With most pathogenic and etiologic agents of deadly diseases acquiring resistance to currently used drugs, the development and formulation of vaccines against predominant infectious diseases has taken centre stage. Our review aims, based on our understanding and knowledge of the process of pathogenesis and its intricacies in particular, to throw light on the aspects of vaccine development. The basic platform for formulating a vaccine involves deciphering the kinds of immune responses to the various antigenic factors of the pathogen. Other particulars, such as immunological memory (primarily mediated by antibodies post-natally), immunopathology of infections, and the selective balance of Th1-Th2 responses are also considered grounding factors for the construction of "immunity eliciting vaccines". The nature of vaccines (either humoral antibody immunity inducing or cell-mediated immunity inducing) depends on the location (extracellular or intracellular) and the expression of the antigens selected for incorporation. To maintain the synergism between the kind of immunity conferred by the vaccines and the cellular location of the included antigens, new findings are gathered about the virulence factors such as toxins, adhesins, invasins (mostly enzymes), anti-apoptotic factors, anti-phagocytic factors, and many more molecules that aid in pathogenesis and invasiveness. The concept of an all-in-one vaccine versus a one-in-one vaccine is also discussed. Bioinformatics tools and algorithms like BLAST and FASTA are nowadays being adopted as a means to identify and detect common target antigens against Gram negative bacterial pathogens. One of the more recently identified and well-studied gram negative bacterial candidates has been Choline phosphorylase. Homology searches have thus facilitated the discovery of potential candidates for an all-in-one vaccine.

Pharmacogenomics is the study of genetic differences responsible for the variability in drug response among individual patients. Emerging from this new science is the development of diagnostic tools crucial for decreasing drug side effects and optimizing treatment strategies. However, both application and progress have been troublesome in guiding treatment of genetically-linked diseases such as cancer and diabetes. The complexity of multiple gene interactions requires a collaborative effort to understand the genetic bases of variable drug response. Societal quandaries also burden research. The novel genomic information to be used in tackling disease may be viewed as discriminatory factors involving winners and losers. Concerns of privacy and cost as well as changes to today's medical education and practice will unsettle the American healthcare system. This article reviews the feasibility and potential of applying the latest advancements in genomics to medicine and drug development.