How Does an Ear Infection Start?

Dr. K. R. Meghanadh

Ear infection, or Otitis, are common across all age groups. While most are mild and often resolve with minimal or no treatment, neglecting an ear infection can lead to serious complications. Understanding how ear infections start is crucial for prevention and timely treatment, ensuring long-term ear health.

Common Start Points of Ear Infection

There are many causes of ear infections, but here are some of the most common causes that cover the majority of ear infections.

Issues in the Nose

About 90% of ear infections start in the middle ear (otitis media) and are usually caused by infections in the nose.

The middle ear connects to the back of the nose through the eustachian tube, which helps balance air pressure for clear hearing.

Nasal infections can lead to ear infections in these ways:

• Infected fluids from the nose can travel to the middle ear.

• Shared lining: The nose and eustachian tube share a mucosal lining, so swelling caused in mucosal lining from a nasal infection can spread to the ear.

• Blocked eustachian tube: A blockage can create negative pressure in the middle ear, encouraging infection.

Keeping the nose and eustachian tube healthy is key to preventing ear infections.

Common Cold

Around 90% of middle ear infections (otitis media) start with a common cold. They also make up around 90% of all ear infections in humans.

During a cold, the nose produces excess mucus, which can affect the middle ear in multiple ways:

• Thick mucus: It can block the eustachian tube, creating negative pressure in the middle ear and leading to infection.

• Thin mucus: It may seep into the middle ear, directly causing an infection.

• Swollen mucosa lining: The mucosal lining is the thin skin covering the nose and part of the eustachian tube. During a nasal infection, this lining can swell, and the infection may spread to the eustachian tube. People with smaller or thinner eustachian tubes are more prone to frequent ear infections, especially when they catch a cold, as their tubes are more easily blocked or affected by swelling.

Managing or treating cold or nasal infections with home remedies early can significantly help reduce the risk of ear infections.

Blowing Nose can Start an Ear Infection

Blowing your nose forcefully during a cold, especially with one nostril blocked, creates high pressure in the nasopharynx (back of the nose). This pressure can:

• Push infected fluid from the nasopharynx into the middle ear through the eustachian tube.

• Block the eustachian tube.

Both scenarios can start middle ear infections (otitis media). To avoid this, blow your nose gently and clear both nostrils together. You can learn more about this from our article "Ear Pain after Blowing Nose."

Chronic Sinusitis

Sinusitis causes clogged ears and ear pain when neglected. Sinusitis progresses through stages:

• Acute Stage

• Subacute Stage

• Chronic Stage

• Acute on Chronic Stage

In the chronic stage, the infection is over 45 days old, and the infection lingers with minimal symptoms, often making people forget about the infection for years.

In chronic sinusitis, fluids drain from the back of the nose into the throat without alarming the patient, but potentially causing middle ear infection:

• Thick fluids: Can block the tube, creating negative pressure in the middle ear, leading to otitis media.

• Thin fluids: May seep into the middle ear, directly causing infection.

Proper treatment of sinusitis is key to preventing complications like middle ear infections.

Home Remedies that can Start Ear Infection

This may sound astonishing, but yes few commonly used home remedies for ear can start an ear infection or worsen any existing ear infection.

Oil as Ear Drops

Many people assume that itchy or irritated ears are due to dryness in the outer ear canal and use oil drops for relief. However, the itch could be caused by a fungal infection too. Addition of oil to ear canal creates an environment that promotes fungal growth, which can start a new infection or worsen an existing infection. If the infection is already existing, the oil will promote the fungal growth and the infection will spread faster and can trigger new complications. This fungal ear infection is called Otomycosis.  To avoid complications, it’s always best to consult an ENT specialist for any ear discomfort.

Unprescribed Ear Drops or Over-the-Counter Medications

Using over-the-counter ear drops without a prescription may damage the ear canal and make the infection worse. The outer ear naturally maintains a balance between bacteria and fungi to keep each other in control. However, using over-the-counter ear drops without proper diagnosis and prescription will disturb this balance, allowing fungi to grow unchecked. This can start a fungal ear infection, causing Otomycosis.

How Does an Ear Infection Start in Babies?

Ear infections in babies is very common, primarily due to their unique anatomy and feeding habits.

In babies under six months, the tubes that connect the nose and ear (called auditory tubes) are positioned more horizontally because their heads are still small. These tubes help supply air to the middle ear. In adults, the tubes are more vertical or slanted, so fluids are less likely to flow into them. But in babies, because the tubes are flat, it’s easier for milk to travel from the mouth into the middle ear. Milk in baby ear can create a moist environment, leading to an ear infection.

Babies often fall asleep with milk in their mouths. Milk left in the mouth can ferment quickly due to bacteria naturally present in the oral cavity. If this fermented milk travels to the middle ear through the auditory tubes, it can lead to infection. So, it is important to feed a baby in a slant position and burp them after the feed.

How does an Ear Infection Start in Kids?

One of the most common causes of ear infections in kids is enlarged adenoids. Adenoids are glands located at the back of the nasal cavity. They are enlarged due to allergies or viral infections affecting the nasopharynx (the area behind the nose). When the adenoids swell, they can block the opening of the eustachian tube. This blockage causes a buildup of negative pressure in the middle ear. As a result, fluid can accumulate in the middle ear, creating an ideal environment for infection.

Conclusion

By understanding how an ear infection starts, you can often prevent it. Even if you can’t altogether avoid it, this knowledge can help you identify an ear infection early and take the necessary action. Early treatment is important, as untreated or neglected ear infections can lead to serious and irreversible complications.

Dr. K. R. Meghanadh