The COVID-19 pandemic is being increasingly linked to causing long-term, lingering health issues in the heart, lungs, and blood. When it comes to your hearing, there is growing evidence that suggests it may be linked to hearing loss and tinnitus.
There are other viruses and infections that are known causes of hearing loss, such as mumps, measles, and meningitis. While there has yet to be any large-scale research that fully explains how and why COVID-19 causes hearing loss, there is now research linking the two.
Here is an explanation for everything that is known about the link between COVID-19 and hearing loss.
There have been several pathophysiological processes proposed regarding how audiovestibular disorders are caused by COVID-19. Viral involvement can cause cochleitis or neuritis of the inner ear or auditory nerve. Antibodies or T-cells could damage the ear if they mischaracterized inner ear antigens as the virus. Sudden hearing loss may also be a result of cochlear ischemia or hypoxia, due to the cardiovascular abnormalities associated with COVID-19. Finally, the virus may trigger immune-mediated inflammation that causes hearing loss, such as inflammation of the meninges.
There are published case studies that cite COVID-19 as the reason for a sudden sensorineural hearing loss (SSNHL). Sudden sensorineural hearing loss is when there is a change in hearing because of an issue in the inner ear (the cochlea) or the nerves beyond that which happens within a very short time.
The most common cause of sensorineural hearing loss is natural aging, and that happens as the cochlear hair cells degrade over time, usually several years. When that happens, you slowly lose sensitivity to sound and have a more difficult time hearing as clearly. The other most common cause of hearing loss is due to loud noise.
Although the direct reason that COVID-19 may cause sudden sensorineural hearing loss is unknown it may be due to changes in blood flow to the cochlea, inflammation of the inner ear or auditory nerve, or the virus may trigger inflammation in the area surrounding the inner ear.
Even in patients who do not report any changes in hearing there may be an effect. One study tested 20 people who were positive for COVID-19 and tested their hearing against a control group who were negative for COVID-19. The results showed that people who were COVID-positive — even if they didn’t show any symptoms — had “significantly worse” high frequency hearing loss. The study was also able to show that those who tested positive for COVID-19 had deterioration to their outer ear hair cells, which help transmit sounds in the inner ear.
There is also a potential link between the coronavirus and tinnitus — a hearing disorder characterized by hearing a ringing, buzzing, or hissing sound in your ears. One professor of Audiology at Manchester University in England performed a study on COVID-19 patients who were hospitalized.
Kevin Munro interviewed 139 patients and asked them if they experienced changes in their hearing. Some reported that their hearing seemed worse, while eight patients reported tinnitus symptoms.
It is worth noting that there has been no research to confirm that COVID-19 can cause tinnitus, but there are two potential theories to explain how it can happen.
It is also important to note that tinnitus has links with both stress and anxiety, which can be more prevalent during a global pandemic, regardless of whether someone has COVID-19 or not.
If you test positive for COVID-19 it is important to seek medical management and follow all provincial guidelines.
If you notice a change in your hearing inform your physician as there are medical management strategies for sudden sensorineural hearing loss that may be of benefit to you.
There is still a lot that we have to learn about COVID-19 and how it affects hearing and tinnitus. However, these are symptoms that should not be ignored.
If after an infection you notice a change in your hearing or new tinnitus it is a good idea to get your hearing checked. You can request a hearing assessment at any hearing clinic.You Might Also Be Interested In...
Steven Reinberg HealthDay Reporter. “Another Effect of Covid: Lasting Hearing Problems?” WebMD. WebMD, July 31, 2020. https://www.webmd.com/lung/news/20200731/another-side-effect-of-covid-19----lasting-hearing-problems.