OT: Strange behavior from selfsending mail viruses?

[Anders Andersson, IT]

Hi
Either Im totally wrong or just missed this information if its been
discussed before.
Ive had my primary MX server down for almost 2 weeks and I noticed that the
viruses coming in has gone down with at least 80%. The only reason I can see
is that selfsending viruses only try to deliver their contaminated mail to
the primary MX record and not the second MX.
Has anybody seen this as well or have I just been lucky the last 2 weeks

/Anders