Personalizing Vaccination for Infectious Disease in the 21st Century

Current approaches to vaccination have several underlying assumptions, namely that following immunization most individuals are at similar risk of the disease considered; will react immunologically in the same way (with protective antibodies and/or cell-mediated reactivity) with equivalent and minimal side effects; and that vaccination dosing and frequency of administration does not vary in the population at large. As a result, a widespread delivery of vaccines has been achieved for a number of infectious diseases, with effective control for many of those. It is clear that a weakness of this approach, made manifest with our increasing knowledge of the genomic and proteomic approach to medicine which has come to the fore in the last decade or so, is that it discounts the growing evidence for individual variability in risk; in immune responsiveness; and in response to different doses of vaccine. While this evidence grew from a focus on tailoring individual approaches to cancer therapy, and has revolutionized our thoughts on drug therapy, drug pharmacogenomics and toxicity and the importance of understanding at the individual, not population level, unique responses to treatment, application of the same approach to vaccines for infectious disease has not had a similar attention. Indeed, not only does consideration of individual specific factors challenge a traditional public-health level paradigm of infectious disease vaccinology, and confront newer approaches based on genetically encoded individuality in response to pathogen challenge, but the cost-benefit of such an approach has, to the author’s knowledge, not been considered at all. The review below will consider these issues in greater detail, with a final focus on how this might dictate our global responses to emerging infections.