Context:

• There is scientific consensus that 2023 was the hottest year ever in the planet’s recorded history. 
• The consequences of climate change, mostly mediated through global warming, adversely affect human, animal and plant health in several ways.

Impacts:

• Direct effects of heat exposure: Increased risk of heat exhaustion, heat stroke, and circulatory failure, particularly among vulnerable populations such as infants, the elderly, and those with preexisting health conditions.
• Non-communicable diseases (NCDs): Exacerbation of conditions like strokes, heart attacks, diabetes, respiratory diseases, and cancers due to prolonged heat exposure.
• Vector-borne and water-borne infections: Changes in climate patterns can affect the distribution and prevalence of disease-carrying vectors like mosquitoes and waterborne pathogens, increasing the risk of diseases such as malaria, dengue and cholera.
• Mental health disorders: Increased stress, anxiety, and trauma resulting from extreme weather events, displacement, and loss of livelihoods due to climate change impacts.
• Air pollution: Collaboration between air pollution and heat can worsen respiratory conditions and cardiovascular health, leading to an increased risk of lung and heart diseases.
  • Wildfires triggered by excessive heat release particulate matter (PM 2.5) and toxic chemicals (ozone, carbon monoxide, polycyclic aromatic compounds and nitrogen dioxide) can cause extensive inflammation, increasing the risk of cardiovascular disease (heart attacks, strokes, heart failure), respiratory disease, diabetes and pre-diabetes. 
  • Chemicals like benzene and formaldehyde (also present in wildfire emissions) increase the risk of cancer.
• Food and nutrition insecurity: Reduced crop yields, decreased nutrient quality of crops, and disruptions to food systems can lead to malnutrition, deficiencies in essential nutrients like zinc, protein, and iron, and an increased risk of cardiovascular diseases and diabetes.
  • Countries in South Asia and sub-Saharan Africa currently grow staples (like rice and wheat) at the highest levels of heat tolerance. 
  • A further increase of 1 degree centigrade will lower their yield by 10 per cent. The crops will also be more deficient in zinc, protein and iron. 
  • The Data Sciences Centre of Columbia University has estimated that if global warming continues unabated, India of 2050 will have 49 million more zinc deficient persons and 38.2 million new protein deficient persons, while 106.1 million children and 396 million women would be iron deficient. 
  • Protective foods like fruit, vegetables and fish would be depleted. These foods reduce the risk of cardiovascular disease and diabetes. 
  • Rising ocean temperatures will flood coastal agriculture and also reduce fish yields. This can further reduce the protein intake.
• Water scarcity: Changes in precipitation patterns and increased evaporation due to higher temperatures can lead to water scarcity, impacting hygiene, sanitation, and access to clean drinking water, thus increasing the risk of water-borne diseases.
• Displacement and migration: Climate-related events such as extreme weather events and sea-level rise can lead to displacement and migration, putting pressure on healthcare systems and increasing the risk of disease outbreaks in refugee populations.
• Increased healthcare demands: Extreme weather events and heat waves can strain healthcare infrastructure, supply chains, and personnel, leading to increased demand for healthcare services, especially during emergencies.

Way Forward: 

• Even as we must try energetically to mitigate the drivers of climate change and global warming, we must prepare adaptation plans. 
• These will include heat action plans designed specifically for urban and rural areas, climate smart and climate resilient food and healthcare systems, education of public and healthcare providers and anticipatory planning to meet the increased healthcare demands that heat waves will bring in their wake. 
• Heat shelters, water stations, heat reflective roofs and wall paints for housing, well ventilated homes and an increase in green spaces must become part of urban planning. 
• Personal protection through light coloured, loose fitting clothes, umbrellas or caps are helpful. The most important personal protection measure is to drink lots of water.