This book systematically assesses the risk of 21 major infectious diseases threatening BRI countries. It consists of 14 chapters. Chapter 1 is an overview. Chapter 2 introduces the history of health cooperation between China and other BRI countries. Chapters 3-14 introduce the prevalence of major infectious diseases threatening BRI countries such as cholera, vaccine preventable diseases (polio, measles, meningitis, Japanese encephalitis, diphtheria, hepatitis A), tuberculosis, influenza, and insect-borne diseases (Dengue fever, Zika virus disease, yellow fever, Chikungunya, Rift Valley fever), plague, malaria, Ebola virus disease, MERS, schistosomiasis, COVID-19 and AIDS, and  risk factors, principles and cases of their prevention and control.                      It is a useful reference book in the research of infectious disease control and prevention, and provides historical experience and lessonslearned. It also provides decision support for international cooperation among BRI countries in the field of epidemic prevention and control in the future.