SALT LAKE CITY — Utah health officials reported another 747 COVID-19 cases — the highest daily increase since July — and another death on Wednesday.

Dr. Angela Dunn said this new spike shows people need to be reminded about the importance of following the same basic health directions.

“We learned from our experience this summer that wearing masks and practicing physical distancing, along with staying home when we’re sick and washing our hands regularly, can help slow the spread of COVID-19 in our communities,” Dunn, epidemiologist with the Utah Department of Health, said in a statement.

“We are currently experiencing a new spike in cases, similar to what we saw earlier in the summer. It’s time to reiterate the importance of people taking these preventive measures. By wearing masks, physically distancing, and staying home if we are sick, we can prevent unnecessary death and illness,” she said.

As infections continue to rise with K-12 and colleges resuming, a relatively new form of COVID-19 testing is becoming more popular as sports teams and high-risk sites like nursing homes use it to identify and track outbreaks faster.

Antigen testing

Like PCR tests, antigen tests are administered through a nasal swab. But instead of searching for the virus itself, antigen tests detect proteins found on the virus. While patients usually wait up to several days to receive PCR test results, antigen tests can return results in 15 minutes.

The Centers for Disease Control and Prevention says the method of testing is less sensitive than PCR testing, however. Antigen tests are at their most accurate at the early stages of infection when viral loads are highest, according to the CDC.

“Antigen tests are very accurate. However, there is a higher chance of having a false negative test result. This means if you test negative for COVID-19 with an antigen test, you may also need to get a PCR test to make sure you don’t have COVID-19,” according to the Utah Department of Health.

Because of the higher false negative rate, when someone gets an antigen test, officials encourage their provider to also consider their symptoms and possible exposures. A patient who tests negative for the disease with an antigen test should receive a follow-up PCR test if they are symptomatic or have a known exposure to a confirmed COVID-19 case, the CDC says.

The effectiveness of antigen tests as a public health tool is also limited due to inconsistent reporting of test results across states — 20 states don’t report antigen test results or count positives as confirmed cases.

Utah, however, includes both PCR and antigen positive and negative results in its case totals. The methods of testing are broken out on the state health department’s COVID-19 dashboard in the section titled “COVID-19 Cases by Positive Test Report Date.” The small portion of positive antigen results are shown in green, and negative antigen results are shown in black. The numbers are so small that they’re easy for the eye to miss.

Although the public in Utah has access to antigen tests — some private clinics and independent testing companies administer them — the state doesn’t have a good way of tracking and disseminating information about where patients can get antigen tests, noted Jenny Johnson, spokeswoman with the Utah Department of Health.

But Utah is now purchasing rapid-testing machines to deploy to high-risk facilities, nursing homes, Native tribes and local health departments so that they can provide antigen testing on site as needed with quick turnaround times, Johnson said.

Although they’re faster, antigen tests won’t replace PCR tests.

“If we can have a less invasive test that’s just as accurate as a PCR, if turnaround times are quicker, we want to build that capacity and support that, but it’s not pitting one against the other. They serve different purposes and there’s pros and cons to both of them,” Johnson said.

The federal government has also started relying on antigen tests to test nursing home patients and contain outbreaks. The Department of Health and Human Services awarded a $760 million contract to buy 150 million rapid antigen tests from Illinois-based diagnostics company Abbott.

On May 9, The Food and Drug Administration approved the first antigen test for COVID-19. On Aug. 26, the FDA approved an antigen test developed by Abbott that shows results directly on a testing card, similar to a pregnancy test. That test must be given within seven days of symptom onset.

Turnaround times of PCR tests in Utah average between 24 and 48 hours — but that is subject to change based on demand, Johnson said. The state continues to maintain its testing capacity at 7,000 to 8,000 per day, but fewer people have sought testing for the past several weeks.

“The published turnaround time for COVID-19 diagnostic testing is one to four days, although ARUP is able process many tests that originate in Utah in about 36 hours,” Adam Barker, director of ARUP’s COVID-19 Rapid Response Lab, said in a statement to the Deseret News.

Utah is also continuing to grow its overall testing capacity.

Officials with ARUP Laboratories confirmed Tuesday the lab soon expects to increase its capacity to process up to 15,000 COVID-19 PCR tests daily. ARUP, which partners with University of Utah Health, is not performing antigen testing and does not have plans to do so, officials said.

Intermountain Healthcare and TestUtah, two of the other large test providers in Utah, are also not performing antigen tests for the public. Antigen testing is, however, being used for COVID-19 symptomatic patients in the emergency departments and labor and delivery centers at Intermountain, officials said.

New cases

Wednesday’s coronavirus cases were confirmed out of 4,119 tests, with an 18.1% positive rate. They bring the state’s total cases since the pandemic began to 59,747 of 729,731 people tested, an overall positive rate of about 8.2%.

The rolling seven-day average for new cases is now 585 per day, and the average positive test rate is 11.1%. Currently, 115 patients are hospitalized with COVID-19 in Utah, 13 fewer than on Tuesday. Since the beginning of the outbreak, 3,381 people in Utah have been hospitalized with COVID-19.

Utah County’s cases — 41% of the total — again surpassed Salt Lake County’s on Wednesday.

A high percentage of Utah’s new cases are in the 15-24 age group as college has resumed. That group accounted for 38% of the state’s new cases on Wednesday, health officials noted.

On Tuesday, Utah Valley University updated its self-reported case count to 151 students and 47 staff and faculty members, while Brigham Young University self-reported 330 active cases and 230 cases no longer in isolation. The University of Utah has confirmed 241 cases on its campus as of Tuesday.

The death reported Wednesday was a Salt Lake County man older than 85 who was not hospitalized when he died. His death brings the state’s death toll to 437.

About 49,700 of Utah’s cases are considered recovered after surviving the three-week point since their diagnoses, meaning about 9,600 cases remain active.

New COVID-19 cases reported Wednesday by health district across Utah:

  • Utah County, 309.
  • Salt Lake County, 272.
  • Davis County, 46.
  • Bear River (Box Elder, Cache, Rich), 38.
  • Weber-Morgan, 37.
  • Southwest Utah, 23.
  • Tooele County, 7.
  • Wasatch County, 6.
  • Central Utah, 4.
  • Summit County, 2.
  • TriCounty (Uinta Basin), 2.
  • Southeast Utah, 1.
  • San Juan County, 0.