Milwaukee Journal Sentinel

In­side

- Lo­cal, 3A

Rapid tests may help fight surge, but they have draw­backs.

Only about 3% of the COVID-19 tests taken by Univer­sity of Wis­con­sin-Oshkosh stu­dents are com­ing back pos­i­tive. In the city that sur­rounds them, the rate is sev­eral times as high.

The school’s top test­ing official thinks that shows the school’s test­ing ap­proach — us­ing rapid anti­gen tests to reg­u­larly test stu­dents — is work­ing.

Now, through a first-of-its kind part­ner­ship be­tween UW Sys­tem schools and the U.S. Depart­ment of Health and Hu­man Ser­vices, these free rapid tests are be­ing rolled out to the broader com­mu­nity.

Can they help rein in ram­pant spread in places like the Oshkosh-Neenah metro area, which as of Thurs­day ranked among the 20 U.S. metro ar­eas that had seen the most cases per capita, ac­cord­ing to The New York Times? Ex­perts say they might, but rapid tests have their draw­backs, too.

UW-Oshkosh tests 2,400 stu­dents weekly from res­i­dence halls and offcam­pus hous­ing us­ing anti­gen tests, which de­tect cer­tain pro­teins in the novel coro­n­avirus. At about $23 apiece, they’re cheaper than PCR tests, which look for the pres­ence of the virus’ ge­netic ma­te­rial and can run over a hun­dred dol­lars each.

Im­por­tantly, the anti­gen tests pro­duce faster re­sults — UW-Oshkosh stu­dents get re­sults back in an hour, while Wis­con­sinites who visit a Na­tional

Guard test­ing site in the state typ­i­cally wait three to seven days, ac­cord­ing to news re­leases is­sued by lo­cal sites.

Speed is of the essence to con­trol out­breaks with test­ing. Even a three­day de­lay be­tween symp­tom on­set and re­ceiv­ing re­sults can cut in half the num­ber of fu­ture trans­mis­sions that can be pre­vented with con­tact trac­ing,

a July study in The Lancet showed. Plus, it’s eas­ier to put life on hold for an hour while wait­ing for re­sults than for sev­eral days.

HHS has shipped more than 600,000 of the anti­gen tests to Wis­con­sin nurs­ing homes and as­sisted liv­ing

fa­cil­i­ties, and an­nounced Oct. 26 that 1.8 mil­lion anti­gen tests were en route to Wis­con­sin to help K-12 schools stay open and health care work­ers and first re­spon­ders get back to work faster af­ter an ex­po­sure.

And most re­cently, they sent 250,000 more to UW Sys­tem cam­puses to pi­lot a specific test that can de­liver 15minute re­sults to any­one who wants them.

With anti­gen tests more widely avail­able across Wis­con­sin, hopes are high that their speedy re­sults could help tamp down the state’s surge in cases.

“Ev­ery­body’s won­der­ing if this can be the new sav­ing grace,” said Alana Sterkel, an as­sis­tant di­rec­tor at the state hy­giene lab who ad­vises Wis­con­sin’s emer­gency op­er­a­tions staff on lab test­ing.

That in­cludes the White House Coro­n­avirus Task Force, a group of top fed­eral officials who au­thor weekly re­ports about how each state is far­ing with the pan­demic. In Wis­con­sin’s Nov. 8 re­port, which de­scribed the state’s “un­re­lent­ing rise” in cases and test pos­i­tiv­ity rates, they wrote that ex­panded and strate­gic use of the anti­gen tests should be used to con­trol the surge.

The re­port men­tions neigh­bor­ing Minnesota, where Gov. Tim Walz rolled out a mas­sive test­ing ini­tia­tive of asymp­to­matic 18- to 35-year-olds on Oct. 28, us­ing the quick-turn­around tests, to bet­ter gauge how the virus is spread­ing among that age group. Details about the ini­tia­tive are scarce, but Walz told re­porters that the in­stant re­sults can “start to break” their surge.

At UW-Oshkosh, Cen­ters for Disease Con­trol and Preven­tion re­searchers are try­ing to find out if the anti­gen tests can de­liver what’s be­ing asked of them. They launched a study Mon­day of the school’s surge site, said Kim Lan­golf, who over­sees risk man­age­ment for the cam­pus and has led its test­ing ini­tia­tives.

If the site pro­duces suc­cess­ful re­sults, the method could ex­pand across the state and na­tion. The CDC did not re­spond to a re­quest about when re­sults would be known and what key mea­sures re­searchers are ex­am­in­ing.

Even be­fore the com­mu­nity site open­ing, though, Lan­golf said the fact that the cam­pus has held its test pos­i­tiv­ity rate so low proves the rapid strat­egy they’ve de­vel­oped is effec­tive.

“We know our stu­dents very well and we know that this age de­mo­graphic can be difficult to get in to test,” Lan­golf said. “(We knew) the more efficient and quick we could be, the bet­ter com­pli­ance we would have.”

But the cam­pus has some tools that the com­mu­nity doesn’t. The key one?

Lever­age. They can re­quire stu­dents show up for their weekly test — and many do, with more than 95% com­ply­ing, Lan­golf said. Schools can over­see stu­dents’ iso­la­tion or quar­an­tine pe­ri­ods, and on the front end, they can re­quire them to wear masks and prac­tice phys­i­cal dis­tanc­ing.

Fre­quency is crit­i­cal, es­pe­cially be­cause anti­gen tests are less sen­si­tive than PCR tests. The CDC rates PCR tests as hav­ing “high” sen­si­tiv­ity, while anti­gen tests are “mod­er­ate,” mean­ing more cases of disease might be missed with the lat­ter. An anti­gen test may not pick up trace amounts of the virus on the first try, Lan­golf said, which is why it’s im­por­tant the stu­dents come back week af­ter week.

As the tests be­come more widely avail­able, Sterkel, with the state lab, said she’s heard sug­ges­tions to put them in den­tist’s offices, in work­places or even at home.

But the tests aren’t yet high enough qual­ity and can’t be eas­ily per­formed by the non-pro­fes­sion­als. Even seem­ingly mi­nor mis­takes — like not fol­low­ing the in­struc­tions of the test, not fol­low­ing safety pro­ce­dures or con­tam­i­na­tion of sur­faces on which pa­tient sam­ples are han­dled — could pro­duce false re­sults, she said.

The qual­ity of the test mat­ters more to Sterkel than any­thing else, she said, be­cause peo­ple need to be able to have confidence in their re­sults.

“If we have too many of these low­er­ac­cu­racy tests avail­able in un­reg­u­lated set­tings, we’re go­ing to see false re­sults and it’s go­ing to erode public trust in these tests,” Sterkel said.

The U.S. Food and Drug ad­min­is­tra­tion warned health care providers in a Nov. 3 let­ter that any de­vi­a­tion from the de­tailed in­struc­tions for a rapid test — like read­ing the re­sults be­fore or af­ter the specified win­dow of time — could pro­duce false pos­i­tives. Sci­en­tists and lab ad­min­is­tra­tors have crit­i­cized the fed­eral gov­ern­ment for not pre­sent­ing more clearly how the tests should be con­ducted.

Sterkel com­pares an anti­gen test’s use­ful­ness to preg­nancy tests: A per­son might get their first no­tification from two thin lines on a plas­tic stick pur­chased at the drug store, but most fol­low up with a doc­tor for confirma­tion.

She helped au­thor statewide guid­ance on how best to use the rapid tests, sug­gest­ing that both peo­ple who test pos­i­tive but don’t show symp­toms, as well as symp­to­matic peo­ple who test neg­a­tive, get a fol­low-up PCR test to confirm their re­sults. Later, the CDC rec­om­mended the same ap­proach.

UW Sys­tem Pres­i­dent Tommy Thomp­son said he’s proud of the low virus preva­lence on col­lege cam­puses and pleased they were cho­sen to beta-test the strat­egy.

He said he’d love to see them be the “suc­cess­ful ex­am­ple” that ul­ti­mately curbs Wis­con­sin’s spike in cases and leads to use around the coun­try.

The sites will pro­vide real-time data to the CDC to as­sess how well the test is per­form­ing and what cir­cum­stances it would be best used in. It would be nice to move from math­e­mat­i­cal mod­els to hav­ing ac­tual data in hand, Sterkel said.

Lan­golf isn’t sure that one test­ing ap­proach could be the thing that finally cuts off the virus’ ex­po­nen­tial growth. But she’s hop­ing the re­sults of the CDC study will prove some­thing.

“I think our com­mu­nity is suffer­ing so much that it’s go­ing to be hard to de­ter­mine what turns it around,” she said. “What we will know is how effec­tive and valid this ap­proach is.”

“If we have too many of these lower-ac­cu­racy tests avail­able in un­reg­u­lated set­tings, we’re go­ing to see false re­sults and it’s go­ing to erode public trust in these tests.”

 ??  ?? Clin­i­cal staff em­ploy­ees dress in per­sonal pro­tec­tive equip­ment in the Cul­ver Fam­ily Wel­come Cen­ter at the Univer­sity of Wis­con­sin-Oshkosh to ad­min­is­ter COVID-19 test­ing for the com­mu­nity with 15-minute turn­around time on re­sults.
Clin­i­cal staff em­ploy­ees dress in per­sonal pro­tec­tive equip­ment in the Cul­ver Fam­ily Wel­come Cen­ter at the Univer­sity of Wis­con­sin-Oshkosh to ad­min­is­ter COVID-19 test­ing for the com­mu­nity with 15-minute turn­around time on re­sults.

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