The Keystone State is opening up eligibility to Pennsylvanians 65 and older and those 16 and older with high-risk medical conditions.
"There are more than 3.5 million Pennsylvanians that are now in Phase 1a of our vaccine plan. We must have patience," said Deputy Heath Secretary Cindy Findley.
The state has launched a "vaccine eligibility quiz" with a map to find providers and discourage those who are not eligible to wait their turn.
SEE ALSO: Pennsylvania and Philadelphia officials expand COVID-19 vaccine distribution
Philadelphia is doing things a bit differently by design and will begin vaccinations for residents 75 and older and those with certain medical conditions.
"Our priority scheme was developed in part because we recognize an awful lot of people who are at risk in Philadelphia do have these chronic medical conditions," said Philadelphia Health Commissioner Dr. Thomas Farley.
City health officials acknowledged their system would be different from the suburbs where they're not spared the woes of supply and demand either.
"We were not expecting the huge addition of literally millions of people across Pennsylvania," said Bucks County spokesperson Larry King.
So, places like Bucks County, currently the fifth-largest in terms of vaccine distribution statewide, is working to expand vaccination.
SEE ALSO: Penn doctor says COVID-19 vaccine benefits being undersold
The Garden State, which expanded the pool of those eligible for a vaccine last week, is nearing 400,000 vaccinations.
With the infrastructure in place for mass inoculations, the governor is counting on the incoming Biden administration to help fill them.
"All that we are currently missing are the doses of vaccines necessary for us to put this machinery into high gear," said Governor Phil Murphy.
To support their expanded vaccination efforts of some 200,000 residents, Delaware is launching an online appointment system, starting with those 65 and older to get vaccinated at a state-run site.
"This is going to be my top priority to make sure we get on the other side of this," said Governor John Carney.
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