Which Type of COVID-19 Vaccine Increases the Risk of GBS?

Several cases of Guillain-Barré syndrome (GBS) have been reported following administration of the adenoviral vector COVID-19 vaccines  ChAdOx1-s and Ad26.COV2.S. However, the risk associated with other vaccine types remains unclear due to mixed or limited data. To clarify these risks, a multinational study analyzed data from over 230 million individuals across 20 global sites assessing the risk of developing GBS within one to 42 days after receiving adenoviral vector, mRNA, and inactivated COVID-19 vaccines .

The study found that the adenoviral vector vaccine ChAdOx1-S/nCoV-19 was associated with an increased risk of GBS (relative incidence [RI]: 3.10). In contrast, decreased risks of GBS were observed following immunization with the mRNA vaccine BNT162b2 (RI = 0.48) and an inactivated vaccine (RI = 0.04). Additionally, SARS-CoV-2 infection itself was linked to a significantly increased…