Public Health and Disasters: Risk Assessment and Mitigation - Hardcoverby Lawanna Boone (Editor) Public health emergencies can be defined as events that adversely impact the public health system and or its protective infrastructure such as water, sanitation, shelter, food, fuel and health. Public health emergencies shift the focus of healthcare from individual patients to mass casualties. The objective of a public health emergency is to build and promote the capabilities of health systems, communities and individuals for