As registered nurse Bridget Sullivan walks up and down the rows of patient pods at Boston Hope, the rhythmic noise she makes is unmistakable.

"You can hear my gown swishing, and all my PPE," she says.

Her personal protective equipment is a gown or white full-body suit, N95 mask, gloves and face shield. And even though it can be uncomfortable, Sullivan is grateful to have it.

She's wrapping up another 12-hour shift in the respite shelter for people who are homeless and have the coronavirus, located in the Boston Hope field hospital at the Boston Convention and Exhibition Center. There are 500 beds dedicated to people experiencing homelessness. So far, those beds have never been full. About 300 people who are homeless have stayed here since the field hospital opened almost four weeks ago.

The facility — which was conceived and constructed by city and state leaders, the private health care providers now running it, and Suffolk Construction — has allowed Boston to have a ready supply of beds for people who are homeless, as it's worked toward testing the entire adult homeless population for the coronavirus over the last few weeks (testing that is expected to be complete this week). The Federal Emergency Management Agency is expected to cover 75% of the costs tied to the facility, according to Mayor Marty Walsh's office.

As Sullivan records herself doing the final walk-through of her shift, she mentions the patients she sees at the small movie theater that's been set up. Staffers play cornhole with patients. There are puzzles, crafts and bingo. Patients use laptops at the "internet café" to play games or look for jobs or housing.

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Staffers from Boston Health Care for the Homeless Program, which is running the facility, have tried to make it feel less like a hospital and, cavernous as it is, more like a home, Sullivan says.

The coronavirus is one of many struggles their patients are facing.

Epidemic Within The Pandemic

"Now I'm going to make a couple laps around the unused units and make sure that nobody's crawled into a bed that maybe they shouldn't be in," Sullivan says. "We're very vigilant about harm reduction and the opioid epidemic, and we just want to make sure that nobody's gonna get harmed in our facility."

Sullivan and her colleagues point out the opioid epidemic is still in full force, in the midst of the coronavirus pandemic. Workers from the Boston Public Health Commission armed with the overdose reversal drug Naloxone are stationed outside the bathrooms. They're making sure no one is inside too long. So far there have been no overdoses.

Patients are able to get their methadone and Suboxone treatments at the facility. Those not in treatment are at risk of painful withdrawal, without a ready drug supply.

"People are not allowed to go out on the street ... So that can present a pretty significant challenge ... if they are active in their substance use disorders," Sullivan explains. "They are not locked here, however. They can sign out against medical advice if we're unable to manage their detox well enough."

So far two people have signed themselves out for that reason, 13 others because of different personal concerns, according to Sullivan.

'Uprooted' and 'Triggered'

The people staying here have either no COVID-19 symptoms or just mild ones. That's the case with the vast majority of people who are homeless in Boston and have had the coronavirus, according to doctors who've overseen the testing. But unlike the general population, these patients can't isolate at home.

"Our patients come from an extremely stressful environment to begin with, staying in a shelter with hundreds of other people ... dealing with the stresses of extreme poverty, violence," says Dr. Peter Smith, a physician with Boston Health Care for the Homeless who is co-directing the Boston Hope homeless respite with Sullivan. "And then to throw this terrifying illness on top of it — the fear that ... there is no way to isolate yourself or protect yourself from from illness, is really anxiety provoking for a lot of people."

The first 24 to 36 hours at the field hospital are critical, according to Sullivan.

"We're seeing people uprooted and sometimes triggered by previous traumas ... and checking in with them as quickly as we can on admission," she says. "[We're] setting up telehealth appointments with psychiatrists and making sure that they have their medications, and making sure that they feel supported and they know who to talk to."

Social workers provide group therapy on site. Clinicians help people manage their chronic medical conditions, including diabetes, heart disease and HIV.

Occasionally, someone's COVID-19 symptoms intensify.

"We have seen people who come in with very mild illness and then suddenly develop worsening shortness of breath and fevers," Smith says. "And so we do have to keep a close eye on that."

Smith and Sullivan say so far, half a dozen patients have been transferred to the neighboring exhibition hall at Boston Hope. That's the full field hospital run by Partners HealthCare.

'Boston Hope Gave Me That — Hope'

And as patients at the respite shelter recover, they're making clear what the care here means to them.

"Walking by our board of thanks, we have a bunch of patient messages in Spanish and in English," Sullivan says as she finishes her walk-through.

Patients express their gratitude in magic marker on a white board, along with in- person conversation and handwritten letters.

"Thank you to all the nurses and doctors. There is no amount of anything that can repay these workers here," Sullivan reads from  a message on the white board. "Boston Hope gave me that — hope."

Sullivan is struck by her patients' resilience. Many of them have faced years of isolation that she says have, sadly, prepared them for the crisis brought on by the coronavirus.

The staff cheers for some of the patients as they're released — the ones who are in the frame of mind to celebrate having beaten the coronavirus, even as they're not going back to their own homes; they're returning to homeless shelters.

Smith recalls one patient who was "bowled over" by Boston Hope.

"He was so happy that everybody had come together to provide this for our patients," Smith recounts. "But then he sort of stepped back and reflected and was like, you know, 'If we were able to do this all along, how come it never was done before? How come when there wasn't a health care crisis, people weren't weren't doing this for homeless people?' "

Those at the field hospital hope the spirit that led to this facility will carry on in the form of greater cooperation to help people struggling with homelessness after the crisis is over.