investigation or contact tracing, if necessary. In addition, Taiwan CDC staff determined the need and gave instructions for self-monitoring or home quarantine, depending on current policies and any special situations.

Case Detection
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The enhanced border quarantine procedures led to early detection of a suspected case of COVID-19. On January 20, a 55-year-old woman reported fever, cough, and shortness of breath at her airport health screening upon arrival from Wuhan. She was transported directly to the hospital, averting local exposure. She reported that she wore a mask and remained in her seat for the duration of the flight. The crew and other passengers, who had no prolonged direct interaction with her, passed the health evaluation at the airport and were directed to complete a 14-day self-monitoring regimen at home. During self-monitoring,passengers and crew were required to record their temperature twice daily, stay home, or wear a mask if they had to go out; as an extra measure, they had to respond to daily telephone checks by infectious disease staff.

On January 21, the passenger with symptoms was confirmed to have COVID-19, the first known imported case in Taiwan. The same day, the United States announced its first case in a 35-year-old man who had returned from Wuhan on January 15 and was later admitted to a hospital in Washington State on January 19 ([@R4],[@R5]).

With confirmed cases reaching 1,400 globally, including cases in Europe ([@R6]), Taiwan's disease investigation teams worked through the week-long Lunar New Year holiday. Beginning on January 24, Lunar New Year's Eve, all passengers traveling from China,