Symentec has been very busy lately, with updates very frequently.
A couple of weeks ago, on the weekly complete run through, they found and quarantined four items with Trojan viruses. The following week they were removed.

I think I may have caught this new Dluca virus from a newspaper. I downloaded an editorial cartoon, and an icon for it popped up on my desktop, without any help from me. If nothing is caught at the next complete scan, I will ask Symentec about it and complain to the paper (Calgary Herald).