California is releasing hundreds of thousands of doses of coronavirus vaccine that it had put on pause Sunday after the vaccine batch was linked to a cluster of allergic reactions in San Diego last week.
The matter was examined by the state committee that reviews coronavirus vaccine safety and other agencies, according to state health officer Dr. Erica Pan.
“Yesterday, we convened the Western States Scientific Safety Review Workgroup and additional allergy and immunology specialists to examine the evidence collected,” the California Department of Public Health said in a statement Wednesday night. “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.”
The vaccines in question were from a batch of 330,000 Moderna vaccines that were sent to 287 health care providers in California earlier in January, and were halted Sunday because six health care workers who got the vaccine in San Diego last week apparently developed allergic reactions after receiving it. The six people were treated and have recovered.
No other allergic reactions have been reported from the batch other than the San Diego cluster.
Some vaccines in the batch had already been administered at the time of the pause, but it’s unclear exactly how many had been used. The suspension of the vaccines meant that a number of counties and providers had significantly fewer doses than they had been counting on.
San Francisco, for instance, received about 8,000 doses from the Moderna batch and had to stop administering them, which put the health department in a position to run out of vaccines by Thursday. Now that the state has allowed health care providers to resume using them, San Francisco would no longer be projected to run out of doses by Thursday.
Each batch, or lot, of vaccine is given a lot number from the manufacturer. The vaccines in question were from lot number 41L20A.
Severe allergic reactions from vaccines are very rare. There is no data on how many allergic reactions have occurred from the Moderna vaccine. But for a similar coronavirus vaccine, made by Pfizer, the risk is about 1 in 100,000.
The state said the 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.”
Catherine Ho is a San Francisco Chronicle staff writer. Email: [email protected] Twitter: Cat_Ho