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

Before the pandemic began, we already knew that many different viral and bacterial infections such as measles, mumps and meningitis can cause hearing loss. Some viruses can cause sudden hearing loss, where patients notice a very sudden and dramatic drop in their hearing. In many cases, the cause is idiopathic; meaning we don’t always know what virus or bacteria caused the sudden hearing loss. If treated soon enough, most patients will regain their hearing once treated with steroids. (Sudden hearing loss is a medical emergency - if you or someone you know experiences a dramatic drop in hearing, make sure to contact us to arrange an urgent hearing evaluation! The sooner a sudden hearing loss is treated, the better the outcome). 

It is now known that the SARS-CoV-2 virus is also capable of causing hearing damage but we still don’t know very much about why and how this happens. We know that the tiny hair cells in the cochlea (the organ of hearing) are very sensitive to changes in oxygen and blood supply, and we know that COVID-19 infection can have a dramatic impact on oxygen levels and blood pressure. We know that autopsy reports have detected the virus in the bones of the middle ear as well as the mastoid bone (part of the skull behind the ear) according to a study published by the Journal of the American Medical Association (JAMA). We also know that according to a study published by the International Journal of Audiology, roughly 13% of patients (of 138 adults) admitted to a hospital in the UK reported changes in hearing since being diagnosed with COVID-19. 

This is all very interesting but there are some important points to consider. We also know that some of the risk factors for developing severe symptoms of COVID-19 infection are the same risk factors that increase your risk for hearing loss. Therefore, aging and underlying health conditions such as cardiovascular disease and diabetes increase a person’s risk for hearing loss as well as increase a person’s risk for severe COVID-19 infection. This means that if someone who is older with an underlying health condition gets diagnosed with COVID-19 and also experiences hearing loss, it is difficult to know if this hearing loss was caused from COVID-19, increasing age, an underlying health condition or all of the above.