People who suffer from mild Covid-19 infection could be at risk of sudden deafness and hearing loss, according to a study.
Sudden sensorineural hearing loss (SSNHL) -- also known as sudden deafness -- is a little known and poorly understood side effect of Covid-19 that is not even listed as a common symptom by doctors, said Kim Gibson, a fully vaccinated nursing lecturer at the University of South Australia.
Gibson, a registered nurse with a clinical background in neonatal intensive care, developed acute hearing loss in one ear, along with vertigo and tinnitus five weeks after experiencing a mild Covid infection in 2022.
Her experience is published in the British Medical Journal Case Reports.
"My experience shows that even people who have a minor Covid-19 infection could be at risk of potentially permanent and debilitating long-term effects. High quality, person-centred care is so critical."
Previous studies have linked SSNHL with Covid-19, as well as a potential side effect of Covid vaccination, but the evidence is still limited, Gibson said.
Gibson said that despite working in health education, she was not aware of Covid-19 causing hearing loss.
"This was a shocking experience for me that had a significant impact on my quality of life for several months as I had never had any problems with hearing before; not even an ear infection.
"I was unable to drive a car while experiencing severe vertigo. I needed to reduce my workload, negotiate flexible working hours with my employers and take a leave of absence from study. This was all due to a mild Covid-19 infection.
"I was worried that the hearing loss would be permanent and that I would need a hearing aid. I now feel very nervous about a second Covid-19 infection. What if I experience this again, or even worse?"
According to the Royal Australian College of General Practitioners, sudden sensorineural hearing loss - also known as sudden deafness - occurs when you lose your hearing very quickly, typically only in one ear.
It can happen instantly or over a span of several days. People can experience mild hearing impairment or total loss of hearing and it may be temporary or permanent.
After experiencing the sudden hearing loss Gibson was referred to an otolaryngologist (an ear, nose, and throat doctor, or an ENT) who confirmed SSNHL.
A course of oral prednisolone and betahistine was prescribed, and Gibson's hearing slowly improved over subsequent months, although she continues to experience intermittent tinnitus.
"The evidence around the short and long-term impacts of Covid-19 and vaccines is still emerging and the aim of this paper is to highlight the lesser-known side effects of the virus," Gibson said.
"We believe that clinicians should include sudden hearing loss as a potential side effect of Covid-19 when talking to patients. High-dose corticosteroids are a recommended first line of treatment for SSNHL and it is important that GPs promptly refer patients to specialists as soon as symptoms develop.
"Hearing loss and associated symptoms can have a significant impact on a person's quality of life -- they did in my case -- and are closely related with anxiety and depression," she noted
A study of hearing loss during the pandemic showed that approximately one third of patients with SSNHL were positive with Covid-19 when they were referred to an audiologist. Other studies reported an increase of SSNHL in 2020 and 2021, including among asymptomatic people.