Abstract: The iterative detection and treatment of viruses using virus detection objects and virus treatment objects is disclosed. Pursuant to a request for a virus scan, a virus detection object is produced by a server and is transmitted to a client for execution. The client receives and executes the virus detection object, and the results are transmitted to the server. The server uses the results to produce an additional virus detection object which is also transmitted to the client and executed so that the results can be transmitted to the server. The iterative production and execution of virus detection objects is continued until a determination is made as to whether the targeted file or data includes a virus. Upon a determination that a targeted file or data includes a virus, a vaccine specifically tailored to the conditions presented at the client and the type of virus detected is produced, preferably in the form of a virus treatment object.