Minnesotans in close contact with COVID-19 cases should continue to seek diagnostic testing even in the absence of symptoms, despite new federal guidance that such testing is optional, state health officials said on Wednesday.

People can carry the novel coronavirus that causes COVID-19 without suffering symptoms and need to be identified before they spread it to others at greater risk of severe infections, said Kris Ehresmann, state infectious disease director.

“Our testing capacity is increasing and we need to use it in a manner that will help us identify cases quickly — and testing someone with a known exposure certainly is the most targeted way to do so,” she said.

The U.S. Centers for Disease Control and Prevention changed its guidance this week to indicate that testing was “not necessarily” needed for all asymptomatic people with moderate exposure risks. However, the CDC urged people in these situations to follow the guidance of their doctors or local and state health authorities, and to seek testing if they have conditions such as diabetes or heart disease that put them at elevated risk.

While limited capacity has been a problem at times, the state Health Department this summer has maintained its recommendation for testing of asymptomatic people if they spent 15 minutes within 6 feet of known COVID-19 cases.

Minnesota is at a sensitive juncture in the pandemic, with numbers stabilizing to a daily average of roughly 630 confirmed infections per day over the past two weeks. Hospitalizations have leveled off as well, with the state reporting 304 on Wednesday.

On the other hand, the reopening of schools and colleges is creating the potential for a new wave of cases.

“That’s always been the biggest problem with COVID — not knowing what comes next,” said Dr. John Hick, a Hennepin Healthcare physician who has led the coordination of Minnesota’s medical response to the pandemic.

“As school gets back in, I feel like we’re in a little bit of a steady state, but it’s at a higher level of cases than we want to see. ... That makes us nervous. We’re always just a few steps away from having this really take off.”

The state also reported 14 COVID-19 deaths on Wednesday, the third double-digit tally in two weeks after nearly two months of lower fatality counts. Total COVID-19 deaths in Minnesota have now reached 1,793.

The total count of known infections is now 71,236 — though that doesn’t include the number of asymptomatic people who may have spread the virus but never sought testing.

One reason for concern is that an all-time high of 38% of known infections in communities in Minnesota are coming from unknown sources. That is above the state’s target of no more than 30% and means the virus is spreading beyond the state’s ability to track it.

The state is falling short on three of five goals it uses to assess its pandemic response and what restrictions are necessary. New case and hospital admission rates also are above state targets.

The new CDC guidance seeks to reduce blanket testing in places where it is less useful and encourage “appropriate testing” of asymptomatic patients in states with surging case growth that need it, said Dr. Brett Giroir, an assistant secretary at U.S. Health and Human Services, at a news conference Wednesday.

Some medical leaders in Minnesota said the change in CDC guidance is ill-timed.

“Decreasing testing is 100% the wrong direction. Inexplicable,” said Dr. David Boulware, an infectious disease specialist at the University of Minnesota who has led COVID-19 clinical drug trials, in a tweet. “States, doctors, AND insurance companies will hopefully just ignore CDC guidance.”

The state has four free testing clinics set up through the end of August in Minneapolis, St. Paul, Bloomington and Maplewood in response to community-level outbreaks. It also is investing $14.6 million in new rapid saliva COVID-19 testing technology and a processing facility for those samples in Oakdale.

The CDC switch is understandable if it is preserving highly accurate nasal-swab diagnostic testing for a potential surge of cases after school resumes this fall, but ultimately more testing of all kinds is needed to track and respond to the pandemic, said Dr. Keith Stelter, a Mankato physician and president of the Minnesota Medical Association.

“We have to continue to test a lot and maybe even more frequently,” he said, “but we need another modality of testing to be able to preserve these supplies.”

An unchecked new wave of cases could hurt Minnesota’s health care system. The medical association released survey results Wednesday showing that 81% of physicians and 90% of clinic administrators worry about their facilities’ ability to withstand another wave if it results in reduced patient activity for other types of care or another state moratorium on elective procedures.

Gov. Tim Walz ordered such a moratorium this spring to preserve staffing and personal protective equipment for doctors and nurses treating highly infectious COVID-19 patients.

While Stelter said it was based on the best evidence at the time of how to slow the pandemic, the survey results showed consequences.

More than half of surveyed doctors said the resulting delays in care caused some harm in patients, including a few deaths. Stelter said a couple of his diabetic patients delayed treatment for circulatory complications to the point that they needed amputations of toes or feet.

“Hindsight always does show us some things that were maybe a bit too far-reaching,” he said, “but you know that was our best guess at the time. We were saying, ‘you know, we have to stop this before it totally gets out of hand.’ ”

Reports of COVID-19 cases among returning college students fueled concerns for state health officials. They have urged a “lay low” strategy of having students avoid large groups and high-risk situations in the two weeks before they return to their campuses to maximize their chances of showing up virus-free.

One positive sign came from a CDC assessment on Wednesday of COVID-19 levels at youth summer overnight camps in Maine, which imposed a variety of requirements on attendees, including universal testing, social distancing and mask-wearing. As many as 17 children from Minnesota attended these camps.

Testing of 1,006 attendees a week into the camps found three asymptomatic children with COVID-19. Those children were isolated, and close contacts quarantined, preventing any secondary cases.

The success contrasts with a CDC report last month from a camp in Georgia, where prevention strategies were not widely followed; 260 of 597 attendees tested positive.