swimming in a pool, lake, or other body of water are all at risk, though children are considered particularly vulnerable.

Ear infections can arise from chlorinated water, too

Any water remaining in the ear can lead to swimmer's ear. Chlorinated water, however, can also strip the skin of the oils and wax that would otherwise protect the ear.

Doctors explain that most ear infections—but not swimmer's ear—affect the middle ear

A typical ear infection occurs in the area behind the eardrum, but swimmer's ear is an infection of the ear canal. Its characteristic symptom is pain whenever the ear is moved, though it can also include itching and a sense of fullness. Symptoms typically begin within a few days or a week of a water buildup not being addressed.

Exactly who coined the term 'swimmer's ear' remains unknown

There is no record of anyone being the first person to call otitis externa by its most commonly known name, swimmer's ear. The earliest known use of the term was in a 1917 news article, according to the Oxford English Dictionary. The article in Connecticut's The Day stated that the illness was appearing among swimmers and bathers that summer.

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Candida auris spreads easily in healthcare facilities and causes high death rates

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Read a study about racial differences in Lyme disease diagnosis

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This podcast walks through the investigation into the first US outbreak of West Nile, and how the virus had never been seen in the Western Hemisphere. The official discusses how she thinks the origin of West Nile in the US may have been birds or other animals that were brought here illegally.

Why we don't have an answer for the common cold

Since a landmark study of the common cold in 1925, researchers have learned much more about the seasonal ailment. Despite continuous study, people still contract colds for similar periods of time at the same rate with the same symptoms, and there's no vaccine. This article explains how the many viral strains make it hard to control.

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This real-time tracking of the hantavirus cruise ship outbreak in May 2026 offers a unique glimpse into the global reach of the outbreak and whether the virus sickened passengers and their communities around the world.

A pickleball's loud 'pop' sound can reach 120 decibels, which is equivalent to a hammer hitting a nail

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View the ten deadliest tornadoes in US history.

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In preparation for this weekend's Eurovision finale, which is something like the World Cup of pop music, here's a young Céline Dion performing (for Switzerland?) at the 1988 competition.

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