The coronavirus variant first identified in the United Kingdom is likely spreading across the Philadelphia region at a higher rate than is being detected, with new cases confirmed Wednesday in Montgomery County and at the University of Pennsylvania.

Four people who caught the more transmissible strain have spread the virus to others in Montgomery County, officials said. None of the four reported having recently traveled.

“All of this signals to us that the variant is likely much more widespread within the community than can be confirmed through lab testing,” said Dr. Val Arkoosh, a physician and chair of the Montgomery County commissioners.

Experts agree the U.K. variant is transmitted more easily between people than the original COVID-19 strain, but say it has not mutated enough to render the existing vaccines ineffective. They’re still studying whether it is more deadly, according to the CDC.

The strain has also been found in Philadelphia and Bucks County. As it and other mutations of the virus spread across the world — variants that were first detected in South Africa and Brazil are also being monitored — the Biden administration was reportedly considering Wednesday whether to impose domestic travel restrictions aimed at stemming the spread.

Centers for Disease Control and Prevention Director Rochelle Walensky warned at a White House briefing this week that although coronavirus cases and hospitalizations are dropping after the winter surge, Americans should keep up their guard.

”The continued proliferation of variants remains of great concern, and is a threat that could reverse the recent positive trends we are seeing,” she said.

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Those positive trends have continued in Pennsylvania and New Jersey, and the Garden State even planned to look at lifting more restrictions. As the limited number of doses strains the vaccine rollout, Montgomery and Allegheny Counties, which were among the Pennsylvania counties that received many fewer doses than usual last week, are set to receive more shots this week.

Hard to trace

In Philadelphia, seven cases of the variant have been identified but officials “expect that the true number is higher,” said Health Department spokesperson James Garrow.

Two students at University of Pennsylvania, which resumed on-campus instruction this semester, were infected with the variant in the past month. Their cases were linked to travel from the United Kingdom, the Daily Pennsylvanian reported Wednesday.

But the U.K. strain is difficult to detect, according to Penn Medicine, because it requires genetic sequencing testing, a laborious process. Because the university can’t do genetic sequencing for every campus case, it is impossible to say how many more cases there could have been on Penn’s campus, Erika Gross, chief operating officer for wellness services, told the student newspaper.

A university spokesperson told The Inquirer on Wednesday the school was analyzing case data that could lead to more restrictions on campus “as an initial response to this most recent worrisome trend.” Last week, the positivity rate among undergraduate students was 4.47%, according to the school’s dashboard.

Through midweek, Philadelphia had administered 129,121 first doses and 54,858 second doses of the vaccine. The city reported 365 newly confirmed cases and 14 deaths on Wednesday.

In Pennsylvania, 767,164 people have been partially vaccinated and 317,338 have been fully vaccinated. The state reported 3,378 new cases and 125 deaths.

In Montco, a hotline and software fix

To address problems with the state-provided vaccine registration software, Montgomery County is finalizing a fix that will send out individualized, single-use links for people to schedule their inoculations, officials said.

The software, PrepMod, only provides universal links, which are being shared widely and causing registration problems in multiple counties, including overbooked clinics and ineligible people taking appointment slots.

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Arkoosh said she hoped the new feature would be ready next week. The county will continue to use PrepMod, which was provided by the Pennsylvania Department of Health and which officials across Southeastern Pennsylvania have complained has serious flaws, though Arkoosh said the county is looking to replace the system.

Montgomery County also launched a hotline for COVID-19 and vaccine questions. The hotline cannot be used to schedule appointments, although officials hope it eventually will. The number is 833-875-3967. Live operators will be available from Monday through Saturday from 8 a.m. to 8 p.m.

Last week, Montgomery County received just 1,000 shots intended for residents awaiting their first dose, far fewer than expected. The county went through that supply in two days, Arkoosh said, and had to close its mass vaccination clinic at Norristown High School until at least next week. The county expects to receive 3,900 first doses Thursday, along with its requested second doses.

Hospitalizations lower in N.J.

With 88 newly reported deaths, New Jersey surpassed 20,000 since the pandemic started, a number that “takes your breath away,” Gov. Phil Murphy said Wednesday.

Murphy was quarantining at home after one of his family members tested positive for the coronavirus. He and his wife both tested negative Wednesday and did not qualify “as an exposed close contact,” his spokesperson said, but Murphy decided to cancel in-person events out of an abundance of caution.

This is the second time the governor, who is 63, has quarantined after possible exposure, but he said he did not plan to get the vaccine until his age group became eligible.

New Jersey recorded 3,740 new virus cases.

The state has now administered 900,000 first doses, and more than 275,000 people are now fully vaccinated. About 100 CVS and Rite Aid pharmacies will start administering vaccines as soon as next week, Murphy said.

The state is also expected to receive more doses of vaccine over the next few weeks, health officials said, about 155,000 per week. Pharmacies will receive additional doses.

Hospitalizations are at their lowest levels in many weeks, Murphy said.

”If those numbers continue to go in the right direction, we’ll be able to clearly open things up further,” he said. But, he added, “I can’t tell you when or how much.”

Staff writer Laura McCrystal contributed to this article.