Innoculation 101

Virus actions appear to comprise as much as 50% of all SMTP traffic - indicating high rate for various bugs identified/quarenteen'd at major mail providers:

Texas A&M Statistics:
http://www.tamu.edu/network-services/smtp-relay/configs/stats/consolidated.html

Barracuda Central (commercial anti-spam email system):
http://www.barracudacentral.org/data/virus

Web Lab - European Consulting:
http://www.wecltd.eu/viruses/index.en.php