Robinson LB, Fu X, Hashimoto D, et al. - In this prospective cohort of almost 50,000 Mass General Brigham employees who received a messenger RNA (mRNA) COVID-19 vaccine, 1.9% self-reported cutaneous reactions after receiving the first dose.

• With inclusion of more than 600 employees with first-dose cutaneous reactions, no recurrent cutaneous reactions appeared in 83%.

• Cutaneous reactions occurred only after the second dose of the vaccine in an additional 2.3%.

• Women more frequently had development of cutaneous reactions, which was similar to reported local injection site reactions and anaphylaxis after mRNA COVID vaccinations.

• The most common cutaneous reactions were rash and itching (other than at the injection site).