As a slew of Northeastern states announced plans this week to end mask mandates, Philadelphia was among major cities that did not change their plans.

Philadelphia’s COVID-19 hospitalizations and death counts, poverty levels, and residents’ underlying health conditions contributed to the city’s decision to keep its indoor mask mandate for businesses and public spaces in place, as neighbors like New Jersey and Delaware moved to ease school masking requirements.

“Hundreds are getting sick every day and hundreds more in the hospital — you’re still in the middle of a pandemic,” said James Garrow, a spokesperson for the Philadelphia Department of Public Health. “We understand that people are frustrated and we know that things are getting better, but we’re still not at the point where we think things are safe.”

In 10 states, including New York, Massachusetts, and California, announcements this week about plans to lift indoor or school mask mandates reflected governors’ optimism about the omicron surge’s decline and likely political concerns about a public increasingly exhausted by public health measures.

Those states’ masking policy changes will go into effect in coming weeks. Still, some experts have cautioned against unmasking prematurely.

Though “we’re getting there,” said Jennifer Kolker, associate dean for public health practice at Drexel University, states may be relaxing restrictions too soon.

“It feels a little bit overeager,” she said.

Pennsylvania does not have a statewide indoor mask mandate, and its requirement for masking in schools was struck down by the state Supreme Court in December.

City officials have said Philadelphia’s mandate will likely continue for several more months. In the coming weeks, however, the city plans to release benchmarks that, when reached, would signal a reprieve from mask mandates and, eventually, vaccine mandates for indoor dining.

City health officials likely won’t announce a specific date for the end of mandates. They’ll use case counts, test positivity rates, and hospitalizations to decide whether mandates are needed, Garrow said. Vaccination rates are also critical, Kolker said.

» READ MORE: Lifting COVID-19 mandates likely still ‘several months away’ in Philadelphia as omicron recedes

“We worry about places dropping mask mandates tied to a date,” Garrow said. “There’s nothing to stop the disease having a new variant sweeping the country three days before.”

Relaxing COVID-19 safety mandates, though, Kolker said, doesn’t necessarily mean they’ll be gone for good. New variants and seasonal surges may mean safety restrictions will adjust depending on how COVID-19 is moving in the region. Setting clear benchmarks for when restrictions are mandated, or just recommended, would make shifts feel less arbitrary, she said.

Garrow acknowledged fatigue with pandemic mandates but said the health department has to balance the comfort of people at less risk from COVID-19 against the safety of people still at significant risk from the virus. The immunocompromised, for example, can get seriously ill even after receiving vaccines and booster shots, and restrictions like the city’s indoor dining vaccine mandate may give them confidence to resume activities they would otherwise consider too risky.

The city’s high poverty rate — about a quarter of the population lives at or below the poverty line — is another factor, Garrow said.

“Philadelphia is the poorest big city in the country, and with that poverty rate comes people with more serious conditions,” Garrow said. “More people are sicker here,” making them more vulnerable to COVID-19.

A city’s health considerations also include greater density, Kolker said, more reliance on public transportation, and more indoor gatherings.

Philadelphia is not the only big city standing firm on indoor mask mandates. Boston and Los Angeles are keeping their mandates even as their states relax masking policies. Chicago, however, will likely allow its mandate to lapse when Illinois’ does at the end of the month.

» READ MORE: New Jersey is ending its mask mandate for students, leaving the decision up to school districts

New York City didn’t have its own indoor mask mandate, and relied on the recently ended statewide mandate. That city’s masking policy is now less restrictive than Philadelphia, but masks are still required in settings like public transportation, health-care facilities, and group residential facilities. The city’s indoor dining vaccine mandate is also still in effect.

“For the most part, states don’t preempt cities for doing what’s right for its cities,” Kolker said, adding, “We have good reason to be more cautious than other parts of the state.”

Despite pandemic fatigue, an estimated 79% of people are putting masks on inside Philadelphia businesses, according to the city’s review of surveillance video of people coming in and out of shops. An increase in mask wearing roughly coincided with the omicron variant surge.

The city’s vaccination rate continues to grow, with about 74% of people 12 and older fully vaccinated, and about half of children receiving at least one dose, according to city data.

In Philadelphia on Thursday, an average of almost 4% of tests were positive over the last two weeks, and the city’s death rate was slightly above the peak reached at the beginning of 2021. Hospitalizations in the city are now a third of where they were at the peak of the omicron surge.

All states are under a masking recommendation from the CDC, which has not yet recommended that Americans should go maskless in public indoor areas. Masks remain federally required in high-risk health-care settings and on public transportation nationwide, including on school buses. The CDC is working on post-surge guidance but isn’t ready to recommend dropping masks, its director told the New York Times this week.

In part, the lack of clear benchmarks is because new variants like delta and omicron can rewrite the script for what is safe as the pandemic continues.

“Everyone’s trying to figure out what to do without getting clear guidance,” Kolker said. “We need metrics now for the next chunk of time, and I think we’re always going to go back and modify those metrics.”

These states announced changes to their indoor masking policies this week:

California

California’s mask requirement for indoor public spaces and workplaces will end Feb. 15. But some counties, including Los Angeles, will keep a mandate in place.

Connecticut

The school mask mandate will expire on Feb. 28.

Delaware

Delaware’s universal indoor mask mandate expires Friday. Its mandate for schools will continue until March 31. Gov. John Carney urged parents to vaccinate their children before that date.

Illinois

The statewide indoor mask mandate will be lifted by Feb. 28, but the requirement for schools will stay in place.

Massachusetts

The school mask mandate will be lifted on Feb. 28.

Nevada

The state dropped its indoor mask mandate for public places and schools on Thursday, effective immediately.

New Jersey

The state’s mask mandate for schools and child-care settings will be lifted March 7. Gov. Phil Murphy cited the improvement in the omicron surge, including declining case and hospitalization numbers. Health officials said they believe waiting until March will ensure the transmission rate has dropped low enough and give school districts, teachers, and parents time to prepare.

New York

The indoor business mask-or-vaccine mandate, which was implemented as the omicron variant took off, was lifted Thursday. Gov. Kathy Hochul said this week she will reevaluate the school mask mandate in early March.

Oregon

The state health department plans to lift the indoor mask mandate no later than March 31, and end the school masking requirement on March 31.

Rhode Island

The state’s school mask requirement will be lifted March 4, and the universal masking order for businesses and venues will expire March 11.