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With 827 new coronavirus cases reported Monday, Utah’s rolling rate of new diagnoses continued to rise, passing 1,000 for the first time.

For the past week, the Utah Department of Health has tallied 1,001 new positive test results per day on average — continuing a streak of new record highs that began earlier this month as cases surged among young adults.

Since late August, the rate of new cases among patients ages 15 to 24 has more than tripled, from 98 per day to 342. 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. For the past week, with the average number of new cases per capita rising most rapidly among Utahns ages 25 to 44, and — with potentially deadly consequences — among those over 85.

Now the Utah Medical Association has joined some political voices and others in the health care industry in calling for a statewide mask order.

“There are a few things that we now know to be true that will help us control this pandemic and its devastating effects: one, that masks make a difference in the spread of the virus; and two, that we need to keep the economy open and moving forward and wearing masks will help us do that,” the association wrote in a letter last week to Gov. Gary Herbert. "While none of us like mandates, we feel in this instance that the benefits to the public far outweigh the inconvenience to the public.”

Utah’s death toll from the coronavirus stood at 453 on Monday, same as Sunday.

Hospitalizations were down slightly, with 167 Utah patients concurrently admitted. On average, 177 patients have been receiving treatment in Utah hospitals each day for the past week — continuing a two-week increase but still below the peak average of 211 patients hospitalized each day at the end of July.

Utah’s intensive care units were 64.6% occupied as of Monday, meeting the state’s goal of less than 85% occupancy. In total, 3,757 patients have been hospitalized in Utah for COVID-19, up 28 from Sunday.

The percentage of tests with positive results was at 14% — a rate that indicates a large number of infected people are not being tested, state officials say.

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

There were 6,212 new test results reported Monday, below the weeklong average of 7,916 new tests per day.

Cases spreading in Utah schools

State health officials updated Monday how they report school-related cases, showing totals by district and by age.

There were 1,955 cases linked to schools as of Monday, with 960 of those within the past two weeks, the state reported. At least 281 teachers have been infected this term. Among students, cases were far most prevalent in high schools, which had per-student rates more than double those in middle schools and at least triple those in elementary schools.

The number of school-related cases marks a sharp increase from Sunday — but the state on Monday began including any patient who has spent more than 15 minutes in a school within two weeks of symptoms developing, said Health Department spokesman Tom Hudachko; before Monday, the state was including only cases where the patients were in contact with at least one other confirmed case in a school. There were 770 such cases as of Sunday.

At least 14 schools in four districts have identified at least 15 cases in the past two weeks. Six of those schools have closed in accordance with state recommendations. The other eight remain open on modified schedules, with students attending fewer than five days a week.

The Alpine School District, the largest district in the state, had the highest number of cases, reporting 419 as of Monday. The district identified four high schools with at least 15 cases each; none of those schools had closed.

High case rates expanding through Utah, Salt Lake counties

The virus continued to spread quickly in Utah County, which recorded 356 new cases Monday — the most of any county or health district in the state. For the past seven days, Utah County has averaged 67 new cases a day per 100,000 people, more than double the statewide average of 31. County officials have implemented a mask order, and Herbert moved Provo and Orem up to the orange, or moderate, restriction level.

Brigham Young University, which has experienced the worst campus outbreak since fall term began, reported 1,328 cases as of Saturday, up from 1,272 cases Friday. Utah Valley University reported 233 cases as of Friday, up from 198 the week before.

Meanwhile, Salt Lake County tallied 295 new cases Monday, with a seven-day average of 32 new daily cases per 100,000 people.

Small-area case numbers, reported by the state, show Utah’s worst outbreaks still are in Provo and Orem — an area gaining about 95 new cases each day for every 100,000 people living there. Herbert said that rate would have to dip below 35 for him to consider moving restriction levels back to yellow, which would allow bigger gatherings.

But more and more communities in Utah and Salt Lake counties are reporting new cases at rates higher than Herbert’s threshold of 35. As of Monday, all of Utah County north of Spanish Fork was averaging more than 35 daily cases per 100,000 residents — even cities like Eagle Mountain and Saratoga Springs, which are separated from the university towns by Utah Lake. New cases were more prevalent in Alpine and Pleasant Grove than in some parts of Orem and Provo.

And now it appears the surge is spilling into southern Salt Lake County. Draper has for a couple of weeks posted new case rates on par with much of northern Utah County, with Salt Lake City’s downtown and hard-hit Glendale neighborhoods also reporting high numbers.

Now the data shows that Herriman, West Jordan, Copperton, South Jordan, Kearns, western West Valley City and eastern Sandy also are averaging more than 35 new cases per 100,000 people.

In fact, more than 975,000 Utahns live in cities where the virus is at least that prevalent, according to state data.

Although the Utah Medical Association and the Utah Hospital Association have called on Herbert to impose a state mask order, the governor has said he does not want to require masks statewide because some communities have lower infection rates than others.