Are these virus warnings for some particular file that is being accessed or downloaded, or for the site in general?
Perhaps you need to contact Norton et al to get an explanation as to why they are flagging that file/site, and if it is a "false positive", find out if there is some work-around you can use to avoid it. (Perhaps if it's an image file, simply converting it to a different format?)
Anyway, to answer your original question, I can see no way to determine if a user is running one of those programs, other than something like an ActiveX program or similar, which has a couple problems: (1) the user has to agree to allow such a program to run in the first place, and (2) it's probably the sort of thing those security programs would (correctly) flag as a security risk.