Clearly -- and often humorously -- written, PDQ Public Health defines public health and covers the basic concepts of public health policy, including its history, local to international structure, and role in protecting human health. Concise, yet comprehensive, PDQ Public Health educates the reader in the history and evolution of the concepts and practices of public health on local, national, and international scales. Key concepts, such as communicable diseases, vectors, hosts, and environments, are defined; and how they and other factors interact to influence public health issues is described. The statistical tools that are used to determine risk and describe the interactions contributing to community health are presented. The authors also address the impact of population mobility, economic factors, government (law), and ethics, on the practice of public health. This is all done in an engaging style that aids the reader's comprehension of this complex subject.