In light of a recent increase in COVID-19 “Delta” cases and despite an uptick in vaccinations, a number of major events and concerts are being canceled across the United States. Former Fleetwood Mac singer Stevie Nicks, for example, announced on Aug. 11 that she’s canceling all her remaining performances in the United States, including dates in California and Colorado next month, as well as performances scheduled for New Orleans and Austin, Texas, later this year. “Because singing and performing have been my whole life, my primary goal is to keep healthy so I can continue singing for the next decade or longer,” Nicks wrote on social media, adding that she wants to perform again next year. “I’m devastated and I know the fans are disappointed, but we will look towards a brighter 2022.” Jason Isbell and the 400 Unit’s record label said the band’s Aug. 11 show in Houston, Texas, was canceled …