Editor's note: This story will be updated as the news evolves.

In announcing Michigan's first two cases of novel coronavirus late Tuesday, Gov. Gretchen Whitmer also declared a state of emergency, saying she will harness all of the government's resources to slow the spread of the virus.

"We're Michiganders. We're tough," Whitmer said. "We know how to take care of each other. We will get through this, but for now, please make sure your family and friends are taking every preventative measure available to keep yourselves safe. Talk to your friends, and your family and your co-workers and encourage them to make smart choices. We in state government will continue our work to take every necessary precaution to keep Michiganders safe."

The two people who have the virus — a man and a woman — are both middle age and both are hospitalized, said Dr. Joneigh Khaldun, chief medical executive and chief deputy director for health at the Michigan Department of Health and Human Services.

The woman is from Oakland County and traveled internationally. The man is a Wayne County resident with a history of domestic travel.

Both tests were processed in the state laboratories in Lansing.

"While these tests still have to be confirmed by the CDC (U.S. Centers for Disease Control and Prevention), we are proceeding with the public health investigation and response as if these are positive cases," Khaldun said.

"These are the first known cases of COVID-19 here in the state of Michigan. It is very likely that we will see more cases, and that there will be community spread. We need everyone to do their part to prevent the spread of disease as much as possible."

As of late Tuesday, the MDHHS reported that 77 people in the state have been tested so far for COVID-19, the disease caused by novel coronavirus. Of them, 57 have come back negative for the disease. Two were positive, and results from 18 tests are pending.

COVID-19 is a public health threat because it’s spreading so quickly around the world. Initial studies suggest it is more deadly than influenza and other common viruses.

Globally, 3.4% of people with COVID-19 have died, said the World Health Organization’s Director-General Tedros Adhanom Ghebreyesus at a March 3 news briefing. That compares to far fewer than 1% who die from the flu.

In addition to the higher fatality rate, there is no treatment or vaccine available yet for COVID-19. Comparatively, people can get the flu vaccine, and if they are infected with influenza, they can be prescribed an anti-viral medication to limit its severity.

While most people who contract COVID-19 have mild symptoms, 1 in 6 people who have the virus develop serious illness, and have difficulty breathing, according to the CDC. Those most at risk are older people and those with chronic health conditions such as diabetes, heart disease, suppressed immune systems and lung conditions.

How to protect yourself

Health officials recommend all Americans take these steps to prevent the spread of COVID-19 and other infectious diseases:

Wash your hands or using an alcohol-based hand sanitizer when soap and water isn't available

Avoid close contact with anyone who is coughing or sneezing.

Avoid touching your eyes, nose and mouth with unwashed hands.

Cover your mouth and nose with your arm or a tissue when you cough or sneeze.

Stay home if you are sick.

Clean and disinfect frequently touched objects and surfaces

Seniors and people with underlying health conditions such as lung disease, diabetes, heart disease or a weakened immune system are at highest risk for COVID-19 complications.

More:What everyone needs to know about traveling amid the coronavirus outbreak

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More:Seniors, sick are most vulnerable in coronavirus outbreak. Here's how to keep them safe.

In addition to following general recommendations, they also should avoid crowds, such as at sporting events, rallies, concerts and large community gatherings where there could be people who are carrying the virus.

People who are most vulnerable for having serious complications from COVID-19 also should consider checking their supply of medications to ensure they'd have enough in the event they are sickened by the virus, the CDC advised.

Contact Kristen Jordan Shamus: 313-222-5997 or kshamus@freepress.com. Follow her on Twitter @kristenshamus.