Its severity is often measured by the number of people affected by its geographical extent, or the disease or death of the pathogenic process which it originates.
- Public health problem 
- Problem health coordination
- Alarm care. Poor communication of risks to the population orgine social upheaval.
- 1858: Swill milk
- 1905: American meat scandal due to the publishing of Upton Sinclair's book "The Jungle".
Prevention and control
- Using the health warning systems. A health system responsive to the needs of the population is required to refine the instruments to ensure adequate preparation before their hatching.
- Transparency of the institutions public or private. The perception of crisis can escape the control of experts or health institutions, and be determined by stakeholders to provide solutions propagate or concerned. This requires a difficult balancing of the need to articulate clear answers and the little-founded fears.
- Adequate information policy. Irrationality arise when information is distorted, or hidden. Face a health crisis involves: respect for society, coordination of organizations and an institution with scientific weight to the people and to the media, who acted as spokesman in situations of public health risk, to get confidence citizens. The technical capacity of health professionals is more proven than the public officials, which suggests a greater share of the former and better training of the second.
- Evaluate the previous crisis or others experiences. Crises are challenges that must be learned from both the mistakes and successes, since they serve to bring about to the devices and improve the response to other crises. It is important to perform analysis of previous responses, audit risk and vulnerability, research and testing, and drills to prepare themselves against future crises.
- Having objectives: "first, to reduce the impact of illness and death, and second, to avoid social fracture".
- Preparing contingency plans. Preparation is key to the crisis because it allows a strong response, organized, and scientifically based. Action plans must meet the professional early enough and properly trained, and politicians must be consistent in their actions and coordinate all available resources. It is essential to invest in public health resources to prepare preventive measures and reducing health inequalities to minimize the impact of health crises, as they generally always the poorest suffer most.