Dr. Thomas Farley made the announcement Friday that Philadelphia would expand vaccine eligibility earlier than expected because not enough people were signing up.
"We are entering a new phase now to where the people who are left unvaccinated are maybe not as eager as the people who have already been vaccinated," Farley said.
Monday was the first day for New Jersey and there was a steady stream of people at Rowan College's mass vaccination clinic. After leaving the clinic partially vaccinated, Nina Munciello - a high school senior - said that after losing her senior year she is optimistic again.
"Finally, I feel like I can go out and feel safer," she said.
In Philadelphia, both FEMA-run sites at the Convention Center and Esperanza again offered walk-up appointments.
In addition, several city-run sites will offer "Walk-up Wednesdays" for seniors over 65. Currently, there are 260 city sites.
With so many people now eligible for shots, officials want to make sure people are filling up the once hard-to-secure appointments.
In Aston, Delaware County on Monday, the county site went hybrid offering both appointments and walk-ups.
"We're looking for about 200 walk-ups in addition to our 900," said Dennis Daye, the Volunteer Coordinator at the Aston site.
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"We still need to fill the available slots so more people can be vaccinated," said Howard Lazarus, the Delaware County Executive Director.
Across the tri-state area, officials hope walk-up appointments help fill the gaps and are a solution to the "digital divide," which often leaves out seniors and those who do not have internet access.
Lazarus also said they are in discussions to figure out how to best vaccinate young adults and children when that time comes.
"The school district has a plan also to vaccinate 16-18 year olds over the summer months as soon as vaccines are approved for pediatric use. We'll work with them on 12-16 year olds," he said.