Hundreds of thousands of COVID-19 vaccines haven’t been used in Pa. and N.J. Here’s why, and what’s next.

Pennsylvania and New Jersey have received almost 1.4 million doses of coronavirus vaccine, but hundreds of thousands of the shots had not been used as of Friday, making for a slow first four weeks of the long-awaited rollout.

As questions abound about how long it will be before the vaccine is widely available — only health-care workers and nursing home residents are eligible right now — and the death toll climbs here and nationwide, some of the doses that have already made it to the states seem to have gotten stuck in the wings.

Less than a third of doses delivered to Pennsylvania and New Jersey had been administered, according to data from the Centers for Disease Control and Prevention, although officials in both states say the tally is undercounted due to reporting lags and say their pace is already accelerating.

Friday brought signs that the effort was ramping up as promised: In the first three weeks of vaccine distribution, more than 160,000 doses were reported to have been administered in Philadelphia and Pennsylvania. By Friday, that number had increased by about 110,000.

“Standing up this complex new program, right at [the holidays], posed a challenge,” Pennsylvania Health Secretary Rachel Levine said Thursday. “Pennsylvania and all [the states] are gearing up this week and … I think this program is going to gear up and roll out really well.”

The states’ health leaders don’t dispute, though, that a significant number of doses shipped to hospitals, pharmacies, and health centers have not yet been used, with reasons ranging from the unique and unprecedented nature of this pandemic and the enormous complications of administering a highly perishable vaccine to health-care workers’ reluctance to trust the vaccine.

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Pennsylvania and New Jersey health officials detailed logistical roadblocks in interviews with The Inquirer and at news briefings this week. Hospital leaders in the region also offered a window into the challenges playing out as health-care workers try to get the shots into the public’s arms.

New Jersey has set a goal to give 67,000 to 80,000 shots a day, but Pennsylvania officials couldn’t say what their target is. At the current rate, getting a first dose to enough Pennsylvanians to approach herd immunity, not including Philadelphia, will take almost 2½ years, an Inquirer data analysis shows.

“It’s really hard to set a goal when there’s so many unknowns related to how we would meet that goal,” said Pennsylvania Department of Health spokesperson Rachel Kostelac. “We are building a road map to vaccinate as many Pennsylvanians as is safely possible at any given time, but while we’re building that road map, we’re also building the road simultaneously.”

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The challenges are being reported across the country: Fewer than a third of shots shipped across the United States have actually been administered, according to the CDC, though the numbers are slightly undercounted because of delays in reporting.

As of Friday, 6.7 million people in the United States had received their first shots — a far cry from the 20 million the federal government said by the end of 2020.

“There’s a lot of interest about the pace of distribution of vaccines across the country, I think in part because the federal government set expectations that were unreasonably high,” Philadelphia Health Commissioner Thomas Farley said. “We would like to have more vaccines in people’s arms right now, but we’re doing the best we can.”

The vaccine promises to bring relief to a tragic year that has seen more than a million infected and more than 34,000 killed in Pennsylvania and New Jersey. But health officials have warned for weeks that the limited supply of the two vaccines, made by Pfizer-BioNTech and Moderna, would mean weeks of waiting for many as the states vaccinate the population in phases.

While most local and state officials, including Levine, say the biggest challenge will be getting enough doses made and distributed to vaccinate the majority of Americans, the challenges to using the doses that have already arrived in the states are a little more complex.

Difficult delivery, staffing, scheduling, storage and handling requirements, and pandemic-related constraints make inoculations much harder than simply putting up a tent, inviting in the crowds, and jabbing arm after arm. Plus, a lack of funding hampered state health departments, officials said, while hospitals are strained by vaccinating staff even as they have responded to the fall-winter surge in COVID-19 cases.

Starting during the holidays also “posed a significant limitation,” and it has been hard to predict exactly how many doses will arrive from the federal government each week, Levine told reporters on a call Thursday.

She stressed that the pace would speed up and said this week that the state was not behind in its rollout to health-care workers and nursing home residents.

“My expectation would be if you roll this forward a month, you’ll have more vaccines in distribution, you’ll have more people being vaccinated, and the process itself will work out some of those kinks,” said Steve Tracey, executive director for Center Supply Chain Research at Pennsylvania State University. “I’d say it’s probably going as well as should be expected.”

Experts said better planning at the federal level, including stronger guidance for states and more funding, could have improved the rollout. Leaving so much up to the states — as the Trump administration has done since the beginning of the pandemic — has “resulted in a pluperfect disaster,” said William Schaffner, professor of infectious diseases at the Vanderbilt University Medical Center, because each state has been free to develop its own distribution priorities, some wildly different from others. Meeting such varied demands creates logistical nightmares, he said.

The CDC did not reply to questions Friday.

About one million people in Pennsylvania are eligible to be vaccinated in the first phase, the state says, plus up to 130,000 in Philadelphia. As of Tuesday, about a quarter of a million people had been vaccinated statewide. New Jersey has received more than 572,000 doses and administered more than 155,000, although Health Commissioner Judith Persichilli said this week that state officials believe the number to be a “significant” undercount.

Most states have distributed a roughly similar number of first doses per capita, according to the CDC, though some are lagging more and others performing better.

Philadelphia, in fact, is performing better than most large cities. The city has vaccinated almost 2,000 people per 100,000 as of Jan. 5, an Inquirer analysis found, a better rate than in New York, Chicago, Los Angeles, and Houston.

Still, unless shipments speed up, it will take more than a year to vaccinate everyone in Philadelphia, Farley said.

Those administering the vaccine are engaged in a balancing act. They have to weigh their supply with estimates of the number of people to be vaccinated each day, try to ensure they have enough to meet their vaccination schedule, and provide second doses on time for the people who have received their first shot. (To complicate matters, the Pfizer vaccine, once processed for injection, is viable only for six hours.)

“I’m careful not to overcommit,” said Tony Reed, chief medical officer for Temple University Health System. “The last thing I want to do is have someone sitting there with their sleeve rolled up and say, ‘Sorry, I have no vaccine left.’”

And giving out the vaccine requires the availability of staff — often at hospitals already strained by the pandemic. At Einstein Medical Center Philadelphia, vaccination sites include five people doing injections, two people gathering information from those getting shots, two greeters — one to take temperatures and another doing crowd control — and a manager, along with pharmacy personnel, president Steven Sivak said.

In addition, some vaccine providers have not started giving out doses they’ve received because they’re still preparing, said Cindy Findley, who is overseeing Pennsylvania’s vaccine rollout for the Department of Health. And all providers are now required to keep at least 10% of the doses they receive in reserve for health-care workers not affiliated with hospitals.

Reluctance to take the vaccine also accounts for some of the unused doses, whether due to health-care workers’ unwillingness to risk side effects — which are generally mild — over the holidays, or some people’s distrust of the vaccine, which was developed in less than a year.

Even though the vaccines have been produced at record speed, they have been tested on thousands of people in clinical trials, and approved by the Food and Drug Administration for most people over age 16.

Neither New Jersey nor Pennsylvania said exactly how much hesitancy to take the vaccine contributed to the number of unused doses, but both mentioned it as a factor. Persichilli mentioned that there was more resistance in South Jersey than in the northern part of the state.

Hospitals locally have had workers wary of receiving shots.

“I had a small handful of people who in the first couple of weeks said, ‘I want to wait until mid-January,’” said Reed of Temple. “Is that because of the holidays, [or] mistrust … I’m not going to push and pry.”

Temple is going department by department to encourage workers to be vaccinated, though hospital officials have not said they will make vaccination mandatory.

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“We want everybody to feel like they should and can get this,” Reed said.

As more people get the vaccine, Persichilli said, concerns will likely fade: Last week, a survey of New Jersey residents found 60% were willing to take the vaccine, compared with 40% in November.

Health officials acknowledge the current rate of vaccination must improve, but Pennsylvania wouldn’t be specific about what its target is. New Jersey, though, said typically if a facility giving injections doesn’t get through 65% of its supply each week, the state Health Department calls to find out why some doses weren’t used.

For the state to accelerate its own distribution to vaccine providers, it needs more doses, officials say.

“It’s hard to ramp up when you don’t have the vaccine,” Findley said. “We have partners that we’ve been engaging with, getting them ready, prepared to receive vaccine, but if we don’t have the vaccine to give them, we pretty much can’t move very far.”

Anthony Fauci, the nation’s top infectious disease expert, predicted Tuesday that the country could soon be giving one million vaccinations a day. He said President-elect Joe Biden’s plan to vaccinate 100 million people in his first 100 days in office was “very realistic.”

On Friday, Biden proposed distributing to the states all the vaccine held by the federal government, which would include reserves intended for second doses. Levine said that plan would work as long as second doses will be available.

“We’re all on the same page of wanting to get these vaccines out as quickly as possible,” Gov. Tom Wolf said Friday.

Staff writers Erin McCarthy and Allison Steele contributed to this article.