Can iPhone get a virus
It is very possible for an iPhone to get a virus. The iPhone virus exploits a memory corruption bug. This is in the way the iPhone handles text messages. You can get detailed information on http://www.pcworld.com/article/169405/iphone_virus_what_you_need_to_know.html.
It can, but it is hard to get one.
No. I've had the iPhone since it first came out. I've never had a virus.