This should really be in the Gen Dis forum but since most of you don't check there I'll leave it here in the interests of informing people.
The SirCam virus (dunno about this Isobar one) and a few other new virii and Trojans check the temporary internet folder of an infected user for email addresses and will propagate by sending itself to those email addresses, in addition to addresses it finds in the Outlook Address Book. So any site that that user has been to that is still stored in their cached net files will be at risk.
Click
here for more information on this.
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