Nestled in blue cold storage containers and between cold packs preserving a stable temperature from the humid San Juan air, precious vials of insulin were transported across the city Wednesday.

As the transport unfolded, winds whipped up palm trees still ragged from Hurricane Maria’s winds three weeks ago, and a rainstorm earlier in the day brought sheets of water so constant that it was difficult to see.

The daily rains have left portions of the city in a blackout cycle. As fledgling power comes back, another set of brutal rains appears to snuff it out.

Insulin must be kept cool, a challenge when power throughout the island is scarce. But many clinics and hospitals are running on generator power and have the ability to consistently refrigerate crucial items, like insulin and vaccines.

The need for insulin was higher than ever at a San Juan health center called Health ProMed, where much of Wednesday’s Eli Lilly-donated shipment was bound.

The clinic sits in the Barrio Obrero neighborhood of San Juan, home to a significant population that has immigrated from elsewhere in the Caribbean, primarily from the Dominican Republic.

The center serves about 15,000 patients a year, almost all of which are living in poverty, according to data from the Health Resources and Services Administration.

Sixteen percent of ProMed’s patients have been diagnosed with diabetes.

The center has two clinics in San Juan, as well as locations on the Puerto Rican islands of Vieques and Culebra. All of the clinic’s communities have been seriously impacted by Hurricane Maria, with many patients struggling to survive post-storm.

On hand to help move the insulin into cold storage was Angel Rodriguez, who works as the clinic’s director of nursing.

He and other staff members quickly moved the boxes of insulin into the clinic’s refrigerators, carefully taking inventory of the medications.

“Our patients don’t have enough cash to buy what they need,” he said, adding that if people do have money for food, cheap fillers like cake and candy are often all they’re able to afford.

The storm’s impacts have wiped many out financially, leaving them with even fewer options.

Stress is also a trigger for blood sugar to skyrocket, he said, and that “the anxiety of living brings those levels high.”

With many too ill to leave their homes for care, the center has a small brigade of outreach workers who leave the walls of the clinic to bring medicine and care into the community.

“We are in the streets identifying patients,” he said.

That care becomes very personal very quickly, with each worker bringing the exact dosage and medication a patient will need for the next few days. A fragile connection to health from the outside world.

Rodriguez pulled a package out of cold storage, a bundle about the size of a sandwich, wrapped in white paper, with a patient’s name written on the side.

Inside, precious insulin that a health worker would take to a patient trying to navigate post-storm life.

They won’t do it alone, because “we bring it to them now,” Rodriguez said.