Johannesburg - Across Gauteng audiologists are seeing a lesser known consequence of the Covid-19 pandemic – they are treating patients with hearing loss.
The concern is that it is unclear just how widespread the problem is or if many of these patients will fully recover their hearing.
In Pretoria one audiologist, who didn’t want to be named, said it is now common to ask her new patients if they have had Covid-19.
“There certainly appears to be, among my colleagues and their patients, an increased incidence of hearing loss in those who've been infected with Covid,” said Michelle Kinnear, a corporate audiologist working with a hearing aid manufacturer, who has contact with audiologists across the country.
“We are also noting an increase in vestibular (balance) issues as well as reported tinnitus (ringing in the ears). For some patients, these symptoms are ongoing, some say it may have settled down somewhat.”
It is a problem that has been noted around the world. In a study published in the International Journal of Audiology it is estimated that between 7 and 15% of adults diagnosed with Covid-19 reported hearing-related problems.
“The Delta variant has been the strain of most concern, as experts indicate that Delta is potentially 40-60% more transmissible than previous strains, and more viral particles appear to be found in the airways of patients infected with the Delta strain,” explained Kinnear. “This means that more patients are experiencing symptoms similar to those of upper respiratory tract infections, which could certainly affect the state of the ear (blocked ears, pain, swelling, etc).”
The concern, voiced by audiologists, is that hearing loss can have a detrimental impact on an individual’s health. Research has linked it to heart attacks, falls, depression and even an increase in suicide risk.
Professor Shabir Madhi, professor of vaccinology and director of the South African Medical Research Council Respiratory and Meningeal Pathogens Research Unit at the University of the Witwatersrand, said given the nature of the virus, it is not surprising it has an effect on hearing.
“The consequences of Covid-19 infection results in multi organ dysfunction. So it wouldn't be too surprising should audiologists start seeing some cases of hearing impairment post recovery from Covid-19.
“There are a number of other neurological manifestations that are also evident, including Covid-19 presenting as an example with what is referred to as Guillain Barre Syndrome, which is a form of paralysis.”
It is not just recovered Covid-19 patients who are presenting with auditory problems, some patients are claiming to have suffered hearing loss after being vaccinated. There have also been reports of this overseas.
It is not just hearing loss, some recently vaccinated individuals claim to have balance related issues and tinnitus. There have been suggestions that these could be stress and anxiety related.
Madhi, however, said that there was no scientific data that suggested hearing impairment was linked to the Covid-19 vaccination.
“It's not correct to attribute causality to vaccination simply because someone has been vaccinated,” he added.
A new study, however, might have uncovered how Covid-19 causes hearing loss. The study conducted by the Massachusetts Institute of Technology and Massachusetts Eye and Ear found evidence that the virus infects cells of the inner ear, including hair cells that are critical to balance and hearing.
The pattern of infection they found in human inner ear tissue related to the symptoms seen in 10 Covid-19 patients who had reported ear-related issues.
The researchers hope in the future to use their work to test possible treatments for inner ear infections caused by Covid-19.
But a pressing concern is working out how widespread hearing loss is among Covid-19 survivors.
“We still don't know what the incidence is, but our findings really call for increased attention to audiovestibular symptoms in people with Covid exposure,” said one of the researchers Konstantina Stankovic, in a statement.