While your admonitions are well intentioned, I suspect they will be ignored by most in teh business settings above all. Unfortunate, but that seems to be the business ethic right now. As sick time has become more and more scarce, I can fully understand tough don't accept, that some people feel obliogated to come to work when sick. 

When sick I try to avoid going out in public, but until doctors will come to me again, as in days past, and milk, bread, meat, veges and fruit are brought to thehome  door; as a widower I sometimes have no choice but to venture out. 

As to your church: I sure know that mine, from the pulpit and the bulletin:

  1) encourages the sick to stay home

  2) recommends that you not shake hands if you don't feel well

  3) tells us not to shake hands, etc. if the other person is not willing, uncomfortable or is hesitant

  4) requires the commnion ministers to use hand sanitizer before distributing communion;      which is kept next to the altar for convenienc.

  5) tells us not to receive the Cup if we can not feeling well

maybe your could do the same.  It would certainly help.