It wasn't failed isolation procedures like the title implies. He likely infected people before he was quarantined. We also don't even know that he was patient zero--he was just the first one diagnosed.
given his recent travel records and the genetic testing that linked his particular strain to subsequent patients, it's highly likely he was patient zero
He flew from Wuhan to Seattle. Presumably there were many other people on that flight. How likely is it that another passenger, who was asymptomatic or just didn't seek medical care, was the real patient zero?
