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SAN DIEGO — State health leaders are recommending vaccine providers stop using a batch of Moderna COVID-19 vaccines after a few suspected allergic reactions at a San Diego vaccination site.

The California Department of Public Health said fewer than 10 people sought medical care after getting vaccines from Moderna Lot 041L20A at Petco Park last week. San Diego County health officials confirmed a half-dozen healthcare workers suffered allergic reactions.

“All appeared to be experiencing a possible severe allergic reaction during the standard observation period – a type of adverse event that the CDC reports some people have experienced when receiving a COVID-19 vaccine. The vaccine site switched to another lot of Moderna vaccine after closing for a few hours,” the health department said in a news release Sunday.

The mass vaccination site at Petco Park opened on Jan. 11 with vaccines available to healthcare workers in the Phase 1A-Tier categories on California’s priority list.

Officials said more than 330,000 doses from the Moderna lot were distributed to 287 providers in California. Health leaders have not been notified of any other reactions related to the batch.

“Out of an extreme abundance of caution and also recognizing the extremely limited supply of vaccine, we are recommending that providers use other available vaccine inventory,” the news release said.

Moderna said in a statement that the company “is unaware of comparable adverse events from other vaccination centers which may have administered vaccines from the same lot.”

State health leaders said no vaccine or medical procedure is without risk and the chance of a serious adverse reaction is very small. While limited data exists on adverse reactions to the Moderna vaccine, a similar vaccine shows the expected rate of anaphylaxis is approximately 1 in 100,000, state health leaders said.

The manufacturer, CDC and FDA are reviewing the batch and related medical information. The state says they expect to learn more this week. Replacement doses are not immediately available during the pause.

The FDA previously noted side effects from the Moderna vaccine in a few trial participants who had cosmetic facial fillers in their cheeks and lips.

The state said providers of the COVID-19 vaccine should continue their routine precautions to recognize and manage allergic reactions and potential adverse events.