Otitis media is an ear infection that affects the middle part of the ear. It involves a build-up of fluid behind the eardrum which can put pressure on the eardrum, often causing discomfort or pain. Respiratory infections, including the common cold, are infections involving the parts of the body used to breathe. They are often caused by a virus, most commonly the rhinovirus. They can spread to others easily because symptoms like coughing and sneezing release the virus into the air in tiny droplets, which can be inhaled by others within a distance of less than 6 feet.

Otitis media is often linked to a common cold or respiratory infection, as the microorganisms that cause these illnesses can travel to the middle ear through the eustachian tubes connecting the back of the throat to the middle ear.¹ The eustachian tubes are responsible for allowing fluid and mucus to drain; however, colds and respiratory infections can lead to mucus buildup, causing the eustachian tubes to swell or become blocked. This reduces its ability to drain fluid effectively, making it easier for infections to spread to the middle ear.

What is otitis media?

Otitis media includes acute otitis media, otitis media with effusion (commonly known as glue ear), and chronic suppurative otitis media.²

Acute otitis media

Acute otitis media refers to an ear infection of the middle ear caused by a build-up of infected fluid behind the eardrum. This puts pressure on the eardrum, often causing inflammation, discomfort, or pain. The main symptoms include earache, fever, feeling sick, having low energy, and experiencing slight hearing loss. Children and babies with acute otitis media may pull or rub their ears, not respond to some sounds, be irritable, and have reduced appetite. They may also lose their balance easily.  

Otitis media with effusion 

Commonly known as glue ear, serous or secretory otitis media is the buildup of fluid in the middle ear space without infection. This fluid accumulation is typically caused by a cold, sore throat, or a respiratory infection. It usually gets better on its own within 4-6 weeks. In some cases, the fluid buildup may continue, causing a temporary change in hearing ability; or the fluid may become infected, resulting in acute otitis media. Otitis media with effusion is more common in young children between the ages of 1 to 6 years.³ Due to a lack of obvious symptoms (unlike acute otitis media), it often goes undiagnosed and resolves itself.

Chronic suppurative otitis media

Chronic suppurative otitis media is also known as chronic otitis media. There is no infection present, but there is inflammation in the middle ear. This is because fluid has been trapped behind the eardrum for 3 months or longer.⁴ The presence of this ongoing trapped fluid can cause infections like acute otitis media to keep recurring. This condition is normally less painful than acute otitis media.

The mechanism behind otitis media and respiratory infections

There are three main parts of the ear: the outer ear, middle ear, and inner ear. A layer separates the outer ear from the middle ear, known as the tympanic membrane, or the eardrum.  Beyond the tympanic membrane (ear drum) marks the start of the middle ear. The middle ear contains three tiny bones (malleus, incus and stapes) which transfer sound vibrations to your inner ear. The middle ear also contains the eustachian tubes, which connect the ear to the back of the throat.⁵ These tubes have many functions including:

• To equalise pressure in the ear (to “pop” the ears by allowing air in to match the pressure between the outside and  inside of the ear)
• To allow fluid to drain
• To enable the clearance of mucus
• To provide local immune defence
• To provide protection against your own vocal sound

To summarise, the lower front part of the eustachian tube mainly helps clear mucus, and the upper back part of the Eustachian tube mainly helps with gas exchange and to aid equalisation of the ears.⁶

A viral infection of the respiratory tract or a cold can result in irritation of the eustachian tube, causing it to swell and narrow. This can reduce the tube's function of draining fluid, causing a buildup of fluid behind the ear drum. Bacteria and viruses can then grow in this fluid, causing an infection.⁷ It is often the same virus causing an initial upper respiratory infection that is responsible for the otitis media. The most common bacteria responsible for acute otitis media are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

Risk factors

There are several risk factors that increase the chance of getting otitis media. These include:

• Age: For children between the ages of 6 months and 2 years, this age group are at higher risk of developing ear infections because of the narrower size of their eustachian tubes and because their immune systems are still developing, making them more susceptible to colds and viruses
• Exposure to tobacco smoke or high pollution, usually with parents who are smokers
• Babies who drink from a bottle, especially when lying down, tend to have more ear infections than breastfed babies
• Attending daycare can lead to catching colds and viruses more regularly, which can lead to ear infections
• The presence of older siblings is more likely to lead to colds and viruses
• People with seasonal allergies may have a greater risk of ear infections when pollen counts are high
• People with Native American heritage has a higher incidence of ear infections
• People with Down syndrome due to differences in the anatomy of their ear structure

Symptoms of otitis media

Symptoms of otitis media often begin after an illness like a cold or a virus. They include:

• Ear pain or ear ache
• Loss of appetite
• Difficulty sleeping
• Difficulty hearing 
• A sensation that the ear is blocked
• Drainage from the ear of a yellow, brown or white fluid (this could be a sign that the eardrum is broken)

Symptoms in babies and young children

Young children and babies can’t always communicate their symptoms, so being able to recognise the signs of an ear infection is important.  A baby or a young child with an ear infection may:

• Pulling or rubbing on their ears
• Crying more than usual
• Becoming irritated
• Have a high temperature of 100.5 to 104 degrees Fahrenheit (38 to 40 degrees Celsius); however, only half of the cases of children having ear infections have high temperatures.
• Mouth breathing or suddenly starting to snore. This may be a sign of enlarged adenoids. Adenoids are small pads of tissue above your throat, behind your nose and near your eustachian tubes. They may become inflamed or infected with the same viruses or bacteria that cause ear infections, which could affect the normal function of eustachian tubes. 
• Refusal of meals or food. Swallowing could be painful for your child, as the pressure in the middle ear changes, causing more pain and a loss of appetite)

Diagnosis of otitis media

A visit to your doctor will normally be necessary for a physical examination of your child to gain a diagnosis. The doctor will use a special torch-like device (an otoscope) to look at the ears, throat and nasal passageways. The doctor may also want to listen to your child's breathing with a stethoscope.

Pneumatic otoscope

This instrument enables the doctor to look in the ear to see if there may be fluid trapped behind the eardrum. It works by gently puffing air against the eardrum so the doctor can see if there is any movement of the eardrum. If following the puff of air no movement is observed, this is usually because the middle ear is filled with fluid. Your doctor may also discuss with you other symptoms which may be present.

Additional tests

If your doctor is in any doubt about a diagnosis, or if the condition has not responded to treatments, your doctor may want to perform further tests:

Tympanometry 

This test involves using a device to seal off the ear canal and adjusting the pressure inside the canal to make the eardrum move. It measures how well the eardrum moves.

Acoustic reflectometry 

This test measures how much sound is reflected from the eardrum.

Tympanocentesis 

This is an uncommon test where the doctor pierces the eardrum with a tiny tube to drain the fluid, which can then be tested for viruses and bacteria. This can be used to find out why an infection has not responded to previous treatments.

Other tests

If your child has repeat ear infections or fluid buildup, a referral to a hearing specialist (audiologist), speech therapist, or developmental therapist for tests of hearing, speech skills, language comprehension, or developmental abilities may be required. 

Treatment

Ear infections often get better on their own within 3 - 5 days and do not require any treatment.

Children's pain relief medicines, containing paracetamol or ibuprofen, can be used to relieve pain and high temperature. The recommended dosage of the product should always be followed. A pharmacist will also be able to provide help and guidance on this. 

A warm cloth over the affected ear may also help to relieve discomfort. Antibiotics are not normally used to treat middle ear infections.

When to seek medical attention

You should seek medical attention if your child has:

• Symptoms that are not improving within 2 or 3 days
• Suffers from regular ear infections
• Is in a lot of pain
• There is a visible puss, fluid, or discharge coming from the ear
• Your child had an underlying health condition, such as cystic fibrosis or congenital heart disease, as these could make complications more likely

Summary

• Otitis media is an ear infection that affects the middle part of the ear
• Otitis Media is often linked to a common cold or respiratory infection as the same germs that caused these illnesses can travel to the middle ear
• The most common bacteria responsible for acute otitis media are: Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis
• Children between the ages of 6 months and 2 years are at higher risk of developing ear infections
• Ear infections often get better on their own within 3 - 5 days and do not need any treatment

Seek medical attention if:

• Symptoms that are not improving within 2 or 3 days
• Your child suffers from regular ear infections
• Your child is in a lot of pain
• There is a visible puss, fluid, or discharge coming from the ear
• Your child had an underlying health condition such as cystic fibrosis or congenital heart disease, as these could make complications more likely.