The Virtua and FEMA site at the old Lord and Taylor at the Moorestown Mall is vaccinating thousands of patients daily and hit the milestone as New Jersey races to protect its residents against COVID-19.
Gabriela Peterman, a mother of three, was the 300,000th patient.
"I'm a lucky gal. I didn't know I was going to walk in here and be a certain number, but 300,000 vaccines is a lot of vaccines," she said.
The clinic can inoculate up to 6,000 people a day and staff have been working 12-hour days, seven days a week to vaccinate the community.
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"It's just another step closer to getting as many people as possible vaccinated," said Phyllis Worrell, the emergency management coordinator for Virtua who manages the site.
It's a race against infection rates as COVID cases are still spreading in New Jersey. As of Thursday, nearly 2,000 people were hospitalized in the state with the virus.
At the same time, nearly a third of New Jersey's eligible population is fully vaccinated.
"Every day that we are vaccinating we get to hear stories about how 95-year-old grandmas are going to get to hug their children or 16-year-olds are now going to be able to hug their grandparents," said Worrell.
For high school senior Jacqueline Chen, it also means she'll get to celebrate with her classmates.
"The good news is we're having an in-person prom and graduation, so that's something to look forward to," she said.
The clinic is offering only the Pfizer shot for now and has plenty of more appointments available. Staff does expect to resume one-shot Johnson & Johnson vaccinations this week as well now that the CDC and FDA have lifted the pause.