no, the virus didn't somehow get more contagious in march, it had just spread farther/deeper. the same measures would have reduced risk equally in either case.

no, the virus didn't somehow get more contagious in march, it had just spread farther/deeper. the same measures would have reduced risk equally in either case. only the likelihood of need (that those measures would have non-trivially helped prevent spread) would have gone up on a per-interaction basis.