Risk of Guillain-Barré syndrome after COVID-19 vaccination or SARS-CoV-2 infection: a multinational self-controlled case series study

Background — The association between Guillain-Barré syndrome (GBS) and certain COVID-19 vaccines is inconclusive. We investigated the risk of GBS after COVID-19 vaccination or SARS-CoV-2 infection.

Methods — Using a common protocol, we conducted a self-controlled case series study from 1 December 2020 to 9 August 2023 at 20 global sites within the Global Vaccine Data Network™ (GVDN®). Brighton Collaboration case definition criteria were used to determine the level of certainty (LOC) of medical record-reviewed GBS cases at 15 sites. GBS cases following SARS-CoV-2 infection were identified from electronic data sources (EDS) from 11 sites. We estimated the relative incidence (RI) of GBS within 1–42 days following receipt of adenoviral vector, mRNA, or inactivated COVID-19 vaccines or SARS-CoV-2 infection using conditional Poisson regression models, controlling for seasonality. We used random effects meta-analysis to pool the estimates across sites.

Results — Of 410 medical record-reviewed post-vaccination GBS cases (out of 2086 EDS-identified cases), 49 were LOC 1 or 2, 187 were LOC 3 or 4, and 174 were LOC 5. These cases received a total of 794 doses of COVID-19 vaccines (160 [20 %] adenoviral vector vaccine doses, 556 [70 %] mRNA vaccine doses, 77 [10 %] inactivated vaccine doses, and 1 [0.1 %] protein-based vaccine dose) during the observation period. We observed an increased risk of confirmed (LOC 1–2) GBS after receiving ChAdOx1-S/nCoV-19 (Vaxzevria/Covishield) (RI = 3.10; 95 % confidence interval [CI], 1.12–8.62). Decreased risks of LOC 1–4 GBS were observed after receiving BNT162b2 (Comirnaty/Tozinameran) (RI = 0.48; 95 %CI, 0.27–0.85) and CoronaVac/Sinovac (RI = 0.04; 95 %CI, 0.00–0.61). For 489 EDS-identified GBS cases after SARS-CoV-2 infection, we found GBS risk to be increased (RI = 3.35; 95 %CI, 1.83–6.11).

Conclusion — In this large multinational study, we found increased risks of GBS within 42 days after Vaxzevria/Covishield vaccination or SARS-CoV-2 infection, and decreased risks after receiving Comirnaty/Tozinameran or CoronaVac/Sinovac COVID-19 vaccines.