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A decline in coronavirus tests appears to be due to lower demand from patients, Utah health officials said on Wednesday, after new test results amounted to less than half of the state’s capacity for the second day in a row.

But it’s not clear why apparently fewer patients are seeking tests, said state epidemiologist Angela Dunn.

“We're trying to figure that out,” Dunn said. “We have all this capacity that we've built up, and testing is a huge part of solving this pandemic.”

As of Wednesday, 36,116 patients in Utah had been tested for coronavirus — 1,469 more than the state reported Tuesday. And on Tuesday, only 1,253 new tests were reported.

That’s less than half of the tests reported on most days last week, and far below the state’s total lab capacity to process more than 4,000 tests per day. Employees at ARUP Laboratories in Salt Lake City have confirmed that the volume of incoming tests has gone down in recent days.

“This time of year is warmer, and typical respiratory viruses are decreasing,” Dunn said. “I think there are less symptomatic people out there than in February. It is possible that there's just less demand.”

From Monday, March 30, to Sunday, April 5, the number of daily tests topped 2,000 on five days and topped 3,000 on two of those days, with a peak at 3,795.

Since March 23, state guidelines have made testing available to anyone with symptoms: cough, shortness of breath, or fever. “We’re working with our teams to really push the message that if you’re symptomatic, get tested,” Dunn said.

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But some Utah patients have reported being denied tests despite experiencing some symptoms.

Cami Prows Kanda called a West Jordan emergency room to ask about testing after she developed a fever and a dry cough about two weeks ago. A nurse told Kanda to stay home unless she developed severe shortness of breath.

Kanda said she holed up in her room and gradually began to feel better — but now she wonders about the accuracy of the state’s case numbers. Several others told The Salt Lake Tribune they had been denied tests or witnessed others being denied tests in recent days at various Utah health care facilities, despite the presence of at least one symptom.

“I don’t know how they will ever know the real number of people with it or [who] had it because we’re not all being tested,” Kanda said.

The reason for those denials isn’t clear, Dunn said; Utah’s hospital systems have coordinated with labs and public health officials to set the testing criteria and have been promoting tests in recent weeks, reversing earlier messages that people with symptoms should not seek tests because supplies were too limited.

Intermountain Healthcare, for example, opened 20 testing sites statewide last week and tested 13,000 people — compared to 6,000 people tested the previous week, said Jess Gomez, Intermountain spokesman.

“The fact we more than doubled the number of tests performed last week is indicative of the desire to test as many Utahns as possible,” Gomez said.

Traffic at Intermountain’s test sites dipped during the weekend, Gomez said — possibly due to The Church of Jesus Christ of Latter-day Saints’ General Conference, doctors guessed. Testing volume has been “steady” since Monday but still less than last week, Gomez said.

On average, Intermountain conducts about 1,300 tests per day, or 63 percent of all the tests in the state, Gomez said. “Whenever there’s advertising or news on this we tend to get surges,” Gomez said.

That’s consistent with testing data so far, which shows the number of tests swinging by more than 1,000 patients from day to day.

Utah still has tested a bigger portion of its population than most other states. According to The COVID Tracking Project at https://covidtracking.com/data, only seven other states have completed more testing per capita as of Wednesday.

But as the number of test results has dropped in recent days, so has the number of confirmed cases. As of Wednesday, the state had diagnosed 1,846 Utahns with coronavirus, up 108 from Tuesday. Of those, 158 have required hospitalization and 13 have died.

Inconsistent testing can make it difficult to guess what will happen next. A model developed by researchers at the University of Utah projects cases in the state could peak at the end of this week — but it doesn’t include the most recent, lower increases in cases because of the low number of tests.

The model is based on the spread of coronavirus in Italy, adjusted to the beginning of Utah’s outbreak. That’s defined as at least one new case on two consecutive days, which occurred in early March, or 23 days after the start of Italy’s outbreak in February, said biostatistician Fares Qeadan, part of the team that prepared the U. model.

That puts Utah's projected peak at April 10, when an estimated 250 new cases could appear, according to the team's forecast.

The highest single-day increase so far was on April 4, when state health officials announced 182 new confirmed cases.

New confirmed cases are likely to remain high next week, according to the model, which puts a smaller subsequent peak at April 15, with about 230 cases.

Stay-at-home orders and school closures can affect the spread, Qeadan said. But containment measures in the U.S., like compulsory social distancing, have generally aligned with the timing of similar measures in Italy, he said.

A peak in new cases on Friday would not mean Utah is home free after that, Qeadan warned. In an epidemic, the number of new cases tends to take longer to decline than it does to rise.

The Utah model is more optimistic than it was two weeks ago, when Italy’s new cases still apparently had not peaked and U. statisticians anticipated 70,000 cases over the duration of the outbreak. Now, with Italy’s new cases on a halting decline, the model projects 10,000 cases.