NEW HAVEN, Conn. (WTNH) — Yale Medicine Dr. F. Perry Wilson said the U.S. Centers for Disease Control and Prevention’s guidance to wear masks indoors in communities is based upon burdens on the health care system, not COVID-19 cases.

“That’s when they really turn up the restrictions, when they feel like the hospitals are getting too full, and after Thanksgiving, we have seen those numbers go ticking up,” Wilson said.

He said that hospitalizations have exceeded the threshold that triggers mask recommendations in some U.S. cities.

In New York, a health advisory notice was sent out alerting hospitals, local health departments, emergency rooms and labs to prepare for rapidly rising cases of respiratory illness. It’s now recommended to wear a mask in indoor settings, and crowded outdoor settings.

“This is not a bad idea,” Wilson said. “There is not only COVID out there right now, as most viewers will know. There’s a lot of upper respiratory infections and masks are fairly effective for most of them.”

Wilson said the “tripledemic” of the flu, COVID-19 and respiratory syncytial virus, better known as RSV, is taking its toll.

He said that while hospitals are back to pre-pandemic procedures, valuable hospital space for the sickest is being used up.

“There is quite a bit of strain on the hospital system right now, but I don’t think we’ll see that break until certainly well into the new year,” Wilson said.

When it comes to Connecticut, there’s resistance to the idea of a mask mandate.

“It’s been a long, arduous journey,” said Michael Levine, of West Hartford. “A lot of masks, you know, staying away from people, and that is tiresome, as well. I already had a really bad cold, so I should probably be more careful.”

Monday in West Hartford, some shoppers could be seen wearing masks while running errands.

“It’s not just about you,” Shereen Tewfik said. “It’s about other people, and protecting not just your family and loved ones, but it may be a stranger that is immunocompromised.”

Dr. Sharon Stoll with Yale Medicine said that with flu and RSV season in full swing, hospital occupancy is “worse than it ever was.”

“Hospitals are full now then they were in previous years,” Stoll said.

Like with COVID-19, patients are the most contagious before their flu symptoms set in, which means that masking can help stop transmission.

“And that is the time when sometimes people are most contagious, similar to COVID, where you don’t know if they’re contagious or not, and that’s where something like the N-95 may be more beneficial,” Stoll said.