In a distributed network having a number of server computers and associated client devices, method of creating an anti-computer virus agent is described. As a method, the inoculation is carried out by parsing a selected computer virus into a detection module that identifies a selected one of the client devices as a target client device, an infection module that causes the virus to infect those target client devices not infected by the selected virus, and a viral code payload module that infects the targeted client device modifying the infection module to infect those computers already infected by the selected virus; and incorporating inoculation viral code in the payload module that acts to prevent further infection by the selected virus.