Klein NP, Lewis N, Goddard K, et al. - Researchers monitored 23 serious outcomes weekly following receipt of mRNA COVID-19 vaccines in order to determine if the vaccines are linked with elevated risk for serious health outcomes during days 1 to 21 after vaccination.

• Using comprehensive health records on a diverse population, researchers conducted an interim analysis of safety surveillance data from 6.2 million persons who received 11.8 million doses of an mRNA vaccine.

• No significantly higher event rates were recorded for 23 serious health outcomes among individuals for 1 to 21 days after vaccination when compared with similar individuals at 22 to 42 days after vaccination.

• Overall, vaccination with mRNA COVID-19 vaccines did not link significantly with selected serious health outcomes 1 to 21 days after vaccination, although wide CIs were recoded for some rate ratio estimates and additional follow-up is ongoing.