Michigan Gov. Gretchen Whitmer warned Tuesday that a Detroit-area hospital system was "almost at capacity" treating people with the coronavirus, as the state's stay-at-home order kicked in to reduce the spread.

The governor, speaking about her measure with WDET-FM, pointed to Beaumont Health, which has eight hospitals in Wayne and Oakland counties and describes itself as Michigan's largest health care system.

"Let's be very clear: Beaumont Health is almost at capacity right now. We have not seen the worst of it yet," she said. "The numbers are going to continue to climb."

The Associated Press left messages with the governor's office and Beaumont seeking additional information and clarification.

Nearly 1,800 people have tested positive in Michigan for the coronavirus. Roughly 73 per cent of cases — about 1,300 — are in Wayne County, which is home to Detroit, and adjacent Oakland County. COVID-19 deaths have climbed by nine, to at least 24.

Oakland University, which sent students home, has offered its dorms, arena and parking lots to Beaumont for makeshift medical purposes. The president, Ora Hirsch Pescovitz, who is a physician, predicted local health care providers will become swamped. She said residence halls could be used to isolate people.

Oakland County executive Dave Coulter, whose county had 100 confirmed virus patients in the hospital, said Beaumont was converting some operating and surgical rooms to intensive care units to boost capacity.

"We're planning for the day when they are no longer able to increase their capacity, and then we're going to be prepared to help them," he said.

I’ve always said our state is an extraordinary place to live because of those who call it home, and you’re proving that to be true.<br><br>Michiganders are tough.<br>Michiganders care about their neighbors.<br>Michiganders step up and lead.<br><br>We’re going to get through this together. <a href="https://t.co/MIOzjElJLS">pic.twitter.com/MIOzjElJLS</a> —@GovWhitmer

Coulter said the county was working with the National Guard to potentially set up a mobile hospital and talking to hotels, conference centres and colleges about housing infected people. Patients could include those who may need to be isolated and quarantined but not hospitalized.

"We're going to prepare for a worst-case scenario because that could happen sooner rather than later," he said.

Whitmer has barred employers from requiring workers to leave their homes unless necessary to protect life or conduct minimum basic operations during the pandemic. There are exceptions, including grocery stores, banks, gas stations and restaurants offering carry-out or food for delivery.

Also Tuesday, the state health and human services director Robert Gordon ordered labs to prioritize sampling and testing for COVID-19 and to quickly report results and deaths. Hospitals were told to timely report their bed and lab testing capacity, personal protective equipment inventory, and the number of ventilated patients and ventilators.

This disease can't spread person to person if we're not out there. - Michigan Governor Gretchen Whitmer

In Petoskey, in northern Michigan, Emmet County Sheriff Pete Wallin said deputies will investigate complaints about people violating Whitmer's command but that "there will not be any arrests." Other police agencies have offered similar messages.

For most people, the new coronavirus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. The majority of people recover.

A Detroit police dispatcher who caught the virus when he traveled outside Michigan died Monday. Detroit Mayor Mike Duggan said the 38-year-old man was not feeling well when he returned to work on March 16 after a trip.

"This disease can't spread person to person if we're not out there," Whitmer said Monday in pleading with people to stay home.

Separately, 282 Detroit officers were off work awaiting test results or self-quarantining, although 152 were expected to return by the end of the week, Duggan said. The department has about 2,200 officers, according to its website.

Meijer, which has stores in Michigan, Wisconsin, Ohio, Indiana, Illinois and Kentucky, is urging shoppers to keep reusable bags at home and instead use store bags to keep people safe.

The pandemic has led to acts of generosity. A Lansing-area man twice dropped off $1,000 to be shared by employees at Darrell's Market & Hardware near Mason.

"I think he just wanted to support people that are still working. He's pretty special," owner Jamie Robinson told the Lansing State Journal.