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With 877 new coronavirus cases reported on Wednesday, Utah’s rate of new diagnoses continued to rise. And yet another new record for the percentage of tests that are positive suggests that an increasing number of infections are going undetected, health officials have said.

For the past seven days, Utah has averaged 876 new positive test results per day — far exceeding July’s top weeklong average of 671 new daily cases, the Utah Department of Health said.

Although the state had not updated its coronavirus “response scoreboard” for at least 10 days, it appears that some of the health measures have strayed farther from the goals set in Gov. Gary Herbert’s latest “accountability” plan. The goals include keeping weeklong averages to fewer than 400 new cases per day — a target Utah met in mid-August but surpassed again on Sept. 3 as cases among young adults exploded.

The state’s key metric under Herbert’s plan — a coronavirus death rate of less than 1% — stayed at 0.7% on Wednesday, possibly driven down by the large number of new cases among young and lower-risk patients.

Since late August, the rate of new cases among patients ages 15 to 24 has more than tripled, from 98 new cases per day to 338 new cases per day as of Wednesday. During the first week of September, the age group overtook 25- to 44-year-olds as Utah’s biggest contributor of new cases, despite comprising a far smaller portion of the state’s population.

But the group’s share of new infections began to drop last week as cases among the state’s other age groups began to rise sharply — about two weeks after the initial spike among teens and college-age adults.

Utah’s death toll from the coronavirus stands at 444, with one fatality reported since Tuesday: a Salt Lake County woman, older than 85, who was not hospitalized when she died.

Hospitalizations continued to rise on Wednesday, with 171 Utah patients concurrently admitted, UDOH reported. On average, 144 patients have been receiving treatment in Utah hospitals each day for the past week — continuing a two-week increase, but below the peak average of 211 patients hospitalized each day at the end of July.

Utah’s intensive care units were 68% occupied as of Wednesday, meeting the state’s goal of less than 85% occupancy. In total, 3,584 patients have been hospitalized in Utah for COVID-19, up 34 from Tuesday.

The virus continued to spread quickly in Utah County, which recorded 367 new cases Wednesday — the most of any county in the state. For the past seven days, Utah County has averaged more than 59 new cases a day per 100,000 people, more than double the statewide average of 27.

The county implemented a mask order on Tuesday, and under an order from Herbert, Provo and Orem will switch from the “yellow,” or low, restriction level, to “orange,” or moderate, Wednesday night.

Herbert has said the raised restriction level was due to elevated cases in those two cities. But new county data show many other cities in Utah County are recording similarly high numbers.

As of Tuesday, Provo was averaging 108 new cases daily per 100,000 residents, by far the highest rate in the county. But with a rate of 63 cases per 100,000 people, Orem recorded a lower prevalence of the virus than did Vinyard, Lindon and Cedar Hills.

Meanwhile, Herbert has said Provo and Orem must drop to fewer than 35 cases per 100,000 residents — a threshold that Mapleton, Alpine, Lehi, American Fork, Pleasant Grove, Saratoga Springs, Eagle Mountain, Highland, Santaquin and Springville also surpassed as of Tuesday.

Brigham Young University, which has experienced the worst campus outbreak since fall term began, reported 1,014 cases as of Monday, up from 927 on Sunday. Utah Valley University reported 198 cases as of Tuesday, up from 128 a week earlier.

Salt Lake County reported 320 new cases on Wednesday, with a weeklong average of 28 new daily cases per 100,000 residents. Infections appear to be most prevalent in Draper, which was averaging 53 new daily cases per 100,000 people as of Tuesday. It has not seen its restriction rating change from yellow, despite exceeding the state’s threshold for cases per capita.

No other city in Salt Lake County averaged more than 35 cases per 100,000 population.

The rate of tests with positive results statewide was at 14.2% on Wednesday, up from Tuesday’s 13.9%. State epidemiologist Dr. Angela Dunn has said the higher the percent of positive tests becomes, the likelier it is that a growing number of infected patients are going untested. She has said a 3% positivity rate would indicate the virus is under control.

Statewide, Utah’s rate of positive tests has been above 5% since May 25, according to UDOH data.

There were 6,899 new test results reported on Wednesday, above the weeklong average of 6,590 new tests per day. Testing demand has been rising in the past week or so but remains slightly below mid-July, when the state was reporting more than 7,000 new test results per day, on average.

Since public schools began opening on Aug. 13, there have been 78 outbreaks in schools, affecting 602 patients, with eight new outbreaks and 83 new cases reported in the past day — the largest jump in school-related cases in a single day.

Since the beginning of the pandemic, there have been 647 patients infected in 89 school outbreaks, with a median age of 16. Thirteen of those patients have been hospitalized, one within the past day; none have died.

Of 65,921 Utahns who have tested positive for COVID-19, 52,357 are considered “recovered” — that is, they have survived for at least three weeks after being diagnosed.