A "disease vector" is a website or URL known to distribute Internet security risks including spyware/grayware, password-cracking applications, key-stroke trackers, and virus/malware kit downloads.

Another category of disease vectors are sites made to look legitimate, but below the surface the hacker directs all the "back-end" functionality such as links and data posts to his or her own locations.

Trend Micro quickly adds confirmed malicious sites to the phish and spyware pattern file so you can prevent LAN clients from downloading the virus/malware, or from being duped by the look-alike sites.