This book paves the way for helping children in understanding the principles of virus by the way of telling the secrets of illness through vivid, personified and graphic illustrations. Seven common illnesses in children will be introduced in this book for acquiring prevention knowledge and enhancing self-protection awareness. This book motivates the reading interest of children in vivid graphs from the perspective of children firstly and children will have an initial understanding in illness step by step. Every book is attached to the words from pediatrician to parents and the words include straight precise prevention strategies, which are helpful in deepening the understanding of parents. Therefore, parents and children can work together to defend the health of children.