WHO: How flooding affects health

Floods are the most common natural disaster in the WHO European Region, occurring in 50 of the 53 countries in the WHO European Region in the past decade. More frequent, extreme rainfall is projected; it may result in more floods, of greater intensity and various types. Flooding has extensive and significant effects on health, spanning the short and long terms and ranging from drowning and injuries to infectious diseases and mental-health problems.

Over the past 10 years, flooding killed 1000 people and affected more than 3.4 million in the Region. Two thirds of such deaths are from drowning, and the remainder from physical trauma, heart attacks, electrocution, carbon monoxide poisoning and fire.

Health effects observed during and after floods include injuries, infections, poisoning and greater mental-health problems. Outbreaks of infectious disease are rare. The longer-term health effects result from displacement, shortages of safe water, injuries, disruption of access to health services and delayed recovery.

The flooding of health facilities disrupts services, and results in loss of infrastructure (such as water supply and electrical power) and increased difficulty in providing routine care for patients with chronic diseases, at a time when admissions increase.

If no preventive measures are taken, European studies project that river flooding could affect 250 000–400 000 additional people per year in Europe by the 2080s, more than doubling the numbers for 1961–1990. Rises in sea level and storm surges, which cause coastal flooding, could affect millions more people.
Emergency preparedness for flooding

Adequate planning is vital to minimize the health effects of floods: using a wide, multisectoral, all-hazards approach to emergency preparedness in developing local plans that include public health and primary care.

Key aspects of this planning include:

• long term land-use planning, including building health facilities in appropriate areas (for example, avoiding flood plains);
• structural protection and flood-proofing of health care facilities;
• establishment of early warning systems and evacuation plans;
• identification of vulnerable or high-risk populations;
• information and communication strategies, particularly to reach the people most at risk and most vulnerable (such as those with chronic diseases, who require continuous treatment);
• measures to ensure water quality, sanitation and hygiene, and food safety during and after a flood;
• identification of health precautions during clean-up operations and protective measures against communicable diseases and chemical hazards;
• measurement and tracking of mental health and well-being; and
• robust surveillance during and after floods.

Study on the health effects of flooding

In 2009–2011, WHO/Europe and Public Health England, United Kingdom, conducted a project to investigate the health effects of flooding, and to find the best ways to protect health in the WHO European Region. They collected information through a questionnaire sent to Member States, and from a systematic review of epidemiological articles and research on the global impact of flooding on health.

WHO/Europe has published the results: “Floods in the WHO European Region: health effects and their prevention”.