Close to 2,000 people were inoculated at the site located at Soka University in Aliso Viejo. It opened its doors less than two weeks after the county's first large site opened at Disneyland.
The Disneyland site is outdoors, but vaccines at Soka University will be administered in the campus gymnasium. Residents may use the county's Othena app or website to make an appointment for either site.
Supervisor Lisa Bartlett said one advantage of the Soka University site is its convenience for seniors in the area such as residents of the Laguna Woods Village retirement community. County officials are providing vaccines for seniors 65 and older because they are among the most vulnerable to COVID-19.
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The county plans to open more sites once more vaccines are available.
Despite the opening of the new site, vaccine supply remains a major stumbling block for many Southern California counties. The Orange County Health Care Agency says it is continuously requesting more doses from the state.
Those who were able to get an appointment at the Aliso Viejo site said they are grateful for it reopening, including one woman who managed to get appointments for both her parents.
"I'm just so relieved because of everything that's been happening all over the world and just seeing all the people in the hospitals without their family members. I was so worried for my family but I'm so relieved," said Fatima Mougammadou.
She added that the process at the new site was very organized.
Even with the vaccine shortage, county officials say they believe they are on track to have everyone in Orange County vaccinated by the Fourth of July.
City News Service contributed to this report.