As vaccinations continue to roll out, it's beginning to look like a booster may be necessary for some COVID-19 vaccines.By Jessica Guay

PITTSBURGH (KDKA) – Around 6,000 Pennsylvanians received the second dose of the Pfizer vaccine at clinics held by Allegheny Health Network on Saturday.

Meanwhile, questions remain after Pfizer’s CEO said it is likely people will need more doses down the road.

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Allegheny Health Network held two second-dose vaccination clinics on Saturday. Organizers said around 4,500 doses were given at PNC Park and more than 1,000 shots were administered at Mount Ararat Baptist Church in East Liberty.

The patients were in Phase 1A and had pre-registered.

Dr. John Lee, AHN Chief Medical Information Officer, was assisting needs at PNC Park and said, “I haven’t had to address really any medical issues here, very few no-shows, and things are great.”

“I feel really good,” said Colleen Welsh right after getting her second Pfizer shot at PNC Park.

“I’m glad, I’m glad it’s over with. We’ll see what happens,” said Elisa Pengidore after getting her dose.

People may have to pull up their sleeves again to stay protected against COVID-19.

Pfizer’s CEO said a booster shot will likely be needed 6 to 12 months after getting fully vaccinated. It’s also possible people will need to get the vaccine yearly.

We heard mixed reactions from people at the PNC Park clinic.

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“I don’t know. I’m a little bit hesitant about that. Is it ever going to be over?” Pengidore said. “I’m not sure, let me get through this second one.”

“That’s no big deal. I mean growing up when I was younger, I had to get a couple of vaccinations, so I think it’s normal,” said Matthew Criste Makar at PNC Park.

“I don’t have a problem with it. It’s like getting a flu shot,” Welsh said.

Dr. Lee said the need for additional doses was expected and he compared it to the annual flu shot.

“Well, it’s for the same exact reason why we get an annual flu shot because the genetic sequence of influenza is different every year and the way that this virus is developing, it looks like it’s going to start developing different genetic shifts and mutations. It will likely require booster vaccinations on an ongoing basis,” Dr. Lee said.

Even though the virus may develop, health experts’ message stays the same.

“Just get vaccinated, don’t think about it twice,” said Dr. Lee.

AHN’s next vaccination clinic will be at Pittsburgh Mills on Tuesday, April 20.

Volunteers will administer up to 7,000 first doses of the Pfizer vaccine.

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Appointments are still available. You can register online at this link for their available clinics.