Delayed Local Reactions to mRNA-1273 Vaccination Reported

FRIDAY, March 5, 2021 (HealthDay News) — Twelve cases of delayed large local reactions to the mRNA-1273 vaccination against severe acute respiratory syndrome coronavirus 2 are described in a letter to the editor published online March 3 in the New England Journal of Medicine.

Kimberly G. Blumenthal, M.D., from Massachusetts General Hospital in Boston, and colleagues describe a series of 12 patients with delayed large local reactions to the mRNA-1273 vaccine at a median onset of day 8 after the first dose.

The researchers report that the reactions appeared near the injection site after complete resolution of the initial local and systemic symptoms associated with vaccination. Five reactions were grade 3 plaques (≥10 cm in diameter). Concurrent systemic adverse effects were reported for some patients, and of these, two had additional skin findings. Treatment of symptoms was provided for most patients (e.g., ice and antihistamines); some received glucocorticoids; and one patient received antibiotic therapy for presumptive cellulitis. Symptom resolution occurred at a median of six days after onset. All 12 patients were encouraged to receive the second dose of the mRNA-1273 vaccination course. Six patients did not have recurrence, while three had recurrent reactions that were similar to those after the initial dose and three had recurrent reactions that were of a lower grade.

“Our immediate goal is to make physicians and other care providers aware of this possible delayed reaction, so they are not alarmed, but instead well informed and equipped to advise their patients accordingly,” Blumenthal said in a statement.

Several authors disclosed financial ties to the biopharmaceutical and medical technology industries.

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