What Mattered This Week: January 27-31, 2020

The U.S. joined the World Health Organization on Friday in declaring a public health emergency over the outbreak of a new coronavirus originating in Wuhan, China. The virus has so far sickened nearly 9,800 people worldwide. Plus, the U.K. formally left the European Union, and the Senate voted to reject a Democrat-led effort to call witnesses in the impeachment trial of President Trump. Read up on these and more of the week's top headlines.

What Mattered This Week: January 27-31, 2020

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