Despite the success of vaccines in preventing millions of deaths and serious illnesses each year, many mysteries remain about how they interact with the immune system to produce immunity. Similarly, an understanding of how the immune system responds to infection is limited.
As a result, important questions persist. For example, why are older adults less likely to develop protective immunity after vaccination? Why are some individuals susceptible to a particular infectious disease and others are less susceptible?
Kuehn BM. Scientists Turn to Immune “Fingerprints” to Understand Vaccines, Infections. JAMA. 2010;304(22):2470. doi:10.1001/jama.2010.1765