CONSISTENT PATTERNS IN SECONDARY HEALTH EFFECTS OF DISASTERS

Most disasters produce a consistent pattern of death and injury. Primary causes are directly attributable to the event itself and thus vary by event type, e.g., drowning in tropical storms and floods, direct trauma in earthquakes and tornados. Secondary causes vary less by event type as they are driven by common effects: loss of electrical power and shelter, transportation disruption, loss of healthcare access, attempted repair/restoration, and other disruption of daily routine. Primary and particularly secondary causes may be difficult to attribute, typically leading to undercounting. Secondary causes of death, illness, and injury can be divided into four broad categories: pre-existing medical conditions, environmental degradation or magnified exposure, secondary trauma, and psychological effects.

Pre-existing medical conditions include common non-communicable diseases that are typically medication-controlled (e.g., cardiorespiratory ailments, diabetes, psychological disorders), rely on recurring procedures (e.g., hemodialysis for end-stage renal disease), or a combination; some conditions require regular oxygen administration, powered life-support equipment, or other adjuncts. The link among all is the dependence on maintenance care, the disruption of which turns a chronic, relatively stable condition into an acute one at the worst possible time. Environmental causes include unmediated exposure to ambient environment, degraded air and water quality (including otherwise-controlled infectious diseases), and introduced toxicants (most commonly carbon monoxide). Secondary trauma includes motor-vehicle collisions, electrocution, and other injuries, particularly those related to repair and short-term recovery. Psychological causes include response to the primary event beyond effects of pre-existing conditions: disruption to lifelines and routine and extended effects (e.g., prolonged outages, seismic aftershocks, personal loss).

Most secondary health effects of disasters are predictable and can be prevented or at least lessened by the combination of awareness and deliberate action by governments, institutions, support services, and individuals. In actual practice, secondary effects recur in most events and see limited preventive measures.