CALGARY—A world-famous annual rodeo that survived the Great Depression, two world wars, and a devastating flood seven years ago was felled by a microscopic virus this year and will have a different look if it’s allowed to go forward in 2021. Calgary Stampede president Dana Peers says planning is underway, with fingers crossed, to stage the celebration of cowboy life, which brings in a million visitors each year and gives the local economy a $282-million boost. “Who would have thought it would be a pandemic that would really take us to a whole new level of challenge?” Peers said in an interview. The Stampede first started on an annual basis in 1923. It had been held every year since, including in 2013 when Calgary and other communities in southern Alberta were devastated by flooding. The grounds were under water, but frantic efforts enabled the 10-day rodeo, fair, and midway to …