Heh... I don't run it and if you're careful enough you don't need it.
Which means, don't install software from market or any other place if it doesn't have a few positive reviews from users.
Anyway, read the permissions upon installation and be cautious when an app requests permissions it really doesn't need.
Besides, Android "viruses" up until now were only malware/spyware so nothing to be really afraid of (except your valuable personal data

).