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With 906 new coronavirus cases reported on Wednesday, Utah’s rate of new diagnoses continued to rise — and, with those cases added to the rest of the month, September has brought more new cases to Utah than any other month since the beginning of the pandemic.

However, the number of COVID-19 deaths in Utah was the lowest of any month since April.

For the past week, the Utah Department of Health has tallied an average of 1,017 new positive test results a day — continuing a streak of new record highs that began earlier in September as cases surged among young adults.

In total, the state reported 20,935 new cases in September, compared with 17,979 in July; 12,420 in June; and 11,911 in August.

In September, 52 Utahns died — half of the 104 who died in August, and fewer than half of July’s 134 deaths.

The lower death rate may be tied to the increasing representation of younger age groups among new cases. Meanwhile, patients age 65 and older in the latest surge may have gotten ill too recently to be represented in September’s fatalities; more than half of cases from the oldest age groups were diagnosed within the past 10 days, according to UDOH data.

Utah’s death toll from the coronavirus stood at 459 on Wednesday, with two fatalities reported since Tuesday: a Washington County man, older than 85; and a Davis County man, age 65 to 84.

The rate of new cases declined slightly in Utah County, which recorded 314 new cases Wednesday. But for the past week, the county still has averaged 65 new cases a day per 100,000 residents — the highest number of any county in the state, and more than double the statewide average of 32.

Brigham Young University, which has experienced the state’s worst campus outbreak since fall term began, reported 1,385 cases as of Monday, up from 1,349 cases as of Sunday. Utah Valley University, in Orem, reported 286 cases as of Tuesday, up 53 from its previous count, posted Friday.

Students from both colleges have teamed up to launch a public awareness campaign with the hopes of slowing the spread of the virus. It’s called “Join the Maskerade." And it’s meant to encourage young adults, who are currently making up the bulk of the new cases, to be part of “a fun citywide, socially-distanced party — you only have to wear a mask to get in," said Aubree Smith, a senior who worked on the project, in a statement.

Provo spent $100,000 on the campaign, which officially launches Thursday. The largely digital effort will continue for three months, and includes signing a pledge at JoinTheMaskerade.org that enters participants into drawings for prizes.

Meanwhile, hospitalizations were up significantly Wednesday, with 203 Utah patients concurrently admitted, UDOH reported. On average, 185 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.

In total, 3,847 patients have been hospitalized in Utah for COVID-19, up 40 from Tuesday. In the past two weeks, 466 hospitalizations have been reported — the highest 14-day total since the beginning of the pandemic.

Utah’s intensive care units were 66.5% occupied as of Wednesday, meeting the state’s goal to stay below 85% occupancy.

For the past week, 13.6% of all tests have come back positive — a rate that indicates a large number of infected people are not being tested, state officials have said. State health officials have said a rate of 3% or lower would indicate the virus was under control.

There were 8,106 new test results reported on Wednesday, above the weeklong average of 7,730 new tests per day.

Cases were on the rise in schools, where Utah officials tallied 2,262 total cases on Wednesday, up 166 from Tuesday. Of those patients, 1,088 were diagnosed in the past two weeks, which means they are considered “active,” or could infect others.

Since schools began opening in mid-August, there have been 318 teachers infected with the coronavirus — an increase of more than 20 in a single day.

With the rising cases, Salt Lake City School District announced Tuesday that it will continue with solely online instruction through at least the end of the first quarter of the academic year, which ends on Nov. 9. The district is the only one in the state that started with instruction entirely remote this fall.

The district said it will return students to classrooms in person if the average positivity rate in the greater county was at 5% of those tested. Currently, it’s at 11.6%. The district is also watching the cases per 100,000 people. To reopen, it will need to be below 10. Right now, it’s at 32.1. Those metrics have been increasing with the recent spikes.

“The priority of the Salt Lake City School District is the health and safety of our students, families, and employees,” wrote interim Superintendent Larry Madden in a message to parents about the decision.

Researchers from Intermountain Healthcare announced Wednesday they had developed new criteria to diagnose more accurately which COVID-19 patients suffer from an acute inflammatory process that hits when the body’s immune system overreacts to the virus. That process, in some people, can inflame patients' lungs and other organs — increasing the need of a ventilator or the risk of dying.

Poring over studies published since the first of the year and then crunching the numbers, the researchers developed a list of six criteria to measure the incidence of coronavirus-related inflammation.

The researchers then looked at the records of 299 COVID-19 patients, and found that patients that met at least two of the criteria were four times as likely to need a ventilator, said Dr. Brandon Webb, infectious disease physician and researcher at Intermountain. The six criteria are detailed in a paper, for which Webb is the lead investigator and author, that was published Tuesday evening in the medical journal The Lancet Rheumatology.

Dr. Samuel Brown, a critical care physician at Intermountain and another researcher on the study, said finding a patient’s “score” of those criteria can help doctors personalize trial treatments for patients more susceptible to this hyperinflammatory response to COVID-19, and it can guide future treatment in other populations.

The “score,” Webb said, “will help us target the right treatment to the right patient, early.”

— Tribune reporters Sean P. Means and Courtney Tanner contributed to this article.