covid-19 A Nation in Crisis: Peru's COVID-19 Nightmare Intensifies with Guillain-Barre Syndrome Outbreak Several studies have indicated a potential association between specific COVID-19 vaccines, including Ad26.COV2.S (Janssen), BNT162b2 (Pfizer-BioNTech), and mRNA-1273 (Moderna), and GBS. Nevertheless, the overall risk of developing GBS following COVID-19 vaccination appears to be extremely low.