Hearing loss in left ear; Tinnitus in left ear; This literature-study case was reported in a literature article and describes the occurrence of DEAFNESS UNILATERAL (Hearing loss in left ear) in a 48-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.   LITERATURE REFERENCE:  No Medical History information was reported.    On an unknown date, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On an unknown date, the patient experienced DEAFNESS UNILATERAL (Hearing loss in left ear) (seriousness criterion medically significant) and TINNITUS (Tinnitus in left ear). At the time of the report, DEAFNESS UNILATERAL (Hearing loss in left ear) and TINNITUS (Tinnitus in left ear) outcome was unknown.        The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.   For mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown), the reporter considered DEAFNESS UNILATERAL (Hearing loss in left ear) and TINNITUS (Tinnitus in left ear) to be possibly related.    In this case, patient had no prior hearing loss associated issues. The adverse effect was seen in left ear. The days to onset of symptoms was set as between 23 days.  Concomitant medications were not provided.    Most of the patients were still undergoing treatment, which may include oral, IT steroids, and/or antivirals. In all cases magnetic resonance imaging of the internal auditory canals was also ordered. The extent of hearing recovery and/or symptom resolution is currently unknown. Their pre-treatment audiograms, with the PTA and WRS recorded, have given them a good baseline with which to document any treatment effect, as well as review outcome versus specific treatment given, to be reported in the future. The extent of hearing recovery and/or symptom resolution is currently unknown.  Author concluded that currently, there are no known definite correlations between sudden hearing loss or other otologic manifestations with COVID-19 vaccination and that the clinic has noticed  a two-fold increase in diagnosis of idiopathic SNHL in a 30-day period in 2021 compared with the same interval 2 years ago, but cannot say if this specifically correlates to the pandemic or may represent an uncommon, but real AE not reported before this.  This case concerns a 48 year-old male patient with no reported medical history, who experienced the unexpected non-serious events of hearing loss in left ear and tinnitus. The events occurred an unknown number of days after the first dose of mRNA-1273 vaccine. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. Manual override done to remove seriousness criteria of Medically significant from event of Deafness unilateral based on medical judgement and review of source document that does not support seriousness criteria.   This case was linked to MOD-2021-337903, MOD-2021-337994, MOD-2021-337995, MOD-2021-337996, MOD-2021-337997, MOD-2021-337998, MOD-2021-337999, MOD-2021-338000, MOD-2021-338001, MOD-2021-338002, MOD-2021-338003, MOD-2021-338004, MOD-2021-338005, MOD-2021-338006, MOD-2021-338008, MOD-2021-338009, MOD-2021-338010 (Patient Link).; Sender's Comments: This case concerns a 48 year-old male patient with no reported medical history, who experienced the unexpected non-serious events of hearing loss in left ear and tinnitus. The events occurred an unknown number of days after the first dose of mRNA-1273 vaccine. The benefit-risk relationship of mRNA-1273 vaccine is not affected by this report. Manual override done to remove seriousness criteria of Medically significant from event of Deafness unilateral based on medical judgement and review of source document that does not support seriousness criteria.