Hearing Loss Related to COVID-19 Infection

The good news appears to be that there is no increased risk of hearing loss after getting the COVID-19 vaccine. This is based on the latest evidence by the CDC and reported by Johns Hopkins neuro-otologist professor Dr. Wade Chien.

The unwelcome news is there is increasing evidence that patients with the 2019 Coronavirus disease (COVID-19) do have a risk of developing a special type of hearing loss called sudden sensorineural hearing loss.

This is the type of hearing loss that has the word “sudden” in its name, so it can happen without warning. It is usually unilateral or one-sided. It affects the nerve that supplies hearing information to the brain. Lastly, it is not clear why it happens or how to fix it.

What is sudden sensorineural hearing loss?

Sudden hearing loss can be frightening. We all depend so much on our hearing, and even when it diminishes slightly, it is very noticeable. A small plug of wax can cause a lot of irritation.

But sensorineural hearing loss, particularly sudden sensorineural hearing loss, is different. Hearing loss involves the hearing nerve, and it is not always something that can be easily diagnosed or treated.

It is estimated that up to 20 people suffer from sudden sensorineural hearing loss per 100,000 persons in the United States each year. The number of people may be higher than that for two reasons: the person ignores it, or it goes away even before seeking medical treatment.

The incidence of sudden sensorineural hearing loss seems to be equal with female-to-male distribution, and it can affect all age groups. However, this type of hearing loss is rarer in the elderly and children.

Sudden onset of sensorineural hearing loss is defined as having no identifiable etiology with consecutive hearing tests that show consecutive frequency losses over 30 dB within 72 hours.

Why does sudden sensorineural hearing loss happen?

It is unknown whether COVID-19 infection can directly cause hearing loss, but it is possible since the virus enters the ear, the nose, and the eustachian tube.

It is postulated that sudden sensorineural hearing loss can result from a viral infection. Some studies report that as many as 25% of patients who present with sudden sensorineural hearing loss have experienced a viral-like illness within a month of presenting to their ENT doctor.

Other studies show that the virus can cause injuries to the inner structure similar to the damage seen in patients with other viruses causing hearing loss like mumps, measles, and maternal rubella.

Therefore, it is not too much of a stretch to imagine that the COVID-19 virus can cause similar destruction resulting in hearing loss.

There seem to be more reported cases of sudden sensorineural hearing loss associated with COVID-19 (SARS-CoV-2) infection as the research develops.

It seems that the COVID-19 virus gets direct access to the labyrinth or inner ear and the cochlear nerve (hearing nerve). The COVID-19 virus may reactivate a latent virus inside the inner ear, which can cause damage or disrupt the immune system enough to cause hearing loss.

What do we know about COVID-19 infection and hearing loss?

We do know that COVID-19 (SARS-CoV-2) infection:

• Is highly transmissible.
• Can affect multiple organ systems.
• Can invade the central and peripheral nervous systems to cause various neurologic diseases.

Interestingly, as many as 10% of COVID-109 patients with self-reported loss of taste and smell (chemosensory loss) have complained about hearing loss at some point.

Many of these reports have been limited, however, because the patients are only self-reporting, and there are no hearing tests to document the findings in every case. It could be that the hearing loss goes away as quickly as it arrives.

Treatment for sudden sensorineural hearing loss

Before discussing treatment, it is important to emphasize to everyone that an early diagnosis of hearing loss may be beneficial. That means if a person has a COVID-19 infection, it is vital not to wait to get a hearing test, even if the hearing seems to be fluctuating or coming back.

This is true for anyone who suffers from sudden sensorineural hearing loss of any cause.

The reason is that often glucocorticoids or steroid treatment seems to have potential benefits, particularly if administered early. Glucocorticoids may be administered orally, intravenously, or intramuscularly via systemic (bloodstream) or through the eardrum (intratympanic) routes.

Some older treatments for sudden sensorineural hearing loss involve hyperbaric oxygen therapy and oral mesoglycan, a substance obtained from cow lungs, cow blood vessels, or pig intestines, which has been shown to increase long-term blood flow in the brain and oxygenation.

The prognosis for sudden sensorineural hearing loss with a COVID-19 infection

The cure rate is unknown, unfortunately.

The results can range from no improvement to partial recovery and even complete recovery. Most patients have at least some partial recovery of their hearing.

Again, a key factor in treatment success is early diagnosis and treatment.

Other symptoms that may be associated with sudden sensorineural hearing loss and COVID-19 include:

• Tinnitus (ringing).
• Vertigo.
• Dizziness.
• Ear pain.
• Facial weakness.

Beware the signs and symptoms

Sudden sensorineural hearing loss with COVID-19 is rare but does occur. It is important to report signs and symptoms immediately to prevent permanent hearing loss. With the right treatment and proactivity, the effects can be lessened or reversed.