Dr.Web is nothing but the Parallels antivirus software within the control panel itself. Dr.Web can be disabled by the following ways.
Edit the file /etc/drweb/drweb_handler.conf as shown below to stop Parallels Premium Antivirus from sending notification messages:
[VirusNotifications]
SenderNotify = no
AdminNotify = no
RcptsNotify = no
Edit the file /etc/drweb/drweb32.ini
CronSummary no
Restart Dr. Web :
/etc/init.d/drwebd restart