This book presents the application of pulsed electrical discharges in water and water dispersions of metal nanoparticles in medicine (surgery, dentistry, and oncology), biology and ecology. The intensive electrical and shock waves represent a novel technique to destroy viruses and this way to prepare anti-virus vaccines. The method of pulsed electrical discharges in water allows to decontaminate water from almost all known bacteria and spores of fungi being present in human beings. The nanoparticles used are not genotoxic and mutagenic. This book is useful for researchers and graduate students.