Public Health Infectious Disease (print version) and Learning Public Health Infectious Disease (Apps version) are meant to function as a handy manual in infectious disease for undergraduate and postgraduate students in public health, nursing as well as medical students going through public health training. Currently despite the abundance of textbooks in infection, these are often bio-medically oriented with an emphasis on the biological mechanisms and clinical management. Tailored learning materials with a public health perspective are in short supply. The shortcoming is compounded by the relative lack of locally relevant resource materials which could be used for teaching purpose. This set of publications is designed to fill these gaps. Today, the number and diversity of people specialising in public health are continuing to rise. Hopefully, the book and the Apps would also serve as references for health and social science professionals working in the public health field in Hong Kong and other cities in the region.