Can COVID-19 Really Cause Hearing Loss?

The coronavirus isn't just frightening because of its high infection rate and the many deaths and hospitalizations it's caused. In many cases, it appears to also cause or contribute to multiple long-term, debilitating conditions. 

And hearing loss may be among them, as reported by Medical News Today.  

In what's frequently been referenced as Long COVID, there are more questions than answers. Many survivors of the disease have reported a myriad of symptoms, including brain fog, weakness, fatigue, nausea, and difficulty breathing. Although medical research is currently underway to identify whether the coronavirus indeed causes these conditions, the illness simply hasn't been around long enough for us to draw a concrete conclusion.

That isn't to say there hasn't been plenty of medical research, mind you. A yearlong study recently published in the International Journal of Audiology, for instance, notes that though there is a great deal of evidence tying COVID-19 to hearing loss, it's largely based on case reports and surveys rather than clinical trials. 

So what exactly do we know for sure?

• Many coronavirus patients have reported hearing changes such as tinnitus or sudden onset hearing loss long after the initial infection. 
• Other viral infections can contribute to or cause hearing loss. It is, therefore, not outside the realm of possibility that COVID-19 might be among them.
• Tinnitus appears to be one of the most prevalent conditions reported among patients, according to self-reporting questionnaires. 
• The coronavirus can enter the body in many ways, including by air. However, we don't yet know if airborne transmission can affect the ears in any fashion.
• Several cardiovascular issues have been reported, including impaired blood coagulation. And in more severe cases, COVID-19 can cause low blood oxygen saturation. Factoring in the vulnerability of cochlear hair cells, the restricted blood flow, and oxygen supply could cause permanent damage. 
• Although vertigo is a commonly reported symptom, people often tend to use the term interchangeably with dizziness. Rotary vertigo and common dizziness may feel similar, but they are entirely different conditions.

 

The waters are only further muddied by the fact that no standard test for tinnitus was used, along with there being confusion between advancing, sudden onset, and worsening tinnitus. Because tinnitus is often tied to neurological issues, anxiety and stress from the pandemic may contribute. In many cases, a patient may have even had tinnitus or other hearing issues before the pandemic. 

A patient on a ventilator or struggling to recover from COVID can't tell the doctor their ears are ringing or if they're experiencing asymmetrical hearing impairment. And medical staff, for their part, are often both overworked and more focused on the patient's comfort and care. We also lack comparative data related to how COVID impacts people with hearing loss versus those without. 

In short, there's no concrete way to confirm whether or not long COVID causes tinnitus or hearing loss. The best we have at this point are educated guesses. Perhaps sometime in the future, once there has been more time for research to be carried out, we'll know more.

For now, however, we simply don't have enough proven evidence.