Swimmer's ear is not contagious

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.

Children are at increased risk of contracting swimmer's ear

Kids may be more likely to spend time at the pool so they have that water exposure. They also tend to have narrow ear canals, a prime location for water to get trapped. Frequently wearing earbuds or excessively trying to rid ears of earwax, however, can also increase the chances of painful swimmer's ear infections at any age.

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.

Explore why swimmer's ear will not go away on its own

This infection is typically treated with ear drops to reduce inflammation and fight the bacteria or fungus that led to the issue. But without treatment, complications can arise, including a deep tissue infection, bone or cartilage damage, or—very rarely—spreading beyond the ear into the skull bones and surrounding areas.

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.

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.

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

Federal government analysis of the roughly 7 million waterborne illness cases that occur annually in the US found that swimmer's ear comprises some 4.7 million, or 65%, of the annual waterborne illnesses and 20% of hospitalizations. Norovirus infection comes in second place.

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.

Listen to why extensive ear rinsing can create problems

The clinician who hosts this podcast discusses how his patient developed swimmer's ear after he flooded his ears with water during his daily showers, ostensibly to clean them. The resulting itchy, painful ears were the result of removing protective earwax in the ear and also altering the typical pH of the ear.

Surfer's ear, from repeated cold water exposure, leads to new bony protrusions in the ear

Frequent exposure to icy cold water, typical in surfing, can cause tiny bony growths to develop in the ear canal, informally called surfer's ear. While the exact cause for these growths is unknown, it may be the body's protective response to shield the ear drum from the cold. These protrusions can heighten the risk of swimmer's ear, lead to wax buildup, and result in hearing loss.

Watch how to safely remove water from your ears

Do not stick a Q-tip into the ear canal—it can cause microtears of the delicate skin there and elevate infection risks. Instead, try tapping on the side of your tilted head after swimming to break the surface tension so water will drip out, or pulling your earlobe in different directions while the ear is pointed downwards. Another suggested approach is to place a few droplets of isopropyl alcohol or over-the-counter eardrops inside the ear to speed evaporation. If those approaches don't work, consider contacting your physician.

See why wearing earbuds—instead of over-the-ear headphones—can cause ear infections

Earbud headphones can heighten the risk of ear infections. They can lead to earwax buildup and create a dark, moist environment as you sweat—ideal conditions for germs to thrive. Wearing external over-the-ear headphones or ones that don't enter deep into the ear canal can help.

We can get food poisoning from spending time in swimming pools, lakes, rivers, and ponds

Some of the same pathogens that may sicken us in food or water may also sicken us in recreational swimming environments. Bacteria can rub off of people’s (or animal’s) bodies or contaminate the water through a diarrheal episode. Washing your hands for at least 20 seconds before eating food if you are at the beach, pool, or other similar environments and being sure not to swallow the water are ways to help keep safe.

Some men may be at elevated risk of inheriting tinnitus

A 2017 Swedish Twin Registry study suggests that bilateral tinnitus—when tinnitus occurs in both ears instead of just one—appears to be heritable, at least in men.

There's no cure for Ménière's disease, only medications to reduce frequency of attacks

Ménière's disease is an inner ear problem that can cause vertigo and hearing loss. Most of the time, Ménière's disease affects only one ear.

Measles is one of the most contagious preventable diseases

The virus’s ability to persist in the air for up to two hours means an infected person could enter a room, leave, and two hours later infect someone else entering the room. Its location in the body’s upper respiratory tract also makes it easy for viral particles to be sneezed or coughed into the air.

Most people breathe fungal spores daily without getting sick

Most people breathe in hundreds of Aspergillus fumigatus spores daily without getting sick—it’s a common microscopic fungus in our environment. But people who are severely ill, including those who have undergone an organ transplant, are at risk of developing infections from these spores.

Fear (and stress) can be contagious via pheromones secreted by the body

While seeing someone else in a panicked state may induce a stress response, researchers have found stress can be literally contagious—chemicals contained in sweat and other secretions can trigger stress hormone release in others. Theories suggest this feature is an evolutionary adaptation to protect groups from danger.

Heatstroke is sometimes missed because the patient is really sweaty

Since the condition involves losing the ability to cool oneself, clinicians sometimes see someone who has exertional heatstroke—like a high school athlete who is really sweaty—and don't realize the heat-related illness has already progressed to heatstroke. Classic heatstroke typically occurs among the very young or the elderly. (Some users may encounter a paywall.)

Leprosy symptoms may appear 20 years after infection, so contact tracing isn't possible

The standard approach for tracking disease transmission isn't realistic for this disease because symptoms may take decades to manifest. As a result, disease transmission is still not fully understood.

Poison ivy can cause rashes any time of the year

This myth-busting article about poison ivy notes that all parts of the plant contain urushiol, the oil that triggers our allergic response, so if you are in the woods in winter you may be still encounter the plant—and urushiol.

Ringworm is caused by a fungus, not a worm

Ringworm, formally known as tinea and known for its red circular rash, is responsible for about 325 million infections at any given time—comprising roughly half the world’s fungal skin infection burden. It’s caused by a type of fungus called a dermatophyte, which also causes athlete’s foot and jock itch. Doctors typically prescribe antifungal tablets or powders to stamp out these fungal invaders.

There's no cure for West Nile virus—and infection can leave patients with permanent symptoms

This news story features Marie Heilman, a woman who became ill at age 40 from an infected mosquito bite in her yard. She says she was in a coma for 15 days, and though she woke up, she suffers from seizures, fatigue, vision issues, and has had two strokes.

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

Poison ivy can cause rashes year-round since all parts of the plant contain urushiol, the oil that triggers our allergic response.

The similarly named foot-and-mouth disease doesn't affect humans, unlike HFMD

Though the names are similar, foot-and-mouth disease—also known as hoof-and-mouth disease—exclusively affects animals, primarily those with hooves, such as cattle, sheep, pigs, goats, and even giraffes. It doesn't sicken humans, though both this disease and hand, foot, and mouth disease do come from the same family of viruses—Picornaviridae.

Repeated head injuries can lead to CTE and early dementia

Chronic traumatic encephalopathy is a progressive neurodegenerative disease caused by repeated trauma to the head. The condition has become a particular concern in sports like football and soccer, from youth to professional leagues, where repeated low-level concussive events are likely.

Fish populations in the Great Barrier Reef have increased after installing waterproof speakers on the ocean floor that played recordings of sounds from healthy coral reefs.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

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