Pitkin County has maintained a high COVID-19 community-testing capacity since Curative tests were discontinued last month, but the number of people trying to find out if they have the virus has come down from an early-January peak.

In a few weeks at the beginning of winter, the county went from having a low testing rate to boasting one of the highest in the state, thanks in part to the widespread use of free tests available without a doctor’s order, deployed through a partnership involving the state of Colorado, local officials and the San Dimas, Calif.-based company that made and processed the PCR tests.

The number of tests given in Pitkin County more than tripled — from an average of 34 tests per day on Nov. 1 to 111 tests per day on Dec. 1, as the Colorado Department of Public Health and Environment (CDPHE) expanded the allocation of Curative tests beyond underserved populations and Aspen Valley Hospital set up two community-access sites (Aspen City Hall and in Basalt) offering the tests. After Dec. 1, the number of tests administered kept increasing, up to an average of 423 per day from Jan. 7 through Jan. 13.

The average daily number of tests performed during the month of January was 10 times higher than in October, according to CDPHE data.

Cumulatively, as of Feb. 1, Pitkin County had the highest testing rate among the three counties that make up the Roaring Fork Valley and the 10th-highest cumulative testing rate in Colorado, according to CDPHE data. On Feb. 1, Pitkin County’s cumulative testing rate per 100,000 was two times higher than Eagle County and 1.6 times higher than Garfield County.

Local testing capacity increased multifold due to proprietary labs and testing services that popped up in the valley, including Curative and multiple sites using Microgen tests administered by the Basalt-based private practice Roaring Fork Neurology.

Daily COVID-19 tests in Pitkin County. Credit: Graph by Laurine Lassalle/Aspen Journalism

But on Jan. 21, the state announced that Curative tests could not be used for asymptomatic testing after the Food and Drug Administration warned against false-negative results. The tests are more susceptible to false negatives, particularly in asymptomatic cases, in part because they are self-administered, requiring the user to collect a saliva sample and to place and seal it correctly in a solution.

“Out of an abundance of caution, we are stepping away from the use of Curative tests for both symptomatic and asymptomatic testing, to be effective at the end” of Jan. 22, said a Pitkin County news release dated Jan. 21. As of Dec. 30, the two community sites using Curative were testing about 840 people per week on average. Aspen School District also was using Curative for its campus testing program.

Despite the short notice, local public health officials were able to enlist Roaring Fork Neurology to continue administering free community COVID-19 testing at Aspen City Hall. At the time, Roaring Fork Neurology was already operating six sites throughout the valley, including a Basalt site, a drive-up kiosk at the Aspen airport and a site at Snowmass Village Town Hall.

Roaring Fork Neurology and its vendor can process up to 2,000 tests daily through its network of local testing sites, according to Dr. Brooke Allen of Roaring Fork Neurology. Results from the tests, which are processed at a lab in Texas, can be expected within 48-72 hours.

“The city of Aspen and Pitkin County Public Health have asked our team to take over the downtown Aspen kiosk starting Monday with our tests (which are MicrogenDx saliva PCR),” Allen said in a Jan. 21 email. “We will be resuming the same hours and location. We have the capacity to do many more tests than we are doing, and I don’t think Curative being discontinued will put us at capacity.”

Allen’s analysis proved correct and the shift from Curative to Microgen has not resulted in a testing shortage, local public health officials said.

“Testing has not decreased in PitCo,” Carly Senst, the COVID-19 testing and vaccination analyst for Pitkin County Public Health, said in a Feb. 1 email. “Microgen can and has absorbed all of the Curative capacity.”

After Curative was discontinued, an average of about 200 tests have been given daily in Pitkin County, according to CDPHE data.

STORY 3 Credit: Dan Bayer/Aspen Journalism

Rising wave crests

That level of testing represents a downward trajectory from a peak that began building in the runup to the holidays and reached its crest around Jan. 7. A similar curve follows daily new COVID-19 positive cases, which also peaked in early January and remain in decline in Pitkin County.

Senst said in an email that there’s “no single thing that is lowering how many tests we are performing, but a confluence of many.”

She added, “I believe that with fewer visitors seeking testing and community members potentially not being as exposed to all illnesses due to the red-level restrictions, we have fewer individuals feeling sick and thus seeking testing.”

Pitkin County on Dec. 14 began requiring overnight visitors to affirm they had a negative COVID-19 test in the 72 hours prior to arrival; lacking such a result, visitors were required to quarantine either for 14 days upon arriving in the county or until they received a negative COVID-19 test.

But as December progressed, the county’s incidence rate rose to become one of the highest in the state, peaking at more than 3,000 cases over 14 days per 100,000 people on Jan. 8. The local board of health placed the county under red-level restrictions effective Jan. 17, which closed indoor dining and limited any gatherings outside of the household. As the 14-day incidence rate declined from over 2,700 to under 700 per 100,000 people within two weeks, county officials lifted the ban on indoor dining effective Feb. 2, moving to orange-level restrictions. Yellow-level restrictions, which allow indoor dining at 50% capacity, may take effect Saturday, pending new case numbers released Friday.

Josh Vance, Pitkin County Public Health’s epidemiologist, said, “Lower testing numbers play a small role in overall incidence, but our prevalence communitywide has decreased significantly, so the need for testing has also decreased.”

To determine whether testing is sufficient in the county, look at the positivity rate, Vance said, adding: “So long as it’s hovering around 5%, it generally tells us that we are testing enough people. Once it gets closer to 10%, it tells us that we’re likely missing cases and we need to ensure access to testing is available.”

The county’s positivity rate over the prior seven days, as of Feb. 11, was 3.9%, according to the state’s COVID-19 dial.

Lani Kitching works with a patient’s test sample at the testing kiosk in the cellphone parking lot near Aspen/Pitkin County Airport. Credit: Dan Bayer/Aspen Journalism

County received enough Curative tests to last through March

The FDA on Jan. 4 recommended that Curative tests be used only in symptomatic patients. Officials with the CDPHE said in an email that they do not have any estimate of how many false-negative results that Curative tests produced. False-negative results exist in all types of tests, the officials cautioned in an email.

According to Aspen Valley Hospital chief marketing officer Jennifer Slaughter, about 70% of those who received Curative testing were asymptomatic.

As of Jan. 19, the county has received 35,000 Curative tests from CDPHE, including 15,000 tests recently received as of that date that were supposed to maintain testing supplies through March 31, according to Senst. Just under 15,000 Curative tests had been used at the Pitkin County sites, including Aspen City Hall and through the Aspen School District’s testing program since the start of the pandemic, according to Senst.

Testing levels exceed recommended minimums

According to experts’ recommendations, communities should be able to process at least 152 tests per 100,000 people per day in order to help contain the coronavirus.

Pitkin County has about 17,700 year-round residents, but the peak-season population, including all tourists, second-home owners and commuting workers, reaches over 53,000 per day during the busiest times of the year, according to a 2020 estimate. Using that peak-season figure as the population benchmark, the county would need to be doing about 80 tests per day to meet the recommendation for minimum testing. With an average of about 250 tests per day over the past month and the capacity to do much more, the existing testing levels well exceed that minimum threshold.

Bailey O’Brien accepts COVID-19 test samples at a kiosk behind Aspen City Hall. Credit: Dan Bayer/Aspen Journalism

Aspen Valley Hospital’s role

Although it no longer runs any community testing sites, Aspen Valley Hospital is still processing PCR tests from BioFire and Cepheid on site with a doctor’s note. Results are received in less than an hour.

But since the BioFire and Cepheid tests are limited in supply, the hospital reserves them for patients with respiratory symptoms who are coming to the respiratory-evaluation center or the emergency department, or people who are being admitted to the hospital.

“We’re very careful about how we utilize those tests,” hospital CEO Dave Ressler said, since the facility can’t predict how many tests or kits they would receive from manufacturers.

The hospital also supports the county’s outbreak-containment efforts and will help process batches of tests from specific sites or large groups.

In early November, when the hospital was the main testing site in the Aspen area, it was processing roughly 45 tests a day. That number increased later in November — peaking to 78 per day — as the majority of the community’s testing began taking place elsewhere.

Over the past four weeks, the hospital has been doing an average of 33 to 39 tests per day, according to its dashboard.

“Today, we are able to get in all requests for testing in a day, and we do not have a backlog of people wanting to get tested,” Slaughter said Wednesday. “We are very much still supporting Pitkin County Public Health with outbreaks at specific sites and in large numbers.”

This story ran in the Feb. 13 edition of The Aspen Times.

Laurine Lassalle is Aspen Journalism’s data desk editor, where she works to catalogue and analyze local public data. She also heads our our “Tracking the Curve” project, documenting COVID-19 in Pitkin,...