We all have one person, maybe more, in our list of friends, neighbors, family members or others, that seem to get infected no matter what we try to teach them about staying bug free. I know my cross to bear is my friend and neighbor who lives across the street from me. He gets infected, I scold him, clean his system and he gets infected again.
Sometimes cleaning a bug off of his system goes quickly. But sometimes it takes time. So what I have done is placed a free copy of SUPERAntiSpyware Portable Scanner on an old USB drive, and now just hand it to him.
FWIW – this scanner is not very fast. It fact it is kind of slow, IMHO. But it is a freebie, portable and could fit your needs if you have people around you that get quite a few infections.