MORENO VALLEY (CBSLA) — The Americans who were evacuated from the epicenter of the novel coronavirus and taken to March Air Reserve Base In Moreno Valley will now have to be quarantined for two weeks, the Centers for Disease Control said Friday.

The evacuees from Wuhan, China arrived in Moreno Valley Wednesday after multiple health screenings and were originally going to be released after only three days in isolation.

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But now that health officials believe it can take up to 14 days for someone to develop the symptoms of novel coronavirus, all 195 people have to remain in federal quarantine for two weeks. The move is the first time in 50 years that the CDC has issued such a quarantine order.

“While we recognize this is an unprecedented action, we are facing an unprecedented public health threat,” said Dr. Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases.

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The novel coronavirus was declared a global public-health emergency by the World Health Organization on Thursday. On Friday, the U.S. State Department issued a “Do Not Travel” warning – its highest level – for China.

The outbreak has killed more than 200 people and sickened nearly 10,000 more in 18 countries.

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