California official calls for pause on Moderna vaccine lot after possible allergic reaction
Dr. Erica S. Pan, the California epidemiologist, issued a statement Sunday recommending a pause in the distribution of a specific lot of Moderna vaccine after "fewer than 10 individuals required medical attention over the span of 24 hours."

She said the Moderna Lot 041L20A is in question, but she insisted that she called for the pause "out of an extreme abundance of caution," according to Fox 11.

The report said more than 330,000 doses from the lot already have been distributed throughout the state to 287 providers. Fox 5 San Diego reported that the California Department of Public Health said fewer than 10 people appeared to be experiencing "a possible severe allergic reaction during the standard observation period" following the vaccinations at Petco Park.

Comment: It's highly likely that some of the side effects will only become apparent after the 'standard observation period'.

The statement said that Moderna, the CDC and the FDA are all looking into the batch and said no vaccine or medical procedure is without risk. Moderna did not immediately respond to an after-hours email from Fox News.

The Moderna vaccine is very similar to one from Pfizer Inc. and Germany's BioNTech that's now being dispensed to millions of health care workers and nursing home residents.

NIH Director Dr. Francis Collins told the Associated Press in December that the two vaccines work "better than we almost dared to hope."