When natural hazards lead to disasters, they can affect people in many ways, including damaging their housing and negatively impacting their livelihoods. Each year, millions of people are injured or killed as a result of disasters. They can also force people out of their homes: In 2020, 30.7 million new internal displacements linked with disasters, mostly storms or floods, were recorded throughout the world. Between 2010 and 2020, disaster displacements were recorded in 198 countries and territories, making the issue truly global. Such displacement can have severe and long-lasting consequences on physical and mental health, often similar to those of conflict-related displacement. Psychosocial trauma and the deterioration of living standards and housing conditions often alter displaced people’s well-being and their ability to maintain healthy lives or obtain treatment and care. People with disabilities or long-term illnesses are particularly vulnerable in displacement, as are children and older people. Depression and anxiety, malnutrition, communicable diseases, and lack of access to sexual and reproductive health are among the most frequent issues for internally displaced people. The health consequences of displacement linked with disasters vary depending on affected people’s pre-existing conditions and sociodemographic characteristics, the duration and severity of their displacement, and the type of support they are able to access. In cases of mass and protracted displacement, the health of people in communities of refuge and the health systems in the areas of origin and refuge can also be affected, with repercussions on the broader society. Although some of these impacts are relatively frequent and should be systematically considered by national and local governments, humanitarian organizations, and aid providers, each situation requires tailored approaches. Information on the health impacts of displacement remains limited, but the body of knowledge is growing as awareness increases on the scale of current and future displacement crises linked with disasters in a changing climate.
Displacement, Natural Hazards, and Health Consequences
The Impact of Moisture and Temperature on Human Health in Heat Waves
Michael Wehner, Federico Castillo, and Dáithí Stone
Extremely high air temperatures are uncomfortable for everyone. For some segments of the population, they can be deadly. Both the physical and societal aspects of intense heat waves in a changing climate warrant close study. The large-scale meteorological patterns leading to such events lay the framework for understanding their underlying causal mechanisms, while several methods of quantifying the combination of heat and humidity can be used to determine when these patterns result in stressful conditions. We examine four historic heat waves as case studies to illustrate differences in the structure of heat waves and the variety of effects of extreme heat on humans, which are characterized in terms of demographic, geographic, and socioeconomic impacts, including mortality and economic ramifications. Weather station data and climate model projections for the future point to an increase in the frequency and intensity of extreme heat waves as the overall climate gets warmer. Changes in the radiative energy balance of the planet are the principal culprit behind this increase. Quantifying changes in the statistics of extreme heat waves allows for examination of changes in their potential contribution to human health risk. Large-scale mortality during heat waves always occurs within a context of other factors, including public health policy, rural and urban management and planning, and cultural practices. Consequently, the impacts of heat waves can be reduced, and may in many places be manageable into the future, through implementation of such measures as public health warning systems, effective land management, penetration of air conditioning, and increased monitoring of vulnerable or exposed individuals. Given the potential for severe impacts of the more intense heat waves that are virtually certain to occur in the warmer future, it is critical that both the physical and social sciences be considered together to enable society to adapt to these conditions.
Health Care Challenges After Disasters in Lesser Developed Countries
Joseph Kimuli Balikuddembe, Binhua Fu, and Jan D. Reinhardt
A public health disaster occurs when the adverse health effects of an event such as a natural hazard or threat exceed the coping capacity of the affected human population. The coping capacity of the affected population is hereby dependent on available resources including financial and human resources, health infrastructure, as well as knowledge, planning and organizational capabilities, and social capital. Disasters therefore disproportionally affect lesser resourced regions and countries of the world and pose specific challenges to their health systems as well as to the international humanitarian community in terms of dealing with mortality and injuries, communicable and noncommunicable disease, mental health effects, and long-term disability. Challenges for health care delivery in disaster situations in lesser resourced settings include deficiencies in the construction of resilient health care facilities, the lack of disaster response plans, shortage of specialized medical personnel, shortcomings regarding training in disaster response, and scarcity of resources such as medicines and portable medical devices and supplies. Other challenges include the absence of appropriate algorithms for the distribution of scarce resources; lack of coordination of medical teams and other volunteers; limited awareness of particular health issues such as mental health problems or disability and rehabilitation; and lack of plans for evacuation, sheltering, and continuation of treatment of those with preexisting health conditions. Many challenges lesser resourced settings face with regard to health care delivery after disasters such as the organization of mortality management, triage and treatment of the injured, or the delivery of rehabilitative and mental health care cannot be reduced to the lack of baseline resources in terms of health infrastructure, technology, and personnel but are related to the absence of proper planning for future disaster scenarios including implementation strategies and simulation exercises. This not only encompasses the formal drafting of disaster preparedness and response plans, contingency planning of hospitals, and the provision of disaster-related training to health personnel but also in particular the identification and involvement of the potentially and traditionally affected communities and especially vulnerable groups in all the process of disaster risk reduction.
Hurricanes and Health
Caleb Dresser, Satchit Balsari, and Jennifer Leaning
Hurricanes, also referred to as tropical cyclones or typhoons, are powerful storms that originate over warm ocean waters. Throughout history, these storms have had lasting impacts on societies around the world. High winds, rain, storm surges, and floods affect lives, land, and livelihoods and have a variety of effects on human health. The direct health impacts of hurricanes include drowning due to flooding and trauma resulting from storm surges, blown debris, and structural collapse. Systems for detection, forecasting, early warning, and communications can give populations time to make preparations before hurricane landfall. Evacuation, shelter use, and other preparedness efforts have reduced mortality from hurricanes in many parts of Asia and the Americas. Engineered defenses such as sea walls, flood barriers, and raised structures provide added protection in some settings. While effective in the medium term, such approaches are costly and require dedicated resources, and therefore they have not been implemented in many at-risk sites around the world. Indirect health impacts of hurricanes arise from damage to housing, electricity, water, and transportation infrastructure, and from effects on social supports, economies, and healthcare systems. Indirect health impacts can include infectious diseases, carbon monoxide poisoning, trauma sustained during cleanup, mental health effects, exacerbations of chronic disease, and increases in all-cause mortality. Indirect and long-term health consequences are poorly understood because dedicated study of specific impacts has occurred in only a handful of settings, and, given the diverse array of societies and geographies affected by hurricanes, it is unclear how generalizable the results of these studies may be. Policy makers face three interlinked challenges in protecting human health from hurricanes. First, climate change is leading to increased hazards in many locations by altering hurricane dynamics and contributing to sea-level rise. Second, patterns of intensifying coastal settlement and development are expected to increase population exposure. Third, unequal patterns of exposure and impact on specific populations will continue to raise issues of climate and environmental injustice. Situationally appropriate strategies to protect health from future storms will vary widely, as they must both address the locally relevant manifestations of hurricane hazards and adapt to the cultural and economic context of the affected population. In some areas, inexorable ocean encroachment may lead to consideration of managed retreat from high-risk coastlines; in others, the presence of very large coastal urban populations that cannot feasibly evacuate may lead to design and use of vertical shelters for temporary protection during storms. New ideas and programs are urgently needed in many settings to address hazards associated with extreme rainfall, rising seas on floodplains and low-lying islands, landslide risk in areas undergoing rapid deforestation, and structurally unsound housing in some urban settings. Policies to reduce greenhouse gas emissions will help reduce long-term risk from hurricanes and sea-level rise. Without concrete actions to address both hurricane hazards and population vulnerabiliy, the 21st century may be marked by increasingly dangerous hurricanes affecting growing coastal populations that will be left with few viable options for seeking safety.