Banner Health, Arizona's largest health system, on Monday launched drive-thru COVID-19 testing for prescreened patients at four sites, three in Phoenix and one in Tucson.

Patients do not need a doctor's order, but they will need to speak by phone with a Banner clinician before being scheduled for a testing appointment.

That's why Phoenix-based nonprofit Banner Health isn't publicly sharing the addresses of the sites: Patients need to call ahead. People who arrive at a testing site without an appointment won't be tested, officials said.

The addition of the Banner sites is expected to broaden testing in Arizona. Many Arizonans have complained about having COVID-19 symptoms but say they've been unable to get a test. The availability of testing has been an obstacle for some clinicians, too.

Arizona as of Monday had 234 reported presumptive positive and confirmed cases of the disease, which is caused by the new coronavirus. The state also has had two known COVID-19-related deaths.

But the number of cases in Arizona could be much higher than the reported tally because of limited testing. Arizona's first case of COVID-19 was confirmed Jan. 26. Arizona's state lab became one of the first in the country to begin doing its own testing on March 2.

Other entities are providing testing services as well.

In early March, Phoenix-based Sonora Quest Laboratories began doing testing in Arizona, as did North Carolina-based LabCorp.

The Mayo Clinic in Arizona last week began doing testing for Mayo patients with a doctor's order at both its Phoenix and Scottsdale campuses. Coconino County in northern Arizona is operating two testing sites in conjunction with the Phoenix-bases Translational Genomics Research Institute.

Though testing is not a panacea to the COVID-19 pandemic, it can give public health officials a better idea of where hot spots are located and how to best respond, and it can give individuals incentive to self-isolate and practice social distancing.

CORONAVIRUS TESTING:COVID-19 testing is ramping up in Arizona. Here's what we know

No symptoms = No test

The Banner testing began with a "soft launch" in Tucson last week, but the testing sites officially opened Monday. The nasal swab tests will be processed by Sonora Quest Laboratories, with a turnaround time of three to five days to get results.

The general vicinity of the sites in Phoenix are the northwest Valley, the southeast Valley and one in Mesa. Several more are slated to open at a later date, Banner officials said. They could not give an estimate of how many people per day they will be able to test.

"It will depend on our supply of test kits," company spokeswoman Becky Armendariz wrote in a text message. "We've been working with state and federal agencies to secure kits, and they have been very helpful and supportive. We will ramp up and open additional sites as more kits are made available to us."

The phone number to call is 844-549-1851 to speak with a clinical team member to determine if testing is appropriate. The line will be staffed from 7 a.m. to 6 p.m. Monday through Thursday and 7 a.m. to 5 p.m. on Friday.

In its news release about the sites, Banner says that if people meet CDC testing criteria, they will be scheduled for an appointment at one of Banner’s new drive-thru sites.

Banner officials are not sharing the precise criteria patients will need to have before getting approved for a test. Armendariz said she could not provide more specifics, other than to say people who get tested must have symptoms.

The clinician will then evaluate other criteria that might indicate the "likelihood of having COVID-19," Armendariz wrote.

The latest CDC interim guidance on testing is somewhat open-ended, calling for clinicians to use their judgment to determine if a patient has signs and symptoms compatible with COVID-19 and whether the patient should be tested.

COVID-19 can manifest with a range of symptoms, but the hallmarks are a fever, cough and shortness of breath. In more serious cases, the disease causes pneumonia. About 80% of cases have mild or no symptoms, the latest evidence shows.

The CDC guidance does recommend prioritizing certain individuals — hospitalized patients with symptoms who don't have another respiratory illness, and "older adults" and others at risk for poor outcomes. The CDC does not define the age of an older adult.

The CDC also recommends prioritizing people, including health care workers, who within 14 days of symptom onset had close contact with a suspected or laboratory-confirmed COVID-19 patient, or who have a history of travel from an affected geographic area within 14 days of their symptom onset.

What happens during the COVID-19 test

During patients' drive-through appointment, they will be asked to remain inside their vehicle, Banner officials said, and they will receive paperwork to complete, including a confirmation stating they are experiencing symptoms of COVID-19.

Patients must agree that once they are tested, they will self-quarantine until Banner contacts them with their test results. A Banner team member will then swab inside their nose to collect a sample.

The whole process will take five to 20 minutes, Banner officials said.

"If test results are negative, the patient will be informed they can return to their normal daily routine if they are asymptomatic," the Banner news release says. "It is recommended that they remain at home if they are still sick. While they may have tested negative for COVID-19, it is possible they have another illness that could spread to others."

Banner Health will notify the county and state health departments if a test is positive and provide the patient with the next steps, which could include an additional period of isolation. Abiding by the isolation period is extremely important to ensure the patient does not spread the virus to others, Banner officials said.

Banner officials said they want to stress two key points about the testing to Arizonans:

A Banner health care provider will determine if someone needs to be tested. This will be done through a phone screening. Individuals cannot request the test and will only be tested if they meet testing criteria.

Banner’s drive-thru sites will not accept unscheduled patients. Everyone must be phone screened in advance and scheduled for an appointment. Those who arrive without an appointment will be asked to leave and call 1-844-549-1851 to complete the phone screening process.

Arizona Gov. Doug Ducey on March 11 issued an executive order eliminating all co-pays, co-insurance and deductibles for new coronavirus testing. Banner Health said anyone without insurance will not be turned away from getting a test.

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

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