Guillain-Barré syndrome after vaccination against COVID-19.

Competing Interests: JYC, SP, JJ, T-SK, YJC, and H-SE declare no competing interests. J-WH has received a grant from the National Research Foundation of Korea. S-HK lectured for Bayer Schering Pharma, Genzyme, and Merck Seron; consulted for Bayer Schering Pharma, Merck Serono, Biogen, Genzyme, and Union Chimique Belge; received honoraria from Bayer Schering Pharma, Merck Serono, Genzyme, and UCB; and received a grant from the National Research Foundation of Korea. HJK received a grant from the National Research Foundation of Korea and research support from Aprilbio and Eisai; and received consultancy and speaker fees from Alexion, Aprilbio, Biogen, Celltrion, Daewoong, Eisai, GC Pharma, HanAll BioPharma, MDimune, Merck Serono, Novartis, Roche, Sanofi Genzyme, Teva-Handok, Union Chimique Belge, and Viela Bio. The Institutional Review Board of the National Cancer Center (IRB number NCC-2021–0260) approved this study and waived the requirement for informed consent because of the use of de-identified data. JYC and SP contributed equally as first authors.