Incidence of Guillain-Barré syndrome following SARS-CoV-2 immunization: Analysis of a nationwide registry of recipients of 81 million doses of seven vaccines

Abstract

Background and purpose: Information on Guillain-Barré syndrome (GBS) as an adverse event following immunization (AEFI) against SARS-CoV-2 remains scarce. We aimed to report GBS incidence as an AEFI among adult (≥18 years) recipients of 81,842,426 doses of seven anti-SARS-CoV-2 vaccines between December 24, 2020, and October 29, 2021, in Mexico.

Methods: Cases were retrospectively collected through passive epidemiological surveillance. The overall observed incidence was calculated according to the total number of administered doses. Vaccines were analyzed individually and by vector as mRNA-based (mRNA-1273 and BNT162b2), adenovirus-vectored (ChAdOx1 nCov-19, rAd26-rAd5, Ad5-nCoV, and Ad26.COV2-S), and inactivated whole-virion-vectored (CoronaVac) vaccines.

Results: We identified 97 patients (52 males [53.6%]; median [interquartile range] age 44 [33-60] years), for an overall observed incidence of 1.19/1,000,000 doses (95% confidence interval [CI] 0.97-1.45), with incidence higher among Ad26.COV2-S (3.86/1,000,000 doses, 95% CI 1.50-9.93) and BNT162b2 recipients (1.92/1,00,000 doses, 95% CI 1.36-2.71). The interval (interquartile range) from vaccination to GBS symptom onset was 10 (3-17) days. Preceding diarrhea was reported in 21 patients (21.6%) and mild COVID-19 in four more (4.1%). Only 18 patients were tested for Campylobacter jejuni (positive in 16 [88.9%]). Electrophysiological examinations were performed in 76 patients (78.4%; axonal in 46 [60.5%] and demyelinating in 25 [32.8%]); variants were similar across the platforms. On admission, 91.8% had a GBS disability score ≥3. Seventy-five patients (77.3%) received intravenous immunoglobulin, received seven plasma exchange (7.2%), and 15 (15.5%) were treated conservatively. Ten patients (10.3%) died, and 79.1% of survivors were unable to walk independently.

Conclusions: Guillain-Barré syndrome was an extremely infrequent AEFI against SARS-CoV-2. The protection provided by these vaccines outweighs the risk of developing GBS.

Keywords: COVID-19; Guillain-Barré syndrome; SARS-CoV-2; Vaccines; adverse events.

FIGURE 1

Patient selection flowchart. AEFI, adverse event following immunization; GBS, Guillain–Barré syndrome

FIGURE 2

Time from the last administered dose to Guillain–Barré symptom onset according to vaccine platform. The figure shows that when cases were analyzed according to the time from the last administered dose, Guillain–Barré symptoms occurred most commonly within the first week after vaccination. Inactivated virus includes CoronaVac; adeno‐vector includes ChAdOx1 nCov‐19, rAd26‐rAd5, Ad5‐nCoV, and Ad26.COV2‐S; mRNA‐based includes mRNA‐1273 and BNT162b2. *Represents 5.9% of cases occurring during Days 15 to 21 after immunization. **Represents 6.3% of cases occurring during ≥22 days after immunization

FIGURE 3

Incidence ratio of Guillain–Barré syndrome according to vaccine subtype and platform. This figure shows that when using CoronaVac (inactivated virus vaccine) as a reference value, incidences were higher for Ad26.COV2‐S, BNT162b2, and mRNA‐based vaccine recipients. (a) Incidence ratio according to vaccine subtype. (b) Incidence ratio according to vaccine platform. All calculations were made using CoronaVac, an inactivated virus single‐dose regimen vaccine as the reference. *Reference vaccine and platform value