As we continue to learn to live with the SARS-COV-2, or the COVID-19 virus, much more is being learned about how the illness affects the human body. Since the early days of the pandemic, it was noted that individuals with the virus often lost their sense of taste and/or smell. But it seems now more COVID-19 patients are reporting symptoms affecting their sense of hearing, including hearing loss, dizziness and tinnitus. This suggests the virus may be able to infect the inner ear.
According to an article that appeared in the Scientific American, more than 10 percent of people who get COVID develop some type of eye or ear symptom which may last for a long period of time. Individuals also may need to take note of hearing or balance problems as potential warning signs that they’ve been infected with the virus, and that they need testing.
The Impact on Your Ears
An audiologist from Canada studying this phenomenon reported in a 2021 meta-analysis that dizziness or vertigo was detected in 12% of COVID patients; tinnitus in 4.5%; and hearing loss in 3%. One theory is that inflammation caused by the virus may directly impact the auditory system, though this is difficult to verify due to the complexity of the inner ear.
Another study from the Massachusetts Institute of Technology and Massachusetts Eye and Ear has offered evidence that the virus can infect cells of the inner ear, including hair cells, which are critical for both hearing and balance.
The researchers used novel cellular models of the human inner ear that they developed, as well as hard-to-obtain adult human inner ear tissue, for their studies. The limited availability of this tissue had hindered previous studies of COVID-19 and other viruses that can cause hearing loss.
The pattern of infection that the researchers found in their tissue samples appeared to correspond to the symptoms observed in a group of 10 COVID-19 patients who reported ear-related symptoms following their infection. Nine of these patients suffered from tinnitus, six experienced vertigo, and all experienced mild to profound hearing loss.
Possible routes for the virus to enter the ears include the Eustachian tube, which connects the nose to the middle ear. The virus may also be able to escape from the nose through small openings surrounding the olfactory nerves. That would allow it to enter the brain space and infect cranial nerves, including the one that connects to the inner ear.
While this study strongly suggests that COVID-19 can cause auditory and balance problems, it is a very small study. The overall percentage of COVID-19 patients who have experienced ear-related issues is not known.
These researchers now hope to use their human cellular models to test possible treatments for the inner ear infections caused by COVID-19 and other viruses.
Until more answers are available, be aware that although it’s rare, COVID-19 may affect your hearing and balance systems. If you test positive for the virus and notice problems with your hearing or balance, be sure to follow up with your physician or an audiologist for further testing and possible treatment, if necessary.
Again, because this virus is so new, it may be years before the long-term complications are known. Schedule an appointment with a doctoral-level audiologist if you suspect hearing or balance issues related to a COVID-19 infection. We follow all recommendations from the Centers for Disease Control to ensure the safest possible environment for your care.