Dan Howe expected his COVID-19 test would feature a quick but jarring poke deep inside his nasal cavity.
When a doctor swabbed the back of his throat instead, Howe was startled — not by the collection itself, but the idea of it.
"I was expecting a nasal swab," said Howe, 60, of Anoka, who was tested this month by Allina Health System in Minneapolis. "Anyone who's had a throat culture taken, they kind of know what it's like. It's not painful at all."
Doctors are trying new approaches to collecting specimens for COVID-19 tests as the growth in testing means more patients must endure nasopharyngeal swabs that are widely used to collect samples. The swabs are long in order to reach where the nasal cavity meets the throat, so the procedure can be uncomfortable.
"It feels more like a brain biopsy in that the swab goes quite deep," said Dr. Eric Rubin, editor-in-chief of the New England Journal of Medicine, in a podcast this month. Rubin's comments accompanied study results in the journal from researchers at Minnetonka-based UnitedHealth Group that suggest patients could use shorter swabs to collect samples from different parts of the nose.
On Sunday, the Minnesota Department of Health reported a one-day tally of 12,289 completed COVID-19 tests, a fifth consecutive day that's exceeded 10,000 results. Net confirmed cases grew by 461 on Sunday, including 13 more in Mower County.
Organizers of a large testing event this past weekend in Mower County opted for shorter swabs after some people stayed away from a previous event because of concerns about discomfort, said Pam Kellogg, division manager for health and human services. Mower County, which is about 100 miles south of the Twin Cities, has seen cases spike in recent weeks due in part to outbreaks at meat-packing plants.
"It should be much more comfortable," Kellogg said last week.
The Health Department on Sunday reported eight more deaths, bringing the statewide toll to 1,380. All of the newly reported deaths were among long-term care residents. The latest numbers continued a trend in recent weeks of lower daily counts for new deaths and cases in Minnesota.
Earlier this year, a large medical group near Seattle reported success in detecting the virus that causes COVID-19 when patients used two different types of shorter swabs to collect their own nasal specimens. The medical group is owned by UnitedHealth Group, which mobilized resources to help doctors at the Everett Clinic test the alternate methods on hundreds of patients.
In their study, health care workers guided patients as they used the shorter swabs. Workers then used nasopharyngeal swabs to collect specimens, so researchers could compare results with different methods. They concluded the alternative methods were sensitive enough to provide clinicians with a "useful approach," according to results published this month in the New England Journal of Medicine.
"This does look like a fairly reproducible, fairly sensitive way of testing, which is much more convenient and less expensive than the approach we're using now," Rubin said in a podcast about the study. "This sort of approach really could change how available testing is and how we put testing into any algorithm for reopening."
The editors noted that no testing method is 100% accurate. The UnitedHealth Group study found self-administered swab tests accurately detected COVID-19 in more than 90% of positive patients.
Nasopharyngeal swabs are considered the gold standard when it comes to testing for COVID-19, because the virus that causes the ailment is thought to infect cells at the back of the nose, said Dr. Timothy Schacker, vice dean for research at the University of Minnesota Medical School.
Swabs that don't reach as far back result in tests that probably aren't as sensitive, Schacker said, which means there's a chance some might not detect infections. But the alternative methods have advantages, he said, in terms of patient comfort and self-administration. Plus, health care workers use more personal protective equipment (PPE) when using nasopharyngeal swabs, Schacker said.
"Our next goal is to get a test that's as sensitive as can be, but can be done on something that's easily collected and doesn't require PPE," he said. "As you make it easier to collect and you bring down the cost, maybe that changes the balance of the equation of how often do you test and what makes the most economic sense for putting this test in play."
COVID-19 is a viral respiratory illness. Since the first case was reported in Minnesota in March, 32,920 people in the state have tested positive.
After UnitedHealth Group released preliminary results of its study this spring, the Food and Drug Administration updated its guidance on collection methods based on the research. At Bloomington-based HealthPartners, most patients are still being tested with nasopharyngeal swabs, but shorter nasal swabs are now in the mix, said Dr. Mark Sannes, an infectious disease specialist.
"As everything else goes with COVID, the science continues to evolve," Sannes said.
Nasopharyngeal swabs are still preferred at Mayo Clinic, but the clinic is particularly interested in a type of swab called "mid-turbinate" that also was evaluated in the UnitedHealth Group study. That particular swab is manufactured by only one company, so centers are experimenting with whether they can use 3-D printers to create a supply, said Dr. Bobbi Pritt, a professor of laboratory medicine and pathology at Mayo Clinic.
Testing clinics at Allina Health System have generally relied on nasopharyngeal swabs but recently started collecting specimens from the back of the throat, said Heather Dawson, vice president for laboratory services at Allina. That approach was not evaluated in the UnitedHealth Group study.
Switching the method for swabbing patients might sound easy, but many health care providers stick with the swabs that are included in testing kits by manufacturers, Dawson said. In addition, labs like the one at Allina run tests to independently validate that any specimen collection method works with their machinery.
Allina hasn't finished all tests with the new back-of-the-throat method, Dawson said, but the results so far suggest comparable results to the nasopharyngeal swab.
"When we're finished we will use both and it won't be because one is better than the other — it will be because of what we can get our hands on to actually do testing," she said. "We're all struggling with [supplies of] media and swabs, and so the more access to things that provide accurate results, the better off we are."
People at greatest risk from COVID-19 include those 65 and older, residents of long-term care facilities and those with underlying medical conditions. The medical conditions range from lung disease, serious heart conditions and cancer to severe obesity, diabetes and kidney patients who need dialysis.
Most cases don't result in serious illness. The number of Minnesotans hospitalized with COVID-19 continued to decline on Sunday, with 322 patients in the hospital, including 160 in intensive care
Christopher Snowbeck • 612-673-4744