When New York City announced on Tuesday that it would soon require people to show proof of at least one coronavirus vaccine shot to enter businesses, Mayor Bill de Blasio said the system was “simple — just show it and you’re in.”Less simple was the privacy debate that the city reignited.Vaccine passports, which show proof of vaccination, often in electronic form such as an app, are the bedrock of Mr. de Blasio’s plan. For months, these records — also known as health passes or digital health certificates — have been under discussion around the world as a tool to …
