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Another 747 Utahns have tested positive for COVID-19, the most in one day since Pioneer Day, the Utah Department of Health said Wednesday. And the spike comes, too, with the biggest single-day jump for cases tied to schools.

The state’s rolling seven-day average for new cases — the metric public health officials use to gauge trends — is now up to 585 cases per day. A week ago, that average was 404 per day.

Additionally, the percentage of positive test results statewide was a record 11.1% on Wednesday, topping the previous record of 10.6% on Tuesday, UDOH said in its daily report. A low percentage of positive tests indicates most infected people are being tested, along with a lot of uninfected people, state epidemiologist Dr. Angela Dunn has explained, noting that a 3% positivity rate would indicate the virus is under control.

But only 4,119 tests for the virus were processed in the past 24 hours, UDOH said. That’s well below the capacity of the 7,000 tests a day Utah’s labs were processing this summer.

And, overall, UDOH hasn’t reported this many cases in a day since July 24, Pioneer Day, when the daily tally was 863 cases. From June 25 to July 30, the seven-day average was above 500 cases per day, peaking at 669 a day on July 22.

Utah is “currently experiencing a new spike in cases, similar to what we saw earlier in the summer,” Dunn said in a statement. She reiterated that “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.”

By taking those steps, Dunn said, “we can prevent unnecessary death and illness.”

Meanwhile, one more Utahn was added to the state’s death toll, bringing the tally to 437 people. The person who died was a Salt Lake County man, older than 85 and not hospitalized at the time of his death.

The state has attributed much of the recent spikes to schools reopening. And on Wednesday, UDOH reported the highest numbers of school-related cases — 48 — for a single day since students were welcomed back to the classroom beginning Aug. 13.

The previous record was 36 cases, reported Monday. Overall, that brings the total cases in schools this fall to 293.

The state data doesn’t distinguish between K-12 schools and universities. But the virus has been spreading at both. Since reopening, there have been 48 outbreaks throughout education campuses in the state, with one new outbreak listed Wednesday.

For K-12, Canyons School District has the highest total cases in Salt Lake County. As of Wednesday, it was at 101. And it has had one high school — Corner Canyon in Draper — surpass 15 active cases. That’s the threshold the state has recommended for a school to temporarily move classes online again. But Canyons District has decided not to do that; it’s instead holding classes both online and in person, in a hybrid model, until Sept. 25.

Both Jordan and Granite districts have 99 cases each. One high school in Jordan — Riverton High — has also surpassed 15 cases.

During an interim legislative meeting Wednesday, Sydnee Dickson, the state superintendent for public schools, said she’s optimistic that the spread in K-12 has remained fairly low. Most administrators, she added, were holding their breath about reopening, but she believes it’s gone well so far.

Some issues remain, Dickson acknowledged, in getting all students to log in — if they’ve elected to do school online — and there has been some trouble with finding substitutes. She also said there has been a bit of pushback on the mask mandate in schools.

“It’s been very frustrating to deal with the polarization of mask wearing," Dickson said.

Dunn also spoke during the meeting and said she’s worried about the climb in virus cases among the state’s youths, ages 1 to 24. Even if kids don’t get seriously ill from the virus, she said, they likely bring it home to older parents and grandparents.

One of the biggest contributors to school cases has been Brigham Young University in Provo, which had 560 cumulative cases this fall as of Tuesday. It has 43,000 students and faculty. The spike came after it previously reported 258 cases Friday, giving it the highest total and fastest spread.

Utah County, overall, led the state in new cases, posting 309 Wednesday, a new single-day record for the county. That represents 41% of Wednesday’s new cases, even though Utah County contains about 20% of the state’s population. Utah County’s seven-day rolling average of new cases is 226.7 per day.

And Salt Lake County, the state’s most populous, recorded 272 of Wednesday’s new cases, the most in a day since July 25 — in the middle of the summer surge. Salt Lake County’s seven-day average of new cases is 211.1 per day.

The University of Utah in Salt Lake City, meanwhile, has had 241 cases for a campus of 62,000. It’s the second highest of the colleges in the state.

With the cases in all schools in the state, the patients have a median age of 16. Nine have been hospitalized; none has died.

As of Wednesday, there were 115 people hospitalized in Utah with COVID-19, including 20 admitted since the previous day. Since the pandemic began, 3,381 Utahns have been hospitalized with COVID-19.