A pharmacist discovered Tuesday night that a refrigeration unit at the Soka University site holding vials of the Pfizer vaccine was operating slightly outside the recommended temperature range.
That triggered precautionary measures as the site set aside the day's supply of doses. For much of the day Wednesday it remained unclear whether some or all of that day's supply would have to be discarded.
The Aliso Viejo site normally dispenses about 3,000 doses of vaccine a day.
That was particularly concerning at a time when vaccine supplies remain limited and in high demand as the coronavirus continues to infect thousands of people every day throughout California - and as new, more contagious variants become more prevalent in the state.
But by late in the day came news that brought a sigh of relief: After consulting with the manufacturer, they determined the refrigeration issue was not enough to harm the doses and they could still be distributed.
"After reviewing the details, the manufacturer advised that the temperature variance did not harm the vaccine's safety or efficacy and provided confirmation that the vaccine is safe to dispense under the normal protocol," county officials said in a written statement.
While the doses in question had been set aside, additional doses had been brought in and all of the scheduled appointments were honored, officials said.
The Soka site, which opened Jan. 23, is what the county refers to as a super POD or point of dispensing, capable of thousands of appointments in a single day.
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As of data from last week, the county had administered first doses of vaccine to more than 196,000 people and second doses to about 46,000.
Vaccination information and appointment scheduling for Orange County are available here at Othena.com.