Incidence of Guillain-Barré Syndrome (GBS) after COVID-19 Vaccination: a Systematic Review and Meta-Analysis.

Background: Global vaccination against COVID-19 will help nations to overcome the pandemic stage as soon as possible. Guillain-Barré syndrome (GBS) is an acute immune-mediated inflammatory disease of the peripheral nerves (PNS) that is reported as a complication of both COVID-19 and vaccines. Up to now, case reports regarding the incidence of GBS have been reported after different COVID-19 vaccines worldwide. So, the aim of this systematic review and meta-analysis is to estimate the pooled incidence of GBS after COVID-19 vaccination.
Methods: Two expert researchers conducted a systematic search in PubMed, Scopus, EMBASE, Web of Science, Google Scholar as well as gray literature in order to find relevant articles published before September 2022.
Results: After deleting duplicates, we found 1021 articles, of which 458 studies were further evaluated. A final number of 21 studies remained for meta-analysis, with most of those being from the USA, UK and Mexico. Follow-up duration was between 21-42 days. Out of the total number of 2.35x109 patients included in the final meta-analysis, 3654 subjects developed GBS after vaccination, most of whom were males. Incidence of GBS per million ranged between 0.23 and 9.8. The pooled incidence of GBS following vaccination was 0%.