Dik LaPine has been a postman in Duluth, Minn., for 21 years and prides himself on rarely missing shifts. The 62-year-old carrier’s six-hour route has him stopping into many Duluth businesses and a smattering of homes every day.

On Monday, as concerns continued to rise about the spread of the new coronavirus, Mr. LaPine clocked in at about 7 a.m. to prepare his deliveries to banks, real-estate agencies, nail salons, bars and restaurants. The local shopping mall is also on his list.

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