Humanitarian Health Action

LANDSLIDES - Technical Hazard Sheet - Natural Disaster Profiles

The Hazard

Landslides are more widespread than any other geological event. They are defined as downslope transport of soil and rock resulting from natural phenomena or man made actions. There can be different types of movements: falls, slides, topples, lateral spread, and flows.

Landslides can be secondary effects of heavy storms, volcanic eruptions and earthquakes.

Factors of Vulnerability

Man made factors:

  • Intense deforestation, soil erosion;
  • Construction of human settlement in landslide prone areas;
  • Roads or communication lines in mountain areas;
  • Building with weak foundations;
  • Buried pipelines;
  • Lack of understanding of landslide hazards, lack of warning system.

Main Causes of Morbidity and Mortality

Direct Impact

Landslides cause high mortality and few injuries: trauma and suffocation by entrapment are common.

Short and long term mental health effects are observed.

Indirect impact

The impact on lifeline systems (water system, hospital, health centre, energy and lines of communication) present in the path of the landslide, is massive. They can be severely damaged or destroyed.

Indirect effect can include loss of property value, livestock and crops, increasing the vulnerability of the population, reducing their coping and caring capacities.

Foreseeable needs

Pending an assessment, needs can be anticipated such as: search and rescue, mass casualty management, emergency shelter for homeless.

Don't Forget

Landslides cause high mortality. Catastrophic debris slides or mudflows have killed many thousands by burying villages and hillside houses, by sweeping vehicles off the road into ravines.

Persons trapped in collapsed buildings must be rescued in the first 24-48 hours after the event in order to survive. This has evident implications for the type of assistance needed. Camp/field hospitals and rescue teams usually arrive too late to have a life-saving impact.

Frequency and occurrence of landslide can be estimated and areas at risk identified based on information on geology, climate, vegetation, hydrology.

Mitigation measures range from community education to monitoring, warning and evacuation systems.

Inappropriate Actions

Household medicines or prescriptions: Do not send them! These items are sometimes medically and legally inappropriate. Consult first WHO's guideline on essential drugs, and the local authority of the beneficiary country.

Medical or paramedical personnel or teams: Do not send them! They would arrive too late. Local and neighbouring health services are best placed to handle emergency medical care to disaster victims.

Unilateral decision on resource allocation: Do not take it without evidence of needs.

For further information please contact: WHO Health Action in Crises

Environmental Emergencies Mr J Hueb +(41 22) 791 3553 or

Injuries and Violence Prevention Dr E Krug +(41 22) 791 3535 or

Organization of Health Service Delivery Mr O Adams +(41 22) 791 2889 or

Mental Health Dr S Saxena +(41 22) 791 3625 or

For further reading:

An Overview of Disaster Management, 2nd ed. Geneva, United Nations Development Programme, Disaster Management Training Programme, 1992.

Coping with Natural Disasters: The Role of Local Health Personnel and the Community. Geneva, World Health Organization, 1989.

Do’s and Don’ts After Natural Disasters. Washington, Pan American Health Organization Press Release, 1998.

Emergency Health Management after Natural Disaster. Washington, Pan American Health Organization Scientific Publication 407, 1981.

Natural Disasters: Protecting the Public’s Health. Washington, Pan American Health Organization Scientific Publication 575, 2000.

Noji E. Public Health Consequences of Disasters. New York, Oxford University Press, 1997.Noji E. Public Health Consequences of Disasters. New York, Oxford University Press, 1997.