When it comes to wearing masks in public, South Philadelphia resident Major Van Winkle believes "people are heading in the right direction."

"It's something we have to do," he said. "It's something we can do to help one another."

But not enough people are doing it, according to Dr. Thomas Farley, the city's health commissioner, and the reluctance to wear masks by many people is hurting Philadelphia's chances of reopening more businesses this week.

New daily COVID-19 cases in Philadelphia have again reached more than a 100 in recent days, up from totals that reached the 70s and 80s earlier in June, Farley said. Pennsylvania, on a whole, has seen an increase in cases in recent days, according to state data.

A study conducted by the Health Department last week found that 78% of people inside retail stores wore masks and 55% wore masks on public transit.

"I'm very worried that hospitals there are going to become overwhelmed and any steps we take here are with that in mind," Farley said in an interview Monday. "We don’t want to become another Houston or another Miami."

He said earlier Monday that the city may not be able to move to the green phase of Pennsylvania's reopening on Friday as planned. That would mean restaurants, bars and other businesses that would like to start operating at limited capacity indoors may have to wait longer to do so. New Jersey Gov. Phil Murphy said Monday that plans to allow some indoor dining would be shelved for now.

"We’re not seeing the decreases," Farley said. "We’re plateauing and we’re not getting below 80."

That's a number the city would like to see daily before it moves to a more widespread reopening of indoor activities.

A lot of the new cases involve younger patients than the early months of the coronavirus pandemic.

"Well if there’s anything we can recognize, it's that more people are involved in social gatherings," Farley said. "We’ve seen increases in people who are teenagers and in their young adult years."

Neither state officials nor Farley said Monday that there is any current plan to shut down businesses that have already reopened in the last month. Farley also would not say Monday if Philadelphia has postponed plans to move to green later this week.

But he would confirm that further reopenings are expected either. Farley and Mayor Jim Kenney are expected to announce more details to the city's phased reopening at their biweekly press conference Tuesday afternoon.

Pennsylvania Health Secretary Dr. Rachel Levine said that excitement over reopenings of some businesses should not stop the public from wearing masks or forget the social distancing and hygiene practices recommended since the outbreak began.

"it’s been great to go green," Levine said Monday. "We still have to be careful. We have to stay vigilant. We have to stay alert. COVID-19 is still in our communities."