Climate change and health in Earth's future

Abstract

Threats to health from climate change are increasingly recognized, yet little research into the effects upon health systems is published. However, additional demands on health systems are increasingly documented. Pathways include direct weather impacts, such as amplified heat stress, and altered ecological relationships, including alterations to the distribution and activity of pathogens and vectors. The greatest driver of demand on future health systems from climate change may be the alterations to socioeconomic systems; however, these "tertiary effects" have received less attention in the health literature. Increasing demands on health systems from climate change will impede health system capacity. Changing weather patterns and sea-level rise will reduce food production in many developing countries, thus fostering undernutrition and concomitant disease susceptibility. Associated poverty will impede people's ability to access and support health systems. Climate change will increase migration, potentially exposing migrants to endemic diseases for which they have limited resistance, transporting diseases and fostering conditions conducive to disease transmission. Specific predictions of timing and locations of migration remain elusive, hampering planning and misaligning needs and infrastructure. Food shortages, migration, falling economic activity, and failing government legitimacy following climate change are also "risk multipliers" for conflict. Injuries to combatants, undernutrition, and increased infectious disease will result. Modern conflict often sees health personnel and infrastructure deliberately targeted and disease surveillance and eradication programs obstructed. Climate change will substantially impede economic growth, reducing health system funding and limiting health system adaptation. Modern medical care may be snatched away from millions who recently obtained it.

Climate change-related migration and infectious disease

“…27 Climate-related migration will potentially expose migrants to endemic diseases for which they have limited resistance or socio-cultural experience. 30,31 For example, people migrating through or into areas of high malaria endemicity are at particular risk of infection. 32 Conversely, migrants may bring with them infections such as tuberculosis (TB), hepatitis B and sexually transmissible infections (STIs) that can then spread within the host population.…”

Ch. 6: Climate Impacts on Water-Related Illness. The Impacts of Climate Change on Human Health in the United States: A Scientific Assessment

“…However, few comprehensive or systematic studies have examined the human health impacts of such health-system strain. 203 Particularly in the context of floods and hurricanes, the impacts on health systems from short-and long-term population displacement are not fully understood or well quantified. 67 In addition, the role of future population migration and demographic changes is just beginning to be elucidated in assessments of local adaptive capacity or resilience to the effects of future extreme events.…”

Climate change, conflict and health

“…These harms arise from the direct effects of violence, including against non-combatants and additional strain upon health systems. 11,19 Conflict also creates conditions conducive to infectious diseases, including through poor nutrition, mass migration, overcrowding, and decreased access to clean water, sanitation and shelter. 6 Prevention and control programmes of infectious disease can be diminished or abandoned, potentially hindering some disease eradication efforts.…”

“…8,9 Gradually, some health workers and health journals have responded. 10,11 Methods The authors undertook a systematic review of the health literature dealing with climate changeassociated conflict. A search for the terms (climate change OR global warming) AND (conflict OR war OR violence OR social thresholds) AND (health or med*) in any field on PubMed was conducted.…”