Changes in COVID-19 activity in the next week could dictate the course of the pandemic in Minnesota and whether society can reopen beyond partly filled churches and restaurant service on patios, state health officials said Tuesday.

Cases of the infectious disease are expected to increase following the May 18 end of Gov. Tim Walz’s 51-day stay-at-home order. But it is unclear whether that will happen at a manageable pace or with a surge that challenges hospitals already seeing their intensive care beds fill up.

“We are in a pretty volatile phase in the curve,” said Jan Malcolm, state commissioner of health. “With these numbers going up and down, and [use of] hospital capacity seeming to … accelerate, we really feel like we need to keep a very close eye on the data.”

Statistical indicators offer differing takeaways. The 258 people with COVID-19 needing intensive care as of Tuesday was a record high for Minnesota so far in the pandemic, which has caused 899 deaths — including 732 deaths among residents at long-term care facilities.

At the same time, the number of days at which COVID-19 cases are doubling in Minnesota has dropped to 18, even as diagnostic testing has increased.

Health officials warned that it is too soon to assess any impact of ending the stay-at-home order. Even if that move increased face-to-face contact and disease transmission, the incubation period can last several days after infection before symptoms emerge.

Public adherence to social distancing could chart the direction of the pandemic, especially as people have more opportunities to interact with others — including the resumption of church services. An agreement brokered between clergy and Walz allows services for up to 250 people or 25% of building capacity beginning Wednesday. And bars and restaurants can begin service on patios Monday.

The next phase under consideration by Walz would be to allow indoor dining at restaurants, gradual reopening of public swimming pools, and doubling the limit on social gatherings to 20 people.

The state’s latest figures showed that 98% of COVID-19 deaths involved residents of long-term care facilities or people with underlying health conditions such as diabetes, asthma, or diseases of the heart, lungs, kidneys or immune system. However, Malcolm said the median age of diagnosed cases is 42 and that one of the 18 deaths reported Tuesday involved someone in their 40s.

“We do see severe disease and even deaths among younger people,” she said.

M Health Fairview officials appealed on Tuesday for people to wear cloth, nonmedical-grade masks because of the increasing evidence that this slows the spread of the novel coronavirus that causes COVID-19. Masks might not protect the wearers, but they prevent them from spreading the virus to others who might suffer more severe infections, said Dr. Abe Jacob, chief quality officer for M Health Fairview.

“This is an apolitical argument,” Jacob said. “This is a public health, public safety, keeping my kids, your parents, other people safe argument.”

People have received mixed messages, starting with health officials telling them not to wear any masks because they worried about running out of medical-grade masks that doctors and nurses need, Jacob said. Health officials also worried that mask-wearers would infect themselves by touching their faces, but recent studies have demonstrated a protective benefit.

State health officials said individual outbreaks reported across Minnesota, including in nine — perhaps now 10 — counties with food processing facilities, share a common concern: Workers often return home or visit relatives in other counties on weekends.

An outbreak in the Cedar-Riverside neighborhood of Minneapolis extends somewhat to workers in long-term care facilities bringing the virus back home.

“We recognize the connectedness of so many of the things we’re looking at,” said Kris Ehresmann, state infectious disease director.

The addition of 652 lab-confirmed COVID-19 cases on Tuesday brought the state total in the pandemic to 21,960 so far — including 2,427 health care workers.

As many as 80% of infections produce mild or no symptoms. Among diagnosed cases of COVID-19, 15,523 have recovered and are no longer required to isolate themselves to avoid spreading the virus.

The trouble with asymptomatic cases is that people can spread the virus without knowing it, Malcolm said.

Free testing for COVID-19 was provided at six National Guard armories over the weekend to more than 10,000 people — which Malcolm said was beyond projections.

While testing is usually reserved for people with symptoms, Malcolm said the testing at the armories included people with no symptoms, and that the results could offer another clue as to how many people carry the virus without knowing it.

No vaccine exists for this novel coronavirus, but research results about treatments are emerging.

The University of Minnesota has completed two comparative trials with hydroxychloroquine, a malaria drug that President Donald Trump says he is taking and has championed as a therapy. Published results could come out in the next week or two. On Monday, the World Health Organization halted trials of the drug, citing safety concerns.

The U’s Dr. Susan Kline was a lead author of a study published Friday in the New England Journal of Medicine on remdesivir, a drug that regulates the immune system’s response to infection. Recovery times for hospitalized patients with COVID-19 were around 11 days for patients receiving the drug, compared with 15 days for those taking nonmedicating placebo pills.

The death rate for patients on the drug appeared lower as well, but the effect was too small to be statistically significant, Kline said. Faster recovery is an important indicator, though, especially in the absence of proof of other treatments working.

“These are seriously ill people when they’re first admitted to a hospital,” she said. “From a clinician perspective, that is significant if you get someone’s clinical status improved to the point they can go home four days sooner.”

The federal government is regulating distribution of the drug for now for COVID-19 treatment, and has sent 4,946 vials to Minnesota — enough to treat 449 to 824 people depending on dosage levels.

Due to limited quantities, the state issued ethical guidance for prioritizing remdesivir for patients with certain levels of respiratory illness and likelihoods of survival.