You never know where viruses are coming from these days... may not be the kids. I found something on my computer not long ago that fooled and re-programmed all of my anti-virus and anti-malware software... (it appeared like it was working when in fact it had been disabled) AND stole my e-mail username and password with a keylogger. I figured out I had a virus when I found several messages in my e-mail outbox that I had not written. CREEPY!!
I'm very careful with my machines because I keep a lot of valuable projects on them, and it seems like we can't always stay ahead of the game. I'm using Kaspersky anti-virus now, it was one of the few anti-virus programs that was "immune" to whatever hooligan programmer was after me.