“Something extremely bogus is going on. Was tested for covid four times today. Two tests came back negative, two came back positive,” Musk said on Twitter. “Same machine, same test, same nurse. Rapid antigen test from BD.”

https://thehill.com/blogs/in-the-know/in-the-know/525817-elon-musk-knocks-extremely-bogus-covid-19-test-after-taking