IT people need to be given special status and permission to do unusual things such as remote support/management. Every situation will be unique, but in some situations I could see closing the office to everyone EXCEPT IT, or forbidding anyone else from interacting face to face with IT, or perhaps staggering their work hours to keep them from contact, and giving them all masks in case one of them is beginning to catch the flu. The critical period for any given location would probably be just a few weeks.