8Infections and Post-infective Tinnitus

FWhy infective tinnitus is worth chasing

Infections matter in tinnitus out of all proportion to their frequency, because they are the rare causes where a specific treatment can change the outcome. A correctly identified spirochaete or virus may be answered with antibiotics or antivirals; a missed one may leave irreversible hearing loss and chronic tinnitus.

The infective mimics share a common trait: tinnitus rarely arrives alone. It travels with hearing loss, vertigo, facial weakness, rash, fever, headache or a recent viral illness. The clinical skill is to read those companions and to think of the treatable few — Lyme disease, syphilis, viral labyrinthitis, herpes zoster oticus, and the post-viral state including post-COVID tinnitus [2013].

TLyme disease and neuroborreliosis

Lyme disease, caused by Borrelia spirochaetes transmitted by ticks, can involve the audiovestibular system, particularly when it disseminates to the nervous system as neuroborreliosis. Sensorineural hearing loss and tinnitus are recognised, if uncommon, manifestations, and can occasionally be the presenting feature in an endemic setting [2024].

The diagnostic clue is the wider story: a tick-exposure history, the erythema migrans rash, arthralgia, facial palsy or other cranial neuropathy, and serology with confirmatory testing. The reason to pursue it is that early antibiotic treatment can halt progression, making Lyme one of the genuinely reversible infective causes of audiovestibular symptoms.

TOtosyphilis and neurosyphilis

Syphilis has long been called a great imitator, and the ear is one of its disguises. Otosyphilis can produce fluctuating or progressive sensorineural hearing loss, tinnitus and vertigo that mimic Meniere disease or sudden sensorineural hearing loss, and it may appear at any stage of infection, frequently alongside neurosyphilis [2025].

It is worth excluding because it is treatable: penicillin-based regimens, often with corticosteroids, can stabilise or partly reverse the auditory damage if started early. The catch is that the presentation is non-specific, so testing must be deliberate — serological screening with treponemal and non-treponemal tests, with cerebrospinal fluid examination when neurosyphilis is suspected. A rising incidence of syphilis in many regions makes this an exclusion worth remembering in unexplained, fluctuating audiovestibular disease.

CViral labyrinthitis and Ramsay Hunt syndrome

Acute viral inflammation of the labyrinth typically follows a viral illness and presents with sudden vertigo and, when the cochlea is involved, hearing loss and tinnitus. Most viral labyrinthitis is self-limiting, with vestibular compensation over weeks, but residual tinnitus can persist.

Herpes zoster oticus — Ramsay Hunt syndrome — is the reactivation of varicella-zoster virus in the geniculate ganglion, producing the triad of ear pain, a vesicular rash in the auditory canal or auricle, and ipsilateral facial palsy, often with tinnitus, hearing loss and vertigo. Outcomes are better than facial palsy alone might suggest, but recovery is incomplete in many patients, and long-term sequelae are common [2020]. The reason to recognise it promptly is therapeutic: combined antiviral and corticosteroid treatment, started early, improves the odds of recovery.

CPost-viral and post-COVID tinnitus

Tinnitus can outlast the infection that triggered it. The COVID-19 pandemic brought this into focus: self-reported new or worsened tinnitus was reported by a meaningful proportion of people after SARS-CoV-2 infection, including in post-hospitalisation cohorts [2020]. A systematic review found audio-vestibular symptoms — hearing difficulty, tinnitus and dizziness — reported across multiple studies, though estimates were limited by self-report and study quality [2021].

The pandemic also exposed how powerfully context shapes tinnitus distress. Lockdown, isolation, anxiety, disrupted sleep and reduced access to care worsened the experience of pre-existing tinnitus even where the sound itself was unchanged [2020]. The clinical lesson generalises beyond COVID: any significant viral illness can act as a trigger or amplifier, and management blends audiological assessment with attention to mood, sleep and the surrounding life stress.