This book introduces readers to the history and discovery of viruses and bacteria. It provides an accessible overview of how several major pandemics have influenced the society and how vaccines and antibiotics were developed. Dive into the fascinating illustrated stories behind 17 common infectious diseases, and learn about the pathogen characteristics, main symptoms, transmission routes, as well as prevention and control strategies. By featuring the difficulties in the struggle against infectious diseases, the contents highlight the scientific spirits and the stories of scientists. Human beings' faith in seeking out the unknown is highly praised, and it is hoped that this book will stimulate people's belief in scientific ideas and methods.