Reports of Allergic Reactions to Moderna Vaccine

Jan 21, 2021 — California’s top epidemiologist late Wednesday said the Moderna vaccine suspected of causing a series of allergic reactions may be administered once again after a review found no reason to stop its use.

Erica Pan, MD, said the state had temporarily paused the use of one lot of Moderna’s vaccine after reports that some employees at a San Diego vaccination center required medical attention after they were vaccinated, Moderna said in a statement.

“Moderna acknowledges receiving a report from the California Department of Public Health that several individuals at one vaccination center in San Diego were treated for possible allergic reactions after vaccination from one lot of Moderna’s COVID-19 Vaccine,” the company said.

Moderna said Tuesday it was cooperating with CDPH in the investigation and doesn’t know of “comparable clusters of adverse events” from other vaccination centers using vaccine from that lot.

Pan recommended providers temporarily stop giving Moderna vaccine from lot No. 041L20A until the state, the CDC, the FDA, and Moderna could investigate what happened.

Now, she says, that lot of doses may be used.

“Yesterday, we convened the Western States Scientific Safety Review Workgroup and additional allergy and immunology specialists to examine the evidence collected,” Pan said in a statement. “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.”

Pan said fewer than 10 people required medical attention during a 24-hour period after receiving the vaccine from that lot at one community site. KTGV-TV reported that six health care workers had allergic reactions to vaccines at the Petco Park vaccination center on Jan. 14.

The CDPH said about 330,000 doses from that lot went to 287 providers across the state after being shipped Jan. 5-12. No other allergic reactions were reported, the CDPH said. More than 307,000 doses remain in storage.

Moderna said the lot contained 1,272,200 doses and that about 1 million doses have been distributed to 1,700 vaccination sites in 37 states. The company said it doesn’t know how many doses from the lot have been given to people.

The coronavirus vaccines from Moderna and Pfizer/BioNTech are the only ones now being administered in the United States.