"I'm happy to have people celebrating summer, but I think that all of us should be conscious that this pandemic is not over," McGeer said in an interview. "It's likely that we, like many other countries in the world, may see more cases and more transmission of Delta, and that we will need to intervene ... to mitigate serious disease and death." McGeer said it is clear the Delta variant is on the move in British Columbia, Alberta and much of the United States, where the U.S. Centers for Disease Control and Prevention now say fully vaccinated Americans should go back to wearing masks in indoor public spaces in regions where the virus is spreading rapidly.