This class describes the basic immune mechanisms by which humans respond to pathogens (disease) including antibody responses and T cell responses. Some of these responses are desired because they are protective but some are not. Protective immune responses are the desired outcomes of vaccines, which can be achieved by careful vaccine design. These discussions will form a review of the desired characteristics of modern effective vaccines that increase targeted immunity. Emphasis will be given to increased safety of modern vaccines with a short review of published adverse issues. Also discussed are the risks and benefits of the traditional whole virus vaccine compared to a more targeted vaccine.