Climate change profoundly impacts human health, causing direct and indirect effects. From heat-related illnesses to the spread of vector-borne diseases, these impacts touch every aspect of our well-being, including food security and mental health.

Certain populations are more vulnerable to climate change's health effects. The elderly, children, and those with pre-existing conditions face greater risks. Epidemiologists play a crucial role in studying these impacts, developing strategies, and informing policies to protect public health.

Climate Change and Human Health

Health impacts of climate change

• Direct impacts
  • Heat-related illnesses and deaths escalate as temperatures rise causing heat exhaustion and heat stroke (Chicago 1995 heatwave)
  • Injuries and fatalities from extreme weather events intensify due to increased frequency and severity of storms (Hurricane Katrina)
• Indirect impacts
  • Vector-borne diseases spread to new areas as climate shifts expand habitats for disease-carrying insects (malaria in highland areas)
  • Water-borne diseases surge following floods contaminating water supplies with pathogens (cholera outbreaks after monsoons)
  • Air quality-related health issues worsen from increased pollutants and allergens triggering asthma attacks and respiratory infections
• Food security and nutrition
  • Crop yield reductions threaten food availability as droughts and extreme weather disrupt agriculture (maize production in Africa)
  • Altered nutrient content in food occurs as CO2 levels rise reducing protein and mineral concentrations in staple crops (rice, wheat)
• Mental health effects
  • Anxiety and depression related to climate change increase as people worry about environmental degradation and future uncertainties
  • Post-traumatic stress from extreme weather events lingers in survivors of disasters (Hurricane Maria in Puerto Rico)

Vulnerable populations for climate effects

• Elderly individuals struggle with thermoregulation and have higher prevalence of chronic conditions exacerbated by climate stressors
• Children face greater risks due to developing immune systems and higher respiratory rates making them susceptible to air pollution
• Individuals with pre-existing health conditions experience worsened symptoms during extreme weather or poor air quality days
• Low-income communities lack resources for adequate housing, healthcare access, and climate adaptation measures
• Outdoor workers endure increased exposure to extreme temperatures raising their risk of heat-related illnesses (construction workers)
• Coastal and low-lying area residents face heightened danger from rising sea levels, flooding, and intensified storm surges
• Indigenous populations relying on traditional food sources and ecosystems suffer as climate change disrupts their way of life

Epidemiology and Climate Change

Epidemiology in climate change studies

• Surveillance and monitoring track disease patterns and emerging health threats related to changing climate conditions
• Risk assessment quantifies health risks associated with climate change projecting future impacts on populations
• Study design and implementation
  1. Conduct longitudinal studies to assess long-term effects of climate change on health
  2. Design cross-sectional studies for immediate impacts of extreme weather events
• Data analysis and interpretation identify correlations between climate variables and health outcomes controlling for confounding factors
• Modeling and forecasting develop predictive models for future health scenarios simulating potential intervention outcomes

Strategies for climate health adaptation

• Mitigation strategies
  • Reducing greenhouse gas emissions through renewable energy sources (solar, wind) and energy-efficient technologies
  • Enhancing carbon sinks via reforestation initiatives and protecting wetlands to absorb atmospheric CO2
• Adaptation strategies
  • Strengthening health systems by improving disease surveillance and enhancing emergency preparedness
  • Urban planning implements heat-resistant building designs and creates green spaces for cooling and air quality improvement
  • Water management develops drought-resistant crops and improves water storage systems to ensure clean water access
  • Public education raises awareness about climate-related health risks and promotes adaptive behaviors
• Policy interventions
  • Implementing health-protective policies such as heat action plans and air quality regulations to safeguard public health
  • Integrating health considerations into climate change policies through health impact assessments for climate-related decisions
• International cooperation facilitates sharing of data, best practices, and support to vulnerable nations addressing global climate challenges