tetano
Editor, Senior Moderator
J Allergy Clin Immunol Glob
. 2025 Nov 29;5(2):100620.
doi: 10.1016/j.jacig.2025.100620. eCollection 2026 Mar.
COVID-19 mRNA revaccination is safe and well tolerated in individuals with previous adverse reactions to the vaccine and/or long COVID
Ian F Slack[SUP] 1 2 [/SUP], Kelly M O'Shea[SUP] 1 2 [/SUP], George E Freigeh[SUP] 1 3 [/SUP], Lea M Franco[SUP] 2 [/SUP], Sara Jaafar[SUP] 2 [/SUP], Charles F Schuler 4th[SUP] 1 2 [/SUP], James R Baker Jr[SUP] 1 2 4 [/SUP]
Affiliations
Background: Vaccine safety is a primary concern among those with a history of adverse reactions to coronavirus disease 2019 (COVID-19) mRNA vaccines. Retrospective data and cohorts of individuals with severe previous reactions suggest that revaccination is safe and well tolerated. However, prospective data are limited.
Objective: We sought to prospectively assess safety and tolerability of COVID-19 mRNA vaccines in individuals with a history of adverse vaccine reactions and in individuals with long COVID.
Methods: Adults with a self-reported adverse reaction to COVID-19 mRNA vaccination and/or long COVID underwent COVID-19 mRNA revaccination at the University of Michigan with 30-minute observations. Participants were contacted by telephone after 7 days to review interval adverse events.
Results: A total of 103 participants received COVID-19 mRNA revaccination-91 with history of adverse vaccine reaction, 20 with long COVID, and 8 with both. Mean age at enrollment was 41.8 years, and women were 67% of the cohort. Five individuals (4.9%) developed immediate symptoms with revaccination. All 5 events were mild (Consortium for Food Allergy Research severity level 1). Vital signs were assessed prevaccination and 30 minutes postvaccination. At 7-day follow-up, 77% of participants reported at least 1 adverse event, with fatigue (33.7%), headache (29.7%), and muscle pain (28.7%) most commonly reported. No follow-up reactions were severe. Five of the 103 participants had incidentally elevated baseline serum tryptase. None of these participants experienced immediate symptoms with revaccination.
Conclusions: Revaccination with COVID-19 mRNA vaccines was safe and well tolerated among individuals with previous adverse COVID-19 mRNA vaccine reaction and/or long COVID.
Keywords: COVID-19; SARS-CoV-2; adverse reaction; mRNA vaccine; revaccination; tryptase.
. 2025 Nov 29;5(2):100620.
doi: 10.1016/j.jacig.2025.100620. eCollection 2026 Mar.
COVID-19 mRNA revaccination is safe and well tolerated in individuals with previous adverse reactions to the vaccine and/or long COVID
Ian F Slack[SUP] 1 2 [/SUP], Kelly M O'Shea[SUP] 1 2 [/SUP], George E Freigeh[SUP] 1 3 [/SUP], Lea M Franco[SUP] 2 [/SUP], Sara Jaafar[SUP] 2 [/SUP], Charles F Schuler 4th[SUP] 1 2 [/SUP], James R Baker Jr[SUP] 1 2 4 [/SUP]
Affiliations
- PMID: 41550084
- PMCID: PMC12803966
- DOI: 10.1016/j.jacig.2025.100620
Background: Vaccine safety is a primary concern among those with a history of adverse reactions to coronavirus disease 2019 (COVID-19) mRNA vaccines. Retrospective data and cohorts of individuals with severe previous reactions suggest that revaccination is safe and well tolerated. However, prospective data are limited.
Objective: We sought to prospectively assess safety and tolerability of COVID-19 mRNA vaccines in individuals with a history of adverse vaccine reactions and in individuals with long COVID.
Methods: Adults with a self-reported adverse reaction to COVID-19 mRNA vaccination and/or long COVID underwent COVID-19 mRNA revaccination at the University of Michigan with 30-minute observations. Participants were contacted by telephone after 7 days to review interval adverse events.
Results: A total of 103 participants received COVID-19 mRNA revaccination-91 with history of adverse vaccine reaction, 20 with long COVID, and 8 with both. Mean age at enrollment was 41.8 years, and women were 67% of the cohort. Five individuals (4.9%) developed immediate symptoms with revaccination. All 5 events were mild (Consortium for Food Allergy Research severity level 1). Vital signs were assessed prevaccination and 30 minutes postvaccination. At 7-day follow-up, 77% of participants reported at least 1 adverse event, with fatigue (33.7%), headache (29.7%), and muscle pain (28.7%) most commonly reported. No follow-up reactions were severe. Five of the 103 participants had incidentally elevated baseline serum tryptase. None of these participants experienced immediate symptoms with revaccination.
Conclusions: Revaccination with COVID-19 mRNA vaccines was safe and well tolerated among individuals with previous adverse COVID-19 mRNA vaccine reaction and/or long COVID.
Keywords: COVID-19; SARS-CoV-2; adverse reaction; mRNA vaccine; revaccination; tryptase.