The goal of this study is to compile published data reporting neurological immune-related adverse events following COVID-19 vaccination, not including those relating to hematologic abnormalities such as thrombosis or hemorrhage.

COVID-19 vaccination has been repeatedly shown to reduce the incidence and severity of COVID-19 infection. The expedited timeline of these vaccines has given rise to many discussions pertaining to their safety. Many neurological and non-neurological adverse events have been linked to COVID-19 vaccination including acute MI, anaphylaxis, appendicitis, Bell’s palsy, deep vein thrombosis, disseminated intravascular coagulation, encephalomyelitis, transverse myelitis, and many others.

The following databases were searched in April 2021 using different keywords: PubMed, Medline, Embase, Scopus, Web of Science, Science, Direct, MedRxiv, and Lens.org. Studies were included if they reported any adverse immune-related neurological events secondary to COVID-19 vaccination. Studies were excluded if they were not in English, included self-reported events only, or did not report primary data. Screening and extraction were conducted by 2 different reviewers using Covidence.

The search strategy yielded 18 studies which reported a total of 61 patients who had received a COVID-19 vaccination and experienced ≥ 1 neurological adverse events. Most reported adverse events were facial nerve palsy (52.5%), reactivation of herpes zoster (11.5%), Guillian-Barré syndrome (6.6%), demyelinating disease (6.6%), and neuropathy (11.5%). Other reported adverse effects were delirium, periauricular vesicular rash, bilateral sensorineural hearing loss, visual disturbance, gait disturbance, serotonin syndrome, and vestibular ataxia (16.4%).

The symptoms were time-limited and self-resolving in nature. In addition, the incidence of the reported events following COVID-19 vaccination compared to the general population is similar. Hence, there is little to no evidence suggesting a causal relationship between COVID-19 vaccination and neurological adverse events.