This book reviews the use of nano-based drug delivery systems and biomaterials to enhance the immune system against infectious diseases. It focusses on the inbuilt immunoreactive properties of nanomaterials and the advancement in its engineering to modulate the immune system either via immune-stimulation or immunosuppression. The book further discusses the use of nanoparticle-based vaccines to improve vaccine efficacy, immunization strategies, and targeted delivery to achieve desired immune responses at the cellular level against infectious diseases.  Perhaps, book focusses on nanoscale diagnostics that offer new approaches for sensitive health monitoring that are potable and can guide the use of nanoscale therapies. This book explores the potential of immunomodulatory nanotechnologies, focusing not only on their benefits, but also on biocompatibility, and toxicity concerns, while highlighting promising innovations in Interferon-based immune therapies and addressing key challenges in achieving safe, scalable nanotech products. The book would encompass broad topics to attract the diverse specialty of physicians, health professionals, students, faculty, and researchers of nanotechnology, nanomedicine, infectious diseases, public health, immunology, bacteriology, virology, pathology, biotechnology, toxicology, and biomedical technology.