DROUGHT - Technical Hazard Sheet - Natural Disaster Profiles
Drought is a prolonged dry period in natural climate cycle. It is a slow-onset phenomenon caused by rainfall deficit combined with other predisposing factors.
Drought often results in mass displacements of population.
Drought leads to water and food shortages and is likely to have a long-term environmental, economic and health impact on the population.
Droughts are often predictable: periods of unusual dryness are normal in all weather systems. Advance warning is possible.
Factors affecting vulnerability
Factors influencing the impact of drought are:
- Demographic pressure on the environment;
- Food insecurity;
- Economic systems strictly dependent on agriculture;
- Poor infrastructure e.g. irrigation and water supply and sanitation systems;
- Poor health status of the population before the disaster;
- Time of the year, with the most critical period being before the harvest;
- Absence of warning systems;
- Population displacement;
- Other concurrent situations: economic crisis, political instability, armed conflict.
Main causes of mortality and morbidity
Reduced food intake and lack of varied diet leading to:
- Protein-energy malnutrition;
- Micronutrient deficiency: Vitamin A deficiency increases the risk of death from measles; severe iron-deficiency anaemia increases the risk of child and maternal mortality. Outbreaks of scurvy due to vitamin C deficiency, of beriberi due to thiamine deficiency, or of pellagra due to niacin deficiency can also occur.
Communicable diseases. Lack of water supply and sanitation services, malnutrition, displacement and higher vulnerability of the population all increase the risk of infectious diseases such as cholera, typhoid fever, diarrhoea, acute respiratory infections and measles.
Migration, loss of buying power and erosion of coping and caring capacities limit people's access to health services and can contribute to an overall increase in morbidity and mortality.
Pending assessment, anticipated needs would be: Food aid, water supplies, water quality control, excreta disposal facilities, surveillance and control of communicable diseases, assessment and surveillance of nutritional status of the affected population (nutritional surveys), limitation and/or management of population displacement.
Food aid programmes:
- General food distribution. Pending a detailed assessment of food aid requirements, the initial basic ration should provide at least 2100 Kcal per person per day. The food ration should be as simple as possible: a basic staple (e.g. rice, corn, wheat flour, Corn Soya Blend), a concentrated source of energy, (oil or another fat) and a concentrated source of protein (e.g. pulses). It should also be culturally acceptable.
- Supplementary feeding is intended to correct moderate malnutrition and prevent deterioration of nutritional status among those most at-risk, namely young children pregnant women and lactating women. It can be distributed through on-site feeding (or wet rations) or as take-home dry rations.
- Therapeutic (intensive) feeding is used as treatment for severely malnourished individuals e.g. children whose weight-for-height is below -3SD (standard deviation) or less than 70% of the median NCHS/WHO references values (termed "severely wasted") or who have symmetrical oedema involving at least the feet.
Help people not move from their home. Badly planned food aid can amplify migration. Efforts must be made to avoid creating displaced-person camps.
Food aid is a complex issue:
- It affects the economic, social and political systems.
- Logistic, political and physical constraints have to be taken into account when planning food aid.
Relief food distribution are often necessary in the early stage of an emergency. However, the objective of all assistance should be to help the affected population to achieve self reliance from the earliest possible moment. Thus, food aid must be considered as a palliative and temporary measure.
Regional and local purchases should be pursued whenever feasible.
Activities should be integrated. Rehabilitated children will slip back into their previous malnourished conditions unless there is a strategy broader than food distribution which encompasses the maintenance of family food security and caring capacity.
The health sector can contribute with data and guidelines to intersectoral policies e.g. food security, population. Then it can contribute to early warning systems, dissemination of information, decisions, intersectoral interventions and coordination .
The risk and severity of communicable diseases outbreak are increased. A surveillance and response system needs to be in place.
All disasters cause psychosocial stress in the affected population. Mental health needs are to be considered part of the health care during all phases of assistance.
Health services can also be directly affected. Health posts may run out of water; community health workers will be affected by shortages and economic distress and may be forced to leave their villages.
Do not send household foods or food items unless explicitly requested. Donate money to purchase large amount of food locally.
Do not send "baby foods". Encourage breast feeding. Consult WHO's recommendations for " Ensuring optimal feeding of infants and young children during emergencies".
Do not send household medicines or prescriptions. These items can be medically and legally inappropriate. Consult WHO's guidelines on essential drugs and the local authority of the beneficiary country first.
Do not take unilateral decisions on resource allocation without evidence of needs.
For further information please contact:
WHO Health Action in Crises firstname.lastname@example.org
Environmental Emergencies Mr J Hueb +(41 22) 791 3553 or Huebj@who.int
Nutrition in Emergencies Ms Z Weise Prinzo +(41 22) 791 4440 or Weiseprinzoz@who.int
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.
Drought and the Health Sector. Panafrican Training Centre/World Health Organization, 1998 (unpublished document available from Division of Emergency and Humanitarian Action, World Health Organization, 1211 Geneva 27, Switzerland).
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.
The Management of Nutrition in Major Emergencies. Geneva, World Health Organization, 2000.