Accidents happen even to the big manufacturers. If not, you have to check them yourself. Ask your manufacturer to check that next time you buy software. Beware of friends bearing floppies. You can't get a virus by looking at a text file or by reading a message on a BBS or other on-line service.
Viruses only come from executing software.
If the computer doesn't execute the program you can't get the virus attached to that program. So browse through that text file with software you've already verified as virus-free. Read your news. Chat on your favorite forum. Download your favorite text file, but don't download programs unless you're sure the BBS or on-line service regularly checks its disks and its uploads for viruses and other attacking software.