Rochester, Minnesota - COVID-19, which was first detected in Wuhan City in China, has now been identified in 37 countries, including the U.S.

U.S. cases of COVID-19 have been limited so far. The Centers for Disease Control and Prevention (CDC) has now confirmed the first possible U.S. case of "community spread," meaning the patient didn't travel anywhere known to have the virus and wasn't exposed to anyone known to be infected.

"We'll have to find out a bit more about where or how this person may have acquired the disease," says Dr. Nipunie Rajapakse, a Mayo Clinic infectious diseases specialist. "We do know that it can be spread from person to person and now we're seeing the virus appear in many different countries around the world. We do expect that it will start to circulate in the U.S. We're watching and waiting to see when this might happen, and cases like this may be some of the first clues to suggest that the virus has entered its way into the country."

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The CDC says that the potential public health threat posed by COVID-19 is high, both globally and across the U.S.

COVID-19 can cause various symptoms that may appear two to 14 days after exposure. The most common symptoms include fever, cough and shortness of breath. The severity of COVID-19 symptoms can range from mild to severe, including death. More than 80% of cases are mild.

The CDC and the World Health Organization are closely monitoring the evolving health situation and offer updated information, as available.