~ Climate Change Impacts on Public Health

Climate change affects public health in a number of ways. The complex interactions between climatic and non-climatic stressors such as increasing air temperatures, changes in precipitation regimes, air and water pollution, and social and economic inequities drive myriad health responses in individuals and communities. Over the last 35+ years, the 16 states included in this project have been affected by over 790 weather-related disasters, including droughts, wildfires, flooding, and severe storms.3

Climate-driven changes are contributing to decreased air quality; increased ground level ozone and particulate matter; increased asthma attacks and premature deaths; prolonged pollen and allergy seasons; increased mold growth and persistence due to increased temperatures and precipitation; heat-related illnesses (e.g., heat exhaustion, heat stroke) and death; and susceptibility to water-, food-, and vector-borne diseases. Additional information on observed and projected future climatic changes in the United States4 and effects on public health5,6 have been well-documented elsewhere.

Human health is a product of interactions between the natural, built, and social environments. However, climate-driven health risks are not equally distributed across communities. The state of human health depends on interactions between exposure to the physical environment, vulnerability to threats, and human behavior. For example, inequitable living conditions may lead to increased risk from flooding or high levels of exposure to air pollution. The vulnerability of a population to climate-related public health impacts is influenced by social determinants that shape the degree to which they are able to resist, promote resilience, and respond to threats. Social determinants of health (SDOH) greatly affect health inequalities as they influence both the ways in which people function in society and the distributions of wealth, power, and resources.7

The U.S. Office of Disease Prevention and Health Promotion developed five SDOH categories as part of the Healthy People 2020 initiative: economic stability, education, social and community context, health and health care, and neighborhood and built environment.8 Variables within these categories include living wage income, gender, race, location, current health and healthcare status, age, food insecurity, transportation options, safe drinking water and water supply, and air quality. Through investigating determinants of health and vulnerabilities impacting exposure and adaptive capacity, the needs of communities can better be addressed in response to climate-related threats to environmental and public health, health services, and social justice. Key stressors and effects on public health and healthcare services are presented in Table 1. This list is not meant to be comprehensive as more detailed analyses on climatic effects on public health and healthcare services are presented elsewhere.

Table 1. Examples of climate & non-climate factors that affect public health & healthcare services

Exposure Pathways

  • Air Quality
  • Extreme Heat
  • Flooding
  • Water Quality & Supply
  • Vector Ecology
  • Food Quality & Supply

Climatic & Non-Climatic Drivers & Stressors

  • Increasing air temperatures and heat waves
  • Increasing water temperatures
  • Changes in precipitation amount and timing
  • Increasing ground-level ozone and particulate matter
  • Wildfire
  • Drought
  • Sea level rise and saltwater intrusion
  • Frequency and severity of storms
  • Harmful algal blooms
  • Range shifts of pests
  • Airborne allergens (e.g., ragweed), toxins, and particulate matter
  • Flooding and land-based runoff of pollutants and pathogens
  • Urban heat islands

Social Determinants

  • Race and ethnicity
  • Age and gender
  • Economic stability (e.g., living wage income)
  • Housing and transportation options
  • Poverty
  • Education
  • Access to services
  • Pre-existing health conditions
  • Geographic location

Examples of Effects on Health & Healthcare Services

  • Respiratory and cardiovascular illnesses
  • Heat-related illnesses and mortality
  • Injuries and fatalities
  • Neurological diseases
  • Vector-borne diseases (e.g., Lyme disease, West Nile virus, Zika, hantavirus, leptospirosis, etc.)
  • Emotional and psychological illnesses and grief
  • Negative birth outcomes
  • Displacement of individuals and communities
  • Food and water contamination (e.g., Salmonella, gastrointestinal illnesses, mercury contamination in seafood)
  • Food security and nutrition issues (e.g., disruption in food supply chain due to inaccessible transportation routes from extreme events)
  • Disruption or damage to healthcare infrastructure
  • Stress on energy systems that may lead to power outages