Sensorineural Hearing Loss Post-COVID-19 Infection: An Update

Abstract

The course of COVID-19 infection may be complicated by a variety of neurological manifestations. Since the inner ear is vulnerable to viruses, sensorineural hearing loss (SNHL) has been reported to occur following the SARS-CoV-2 infection, often resulting in long-term morbidity and worsening the quality of life. The interest in how the virus affects the inner ear has gradually increased since the pandemic’s spread, but little is still known about the SNHL potentially caused by SARS-CoV-2. The aim of this paper is to evaluate the possible association between SNHL and COVID-19 infection, through a systematic literature review. Currently available data suggest that SARS-CoV-2 may hamper cochlear function; however, available reports are still limited. Large cohort and prospective studies are necessary to evaluate the long-term effects of this viral infection in the inner ear.

COVID-19 and sensorineural deafness: systemic review

“…Besides, Fancello et al affirmed that viruses are more prone to affect the inner ear (semicircular canals and cochlea), and COVID-19 being a virus, has high potential to cause hearing loss within ten days to two months of infection. 2,3,6 "The high rate of chemosensory impairment in COVID-19 patients endorses the neuro-invasiveness features of SARS-CoV-2, and the olfactory nerve may represent the virus entry point to the central nervous system". 2 A more intriguing publication is Fidan et al retrospective study.…”

“…2,3,6 "The high rate of chemosensory impairment in COVID-19 patients endorses the neuro-invasiveness features of SARS-CoV-2, and the olfactory nerve may represent the virus entry point to the central nervous system". 2 A more intriguing publication is Fidan et al retrospective study. The research measured the incidence of SSNHL-COVID related from December 2019 to September 2020.…”

“…1 On 28 May 2020, there were over 5.7 million confirmed cases and over 350,000 covid related deaths globally. 2 Many individuals have been affected and many more continue to suffer from the short term as well as long-term impacts of SARS-CoV-2. According to Fancello et al, "neurological symptoms have been reported to be present in more than 80% of severe cases and could be related to the virus' neurotropic and neuroinvasive properties".…”

“…According to Fancello et al, "neurological symptoms have been reported to be present in more than 80% of severe cases and could be related to the virus' neurotropic and neuroinvasive properties". 2 The inner ear is very susceptible to viruses, and multiple studies showed the evidence that SARS-CoV-2 is linked to sudden sensorineural hearing loss (SSNHL). Sudden sensorineural hearing loss is defined as abrupt hearing impairment of 30 decibels or more extraordinary at three successive frequencies over three days.…”

“…1,3 In April 2020, Sriwijitalai and Wiwanitkit presented the initial link between COVID-19 and sensorineural hearing loss, since then, the emphasis on how the virus impacts the inner ear has been risen. 2,4 According to Meng et al, "strong evidence suggests that viral infection is a cause of SSNHL. It may be related to direct effect of virus on the labyrinth or the cochlear nerve, reactivation of latent virus inside spiral ganglia, and immunoregulation of systemic viral infections.…”