Some of the emotional effects are direct responses to the trauma of disaster. Other effects are longer-term responses to the interpersonal, societal, and economic effects of the disaster. In any case, in the absence of treatment, up to fifty per cent or more of the victims of a disaster may develop lasting depression, pervasive anxiety, post-traumatic stress disorder, and other emotional disturbances. Even more than the physical effects of disasters, the emotional effects cause long-lasting suffering, disability, and loss of income. There is no single, universally applicable recipe for responding to disasters.
Disasters come in many forms.
Disasters may be relatively short lived, although devastating, or, as is the case with famine and war, may last for years. Perhaps the greatest source of variability, both in the effects of disaster and in the most appropriate responses, stem from differences between the countries and cultures in which a disaster occurs. There are two major components of this variability. First, the level and patterns of economic development varies from country to country. Wealthy countries face disasters with a wealth of human and material resources, a well-developed medical and mental health infrastructure, and efficient transportation and communication systems.