Illustration by Daniel Schludi on Unsplash.



Three days after the state placed a pause on administering 330,000 doses of Moderna’s COVID-19 vaccine due to reports of allergic reactions, California Public Health officials have announced that there is “no scientific basis to continue the pause.”

The previously suspect lot, Moderna 041L20A, represented a week’s worth of doses for the state. Humboldt County Public Health had 4,100 doses of that batch in its freezer and had already administered some doses to local residents, according to Public Heath Officer Dr. Ian Hoffman

California State Epidemiologist Dr. Erica Pan issued the following statement late Wednesday, advising providers that they can immediately resume use of the vaccine:

Our highest priorities are to ensure that vaccines are safe and effective, and distributed equitably and efficiently.

Out of an abundance of caution, we recommended that providers pause the distribution of Moderna COVID-19 vaccine lot 41L20A on Sunday evening. Yesterday, we convened the Western States Scientific Safety Review Workgroup and additional allergy and immunology specialists to examine the evidence collected. We had further discussions with the County of San Diego Department of Public Health, the FDA, CDC and manufacturer, and found no scientific basis to continue the pause. Providers that paused vaccine administration from Moderna Lot 41L20A can immediately resume.

These findings should continue to give Californians confidence that vaccines are safe and effective, and that the systems put in place to ensure vaccine safety are rigorous and science-based. Members of my family who have qualified to receive the vaccine as health care workers or because of their age have already received the COVID-19 vaccine, and I encourage every Californian to get the vaccine when it’s their turn.

View the workgroup’s summary of findings.