Delayed Large Local Reactions to mRNA-1273 Vaccine against SARS-CoV-2
Kimberly G. Blumenthal, Esther E. Freeman, Rebecca R. Saff, Lacey B. Robinson, Anna R. Wolfson, Ruth K. Foreman, Dean M. Hashimoto, Aleena Banerji, Lily Li, Sara Anvari, Erica S. Shenoy
Abstract
Vaccine against SARS-CoV-2To the Editor: Baden et al. 1 report on a phase 3 clinical trial of the mRNA-1273 vaccine against SARS-CoV-2, and they provide information on immediate injection-site reactions, which were observed in 84.2% of the participants after the first dose.The trial also showed that delayed injection-site reactions (defined in that trial as those with an onset on or after day 8) occurred in 244 of the 30,420 participants (0.8%) after the first dose and in 68 participants (0.2%) after the second dose.These reactions included erythema, induration, and tenderness.The reactions typically resolved over the following 4 to 5 days.However, these reactions were not further characterized, and links between reactions after the first dose and those after the second dose were not provided to inform clinical care.We have also observed delayed large local reactions to the mRNA-1273 vaccine, with a median onset on day 8 (range, 4 to 11) after the first dose.These reactions had a variable appearance (Fig. 1).Here, we report on a series of 12 patients with these reactions, all of which appeared near the injection site after complete resolution of the initial local and systemic symptoms associated with vaccination.Five of the reactions were grade 3 plaques (≥10 cm in diameter) (Table 1).Some patients had concurrent systemic adverse effects, and among these patients, 2 had additional skin findings.Most patients received treatment for their symptoms (e.g., with ice and antihistamines).Some patients received glucocorticoids (topical, oral, or both), and 1 patient received antibiotic therapy for presumptive cellulitis.The symptoms resolved a median of 6 days after onset (range, 2 to 11).Our suspicion of delayed-type or T-cell-medi-Downloaded from nejm.org