Heat report highlights growing exposure among infants and older adults
Where it stands
Infants and older adults are spending far more time exposed to heatwaves as the climate warms. The Lancet Countdown’s 28 October 2026 report examines this risk across the world. Its findings show why health services must prepare for repeated periods of dangerous heat. The finding concerns exposure to dangerous heat, rather than a count of people who died. Researchers combine the number of vulnerable people with the number of heatwave days they experienced. A large population can therefore produce a high national total even when another country has more heatwave days per person. Worldwide, people aged 65 and above experienced an average of 12.8 heatwave days in 2025. Infants under one experienced 8.7 days. These are global averages, not figures for India alone. Exposure was lower than the record levels of 2024, but remained among the highest measured. For families and health services, the concern is that the people least able to cope face repeated periods of heat. Older adults may have existing illnesses, while infants depend on others to keep them safe. Cooling access, shade and health services prepared for heat can reduce harm. The report measures a growing risk; it does not announce a new Indian benefit or health programme.
Background
The body needs to release heat to keep its internal temperature within a safe range. Hot surroundings make that harder, and high humidity can reduce the cooling achieved through sweating. If heat builds up faster than the body can lose it, organs come under strain. People do not face that strain equally. Age, existing illness, work and housing all affect the ability to cope. Someone with access to a cool room can escape conditions that another person must endure outdoors. Infants also cannot arrange their own protection, so their safety depends on caregivers and suitable surroundings. A heatwave adds duration to the problem. Several unusually hot days can be especially demanding when nights also remain hot. The Lancet indicator therefore counts periods when both daytime and night-time temperatures exceed unusually high local thresholds. Measuring exposure helps identify the scale of the challenge before every consequence appears in hospital records. But exposure is only one part of risk. The indicator does not capture every difference in humidity, neighbourhood conditions or access to cooling. Health planning must combine the broad warning with local information about who needs help and where services are weakest.
How it developed
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28 October 2026: report releasedHow it started
The report distinguishes exposure from illness and death
The 2026 assessment examines heatwave exposure among infants under one and adults aged 65 and above. Its indicator counts unusually hot days and nights against a local historical baseline. Global exposure in 2025 remained very high despite falling from the 2024 peak. The global averages do not show how many heatwave days each person in India or another country experienced. The results help explain why heat protection must account for age and living conditions.
Why it matters for UPSC
Connect climate change with unequal health risks and adaptation. Explain why total person-days differ from the number of affected people and exposure per person. Relate heat warnings to housing, public spaces and health-service preparedness.
Key terms
Sources (3)
- Lancet Countdown · official · 2026 heatwave exposure indicator: findings and methods28 Oct, 12:34 pm
- World Health Organization · official · Climate change, heat and health28 Oct, 12:34 pm
- PTI / Business Standard · India among countries with high heatwave exposure for infants and older adults28 Oct, 12:34 pm