Debes AK, Xiao S, Colantuoni E, et al. - The production of spike antibodies is induced by the two messenger RNA (mRNA) vaccines (Pfizer-BioNTech and Moderna) encoding the spike protein of SARS-CoV-2. Researchers herein examined a cohort of hospital workers (HWs) who received either mRNA vaccine and had known status of prior SARS-CoV-2 infection for their symptoms following vaccination and serum spike antibody levels with the aim to determine the differences in symptoms and serum immunoglobulin G (IgG) antibodies against S1 spike protein.

• A longitudinal study of S1 spike antibodies including HWs in the Johns Hopkins Health System. A total of 954 HWs were administered a questionnaire and provided serum samples 14 or more days following dose 2.

• Analysis revealed a strong antibody response to the spike protein in nearly 100% of HWs after dose 2 of the SARS-CoV-2 mRNA vaccine independent of vaccine-induced reactions.

• There was an association of clinically significant symptoms following dose 1 with prior SARS-CoV-2 infection, confirming prior reports.

• More frequently, dose 2 and receipt of the Moderna vaccine were linked with induction of clinically significant symptoms following vaccination.

• HWs who received the Moderna vaccine, had prior SARS-CoV-2 infection, and reported clinically significant reactions showed higher spike IgG antibody measurements.