Extreme Weather Events and Health

EWEs: Basics & Climate Link - Weather's Wild Wrath

• EWEs: Significant departures from average weather conditions; severe, unseasonal (e.g., heatwaves, cold waves, intense rainfall, floods, droughts, cyclones, wildfires).
• Climate Change Link: Anthropogenic ↑ GHGs (CO₂, CH₄) trap heat → global warming.
  • Alters energy balance, atmospheric/oceanic circulation.
  • Results in ↑ frequency, intensity, and duration of EWEs globally.

⭐ The IPCC's Sixth Assessment Report (AR6) states it is unequivocal that human influence has warmed the climate, leading to more frequent and intense EWEs.

Heatwaves & Floods: Impacts - Sizzle & Soak Sickness

Heatwaves ("Sizzle Sickness"):

• Direct Effects:
  • Heat Cramps: Muscle spasms.
  • Heat Exhaustion: Fatigue, nausea, temp < 40°C.
  • Heat Stroke: Emergency! Temp > 40°C, CNS dysfunction (delirium, coma), anhidrosis/sweating. Rapid cooling vital.
  • Heat Syncope: Fainting.
• Indirect Effects:
  • Exacerbates CVD, respiratory, renal conditions.
  • ↑Air pollution (ozone, PM2.5).
• Vulnerable: Elderly, children, outdoor workers, pre-existing illnesses.

⭐ Heat stroke: core temp > 40°C + CNS dysfunction. Differentiate classic (anhidrotic) vs. exertional (sweating). Rapid cooling is life-saving.

Floods ("Soak Sickness"):

• Immediate: Drowning, injuries.
• Medium-Term (Post-Flood):
  • Water-borne: Cholera, Typhoid, Leptospirosis, Hepatitis A/E, diarrhea.
  • Vector-borne (stagnant water): Malaria, Dengue, Chikungunya.
  • Skin/eye infections. Leptospirosis (rodent-borne).
• Long-Term: Mental health (PTSD, anxiety), displacement, malnutrition.

Droughts, Storms, Wildfires: Impacts - Dry, Blown & Burnt Blues

• Droughts:
  • ↓Food security → Malnutrition, stunting
  • Water scarcity → ↑Water-borne diseases (cholera, typhoid), dehydration
  • Air quality ↓ → Respiratory issues (dust, fungal spores like Coccidioidomycosis)
  • Mental health: Anxiety, depression from agricultural/economic losses
  • Vector-borne diseases: Altered vector ecology (e.g., West Nile Virus)
• Storms (Cyclones, Hurricanes, Tornadoes):
  • Physical trauma: Injuries, drowning
  • Infections: ↑Leptospirosis, cholera, diarrheal diseases (water contamination)
  • Vector-borne: ↑Mosquito breeding sites (dengue, malaria)
  • Mental health: PTSD, anxiety, depression
  • Infrastructure damage: Disrupted health services, power outages
• Wildfires:
  • Burns & trauma
  • Respiratory distress: Smoke inhalation (particulate matter PM2.5) → Asthma/COPD exacerbation, bronchitis
  • Cardiovascular effects: ↑Risk of MI, stroke
  • Eye irritation, conjunctivitis
  • Mental health: Stress, anxiety, PTSD, displacement

⭐ Wildfire smoke, rich in PM2.5, significantly worsens pre-existing respiratory conditions like asthma and COPD, and increases cardiovascular morbidity and mortality.

EWEs: Vulnerability & Response - Shielding & Shaping Safety

• Key Vulnerabilities:
  • Physiological: Elderly (>65 yrs), children (<5 yrs), pregnant women.
  • Pathological: Chronic diseases (CVD, respiratory, diabetes), mental illness.
  • Socio-economic: Poverty, poor housing, illiteracy, social isolation, outdoor workers.
  • Geographic: Coastal regions, floodplains, urban heat islands, remote areas.
• Public Health Strategies (4 Pillars):
  • Preparedness: Robust Early Warning Systems (EWS), Vulnerability & Risk Assessment (VRA), capacity building.
  • Prevention & Mitigation: Climate-resilient health infrastructure, inter-sectoral coordination (NDMA, IMD), Heat Action Plans (HAPs).
  • Response: Rapid needs assessment, emergency medical services, disease surveillance (vector-borne, water-borne).
  • Recovery: Provision of safe water/sanitation/shelter, psychosocial support, restoring health services.

⭐ India's National Programme on Climate Change and Human Health (NPCCHH) focuses on strengthening health system preparedness and response.

📌 ADAPT: Assess risks, Develop plans, Activate EWS, Protect vulnerable, Train personnel.

High-Yield Points - ⚡ Biggest Takeaways

• Heatwaves significantly increase risks of heat stroke, dehydration, and cardiovascular events.
• Floods are major drivers of water-borne diseases (cholera, leptospirosis) and vector-borne diseases like dengue.
• Droughts contribute to malnutrition, food insecurity, and increased risk of communicable diseases.
• Cyclones cause traumatic injuries, drowning, and outbreaks of vector-borne diseases post-impact.
• Extreme weather often displaces populations, increasing mental health burdens and infectious disease spread.
• Vulnerable populations (elderly, children, chronic illness patients) bear the highest health burden.