A parking lot in San Juan turned into a staging area Tuesday morning as about 10 doctors, nurses and administrators gathered between rows of parked cars glistening in the Puerto Rico heat.

Some showed up in scrubs, some in jeans. All were ready to work with patients.

Leading the charge was Dr. Carla Rossotti, a primary care doctor who has been leading medical teams into communities that have had little to no medical care since Hurricane Maria made landfall almost three weeks ago.

With only about 16 percent of the island back on power, and many communities receiving no cell service, channels are still limited with which to communicate medical needs.

Compounding the hurricane’s impact, recent rains left blackouts and some roads washed out, creating more challenges to a fragile recovery.

The group would be traveling to a shelter in Coamo, a community in the island’s interior, hard hit by the hurricane’s path that bisected the island, just 100 miles across.

The team piled into a pair of vehicles, along with emergency medicines from Direct Relief, and started on the two-hour drive to the shelter. On the way to the shelter, Rossotti got a call about a man needing dialysis medications.

The man depended on dialysis three times a week, but had only been able to get treatment once a week, and was suffering physical symptoms.

The signal bars on Rossotti’s phone began to drop off, just as she was able to refer the person to a contact that might be able to help.

Having connection issues during such an important call is the norm, but left the doctor rattled.

“It’s very stressful,” she said.

The recent rains have made the green vines begin to grow up around the brown, broken trees that stretch as far as the eye can see. It’s difficult to imagine the powerful winds that would have turned the Puerto Rico’s lush hillsides into denuded expanses.

Between the broken trees lining the roadways, stopped cars cluster on the shoulder of the highway periodically.

“There’s cell signal here,” Rossotti said.

Indeed, drivers sit in their car glued to their phones for the bit of connectivity that pops up sporadically, without any seeming pattern.

It’s a time when even getting a text message or a call on a cell phone seems like a small miracle.

Rossotti and her team have been to a dozen clinics in the time since Maria made landfall, and her team has been working nonstop to provide care in shelters.

Diseases and conditions that arise when people live in close quarters and have limited access to hygiene are becoming common: pinkeye, lice, scabies, gastrointestinal issues.

Mosquito-borne diseases that were a concern before, are heightened now with a profusion of standing water. Dengue, Zika and Chikungunya are a threat, Rossotti said.

Leptospirosis is also a concern, the doctor said. With many people lacking access to water, they’ve turned to drinking from streams, which can be contaminated. The water-borne bacteria can cause organ failure if not treated in time.

When the group pulled up to the shelter, which was housed in one of Coamo’s elementary schools, Rossotti and her team checked in with the shelter supervisor, who directed them to a room they could use to set up a mini-clinic to treat residents.

The school’s library would be the place for patients, and the group worked quickly to disinfect tables and assign workstations.

The library’s five tables would serve as an intake station for patients, a pharmacy and patient stations. A more secluded table would serve as a place for Dr. Shaila Hung, the psychologist who had traveled with the group, to see patients.

Many of the fifty-seven people living at the shelter had not had any medical care since the storm made landfall, and residents began lining up for care before the group had even finished set up.

A young mother named Yaomara was one of the patients to come through the door.

One of the nurses put a cuff around her arm to measure her blood pressure, and after speaking with the patient, Dr. Rossotti provided her medication to manage her blood pressure.

Yoamara, her husband and three children were all living at the shelter, and had been on the margins before the storm hit, with both she and her husband out of work.

When the hurricane hit, it took all they had. The roof of their home was ripped from its bearings, and all of her belongings were destroyed by the wind and the water.

Now, the family is waiting for a determination of whether the home is safe to return to. Her children can return to school in a few weeks, but by then, the family will have been living in the shelter for a month.

For the meantime, however, she had what she needed to manage her health.

Across the room, in the secluded corner, an older woman dabbed her eyes as she talked to Dr. Hung. The psychologist listened intently as the woman shared that her home had been destroyed in the storm, and how difficult the weeks following had been.

Hung has heard similar stories at the other shelters the group has visited, and said that everyone is processing the trauma left by Maria.

After a crisis, people are often more concerned with their homes, families and even other areas of health before they tend to mental health.

“The priorities become other things,” she said.

For a few hours, however, patients living in the shelter had their health be the priority of a small team of doctors, equipped with the right tools.