Just like we have memories from past experiences, our immune system also remembers previous pathogens that it encountered. We are interested in studying the effect of immune memory (history) on responses to vaccines and infections. Our research has uncovered that we can identify individuals with poor immune histories that are at an increased risk of viral infections. We are developing experimental tools to profile immune history, with particular interest in antibody responses. We are also developing computational tools to predict based on immunological history which individuals are likely to be protected from infections.