TUBA CITY — Tuba City native Dr. Sophina Calderon comes to work every day with a sense of dread about whose face or name she'll recognize among the COVID-19 patients of all ages hospitalized here.

While nationwide people older than 60 have been hardest-hit by COVID-19, in Tuba City, Calderon has seen younger people, particularly those affected by diabetes, seriously affected, she said. And among every 20 or so patients who come into the hospital, whether it's to be triaged, tested or admitted, she'll see a familiar face or name.

The virus also is unpredictable, Tuba City health officials say. They cite instances where multiple family members are living in the same household, yet only one or two get sick with the virus.

They point to three factors that have fueled the spread of COVID-19 on the vast, rural Navajo Nation: A large event in the community; the fact that Native Americans as a group have a higher rate of underlying health conditions, including diabetes; and the fact that families often have members of multiple generations all living under the same roof.

Not long after a March 7 religious rally in the nearby Navajo community of Chilchinbeto, patients with low oxygen saturation rates, fever and trouble breathing began seeking care at the hospital in Tuba City.

There has been no sign of a slowdown since.

As of Tuesday, the Navajo Nation, which has reservation land in Arizona, Utah and New Mexico and about 180,000 residents, reported 838 positive cases and 33 known deaths. Most of the positive cases — 543 — were in Arizona, the tribe reported.

At least half or more of the COVID-19 deaths on the reservation to date have been people from the Tuba City area, said Lynette Bonar, CEO of Tuba City Regional Health Care. Health care workers have been affected, too.

"I think it's going to be difficult for the Navajo Nation to move forward because when people do get it, it's hard to tell who will be affected the most by it," Bonar said.

Medical officials on the Navajo reservation in Shiprock, New Mexico have started referring to suspected COVID-19 cases as "families under investigation" rather than "patients under investigation," she said.

"I think living together and not being able to isolate or quarantine yourself is difficult," Bonar said. "This virus is very hard on people, even healthy people. It's very hard on people over 40. But we see people in their 30s not doing well, either."

Sweat lodges and COVID-19

State health officials call what's happening on the Navajo Nation a "significant outbreak" that has made headlines across the country as a hotspot for infections. The reservation was also hit hard during the H1N1 flu pandemic.

The Arizona Department of Heath Services, which began releasing breakdowns of COVID-19 deaths by ethnicity on Sunday, reported Native Americans as of Wednesday comprised 21% of COVID-19 deaths where race and ethnicity was known. American Community Survey's 5-year estimates show about 4.6% of Arizonans are American Indian or Alaska Native.

The Tuba City hospital is not releasing demographic information about patients on its public COVID-19 dashboard, though it is reporting data to county and state health officials.

Calderon, a family physician, was born at Tuba City Regional Medical Center, grew up in the area, was a teacher in Tuba City before going to medical school on the East Coast and now lives with her own family in staff housing on the medical campus. Some of the health care employees are related to one another and the Tuba City area is a tight-knit community.

Calderon has become a COVID-19 educator for the community, going on radio programs on both the Navajo Nation and Tuba City radio stations. She's also appeared on a Facebook Live forum to answer questions. The hospital itself has become a symbol to the community of how serious the disease needs to be taken, she said, with workers wearing masks screening anyone who comes into the campus, and a pharmacy that has switched to drive-up and is operating 24/7.

She's been able to see the spread of the disease unfold in her community close-up.

"We're starting to see higher numbers of younger people having bad, bad presentations of COVID-19 here in Tuba City, I think because they have some of these comorbid conditions," Calderon said. "A lot of the older people I see, the 70 to 80 year olds, are actually quite healthy...Most of them have continued to do traditional things like work with their sheep and be very physically active and I think that's helped them a lot be quite strong at baseline."

A comorbid conditions refers to an underlying health condition that could worsen COVID-19, the disease caused by the new coronavirus. Comorbitiies may include diabetes, heart problems and preexisting respiratory problems like asthma. Among Navajo Nation members, onset of serious Type II diabetes often happens when people are in their 30s, she said.

While some experts have pointed to a lack of running water as a significant risk factor for COVID-19 on the reservation, Calderon said factors like the rate of diabetes, and the tight-knit nature of the community, where families attend gatherings as a group, are the more prevalent risk factors she's found.

Calderon herself grew up without running water or electricity and her parents live in that same home. Her family delivers food to them now that they are sheltering at home, she said.

There was some talk in the Tuba City community about killing the virus through sweat lodges. Calderon did her best to get the message out that spiritual healing is a good supplement for many people, but that sweat lodges should only be done with immediate family members. Also, there's no proof that they will be effective in killing he virus.

"Within your own household it's OK to do a sweat lodge, but not if you are inviting other families," she said.

Symptoms are sometimes anxiety

Calderon has had to relay the painful message that no visitors are allowed at the hospital.

"When someone falls sick we sort of are restricting any contact between the grandchildren and their grandparents, and that's just something that really goes against how close people prefer to stay," she said. "That's been really hard...We've even heard feedback that sticking together is more important. It significantly impacts the family because they are very, very close."

Both the community and health care workers are fearful about the COVID-19. In triage, symptoms of COVID-19 are sometimes due to anxiety, and not the virus, said Bonar, a registered nurse and tribal member who lives across the street from the medical center.

There were 19 patients hospitalized in the Tuba City hospital for COVID-19 on Wednesday.

Nearly every day Tuba City is sending patients for care at Flagstaff Medical Center or to hospitals in Phoenix that are staffed with pulmonologists and intensivists who specialize in critical care. Sometimes the patients need ventilators to help them breathe. Many of the patients in the past week have come from the Indian Health Service's Kayenta Health Center near Chilchinbeto.

"I know Flagstaff Medical Center is getting close to full," she said. "They get to the point where they need to save room for people in the community. We had one day where we had nine transports out and every other one we sent to Phoenix."

Since the outbreak began, the Tuba City hospital has sent at least 40 COVID-19 patients who needed ventilators to other hospitals, Bonar said. The hospital has seven ventilators, which includes one for travel.

The Tuba City hospital plans on using an existing building on its campus to create a transition "step-down" unit with eight to 10 beds where patients may stay and recuperate away from their families, and already has a commitment from the Phoenix-based global medical relief organization Project CURE to provide needed equipment for that transitional area.

In addition, the Federal Emergency Management Agency is constructing a medical station in Chinle two hours east of Tuba City where Bonar expects Tuba City patients will be able to recover if needed.

Looking at the contact tracing of infected tribal members that has occurred, Bonar believes the outbreak most likely began at the church rally, which drew tribal members from all over the vast reservation. Those people went home to their communities and the disease spread.

The Navajo Nation area as of Wednesday had the most positive COVID-19 cases of any other area in the U.S. Indian health system, federal officials wrote in an emailed statement to The Arizona Republic.

Like other parts of Arizona, testing as been a problem at the Tuba City hospital, which has prioritized testing for only the sickest people as well as health care workers and first responders with symptoms, because of a low number of test kits. Since March 12, there have been 160 positive tests, which is nearly half of the 338 COVID-19 tests that Tuba City Regional Health Care has administered at three sites.

The three sites where the testing is conducted are the main Tuba City campus, a clinic in LeChee, which is on the Navajo reservation near Page, and at Sacred Peaks Health Center, which serves Native Americans in Flagstaff.

The Indian Health Service is working closely with the data experts from the U.S. Centers for Disease Control and Prevention to address concerns regarding "accurate surveillance and reporting of COVID-19 among American Indians and Alaska Natives," the statement says.

IHS is also working closely with the CDC data team to address concerns regarding accurate surveillance and reporting of COVID-19 among American Indians and Alaska Natives.

10 nurses home with COVID-19 symptoms

Tuba City Regional Health Care's six-bed ICU now cares solely for Covid-19 patients and its pediatric clinic has been converted into a respiratory care unit reserved for patients who are suspected to have or have tested positive for the disease.

The hospital has 73 beds but less than half — 35 — are in operation now due to staffing. Typically the hospital has the staffing to operate 50 beds.

At least 65 of the health care center's 1,100 employees have at some point since the crisis began been at home and unable to go into work due to COVID-19 symptoms, including some who tested positive, Bonar said.

"We're dealing with the after-effects of some staff having contracted the virus," Bonar said. "We've probably been at about 65 to 100 people at home with symptoms since this has started, I would say, rolling until now. I know that we have 10 nurses out."

She said officials believe they contracted the virus through community spread, not at the work setting.

The hospital is in need of ER and ICU nurses, and will hire on a per diem basis, Bonar said.

The nursing shortage predates the COVID-19 pandemic and increasing those staffing levels is part of a long-term goal. In the meantime, the Tuba City hospital cares for as many COVID-19 patients as it can.

Anyone who visits the health campus in this city of 9,000 is immediately screened by employees of the health center, who stand in a roadway leading to the entrance wearing fluorescent traffic vests, and holding clipboards with colored stickers — green means proceed, red means go to a triage tent at the back of the campus for further examination.

Patients who need further care after triage are sent into a "red" ER, which has its own entrance. Those without respiratory symptoms are directed to a "green" ER.

The Tuba City Chapter House put up the tent so that the hospital would not have to risk having symptomatic people walking through an indoor waiting room. There have been rumors that The National Guard put up a tent with hospital beds here. That's not true, though the National Guard has been deployed in other parts of the reservation to help with the pandemic.

Sitting on a chair in the roadway near the screeners is a bin of cloth masks. They hand one out to anyone who doesn't have one. In accordance with new guidance from both the Arizona Department of Health Services and the U.S. Centers for Disease Control and Prevention, the hospital is asking all visitors to wear masks as a protective measure.

Evidence is showing that people without symptoms can still spread the virus, which is a message that Calderon is trying to get out to the community. On Tuesday, there were signs the message was resonating. A car with two people from the Tuba City community who otherwise had no reason to visit the campus drove up to the screeners and asked if they had any masks to spare. They each got a mask and left.

"The CDC and other places don't really know how long this virus is staying in the air," Bonar said. "Our communities are fearful, as well as our staff. We don't know how bad this is going to affect people."

She praised the Navajo Nation for imposing curfews and is hopeful that in a week or two, the spread will begin to slow. The hospital remains prepared for a surge, but Bonar remains hopeful that it won't happen. She likes to remind her staff that most people who are infected with COVID-19 have a positive outcome.

As an example, the Tuba City hospital since last month has discharged 42 COVID-19 patients who are at home and recovering, according to the hospital's COVID-19 dashboard.

"Even with our employees here who have tested positive, there have been a few of them come back (to work) and they are just fine," Bonar said. "I try to tell our staff that they are going to see the worst come into our hospital but it's not a picture of everybody who gets it. It's scary for everybody because when you work at a hospital you see the worst. This is a smaller percentage of the whole."

Republic reporter Rachel Leingang contributed to this article.

Reach health care reporter Stephanie Innes at Stephanie.Innes@gannett.com or at 602-444-8369. Follow her on Twitter @stephanieinnes

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