 "Heat, smog, dengue: How climate change became a health threat in 2025")
The year 2025 wasn’t just hotter, dustier or wetter than usual, it felt harder on the body too. More people around fell ill. Fevers lingered. Breathing felt heavier. Food upset stomachs more often. Sleep broke more easily. Anxiety simmered under the surface.
In 2025, weather patterns reshaped the country’s disease profile. From dengue moving into new territories to heat becoming a medical emergency, climate-linked illness emerged as one of the most important public health stories of the year.
Vector-borne diseases expanded beyond seasons and geographies
Dengue, malaria and chikungunya are no longer “seasonal” problems.
Traditionally, vector-borne diseases followed predictable patterns. Monsoons brought mosquitoes, winters brought relief. This year, those boundaries blurred. Dengue cases appeared earlier, lasted longer and surfaced in regions that previously saw little or none.
Warmer temperatures, erratic rainfall and prolonged humidity created ideal breeding conditions for mosquitoes almost year-round. Urban flooding after intense downpours left behind stagnant water in construction sites, basements and even rooftop tanks. Rural areas, meanwhile, saw shifting malaria patterns as vectors adapted to changing ecosystems.
Toxic air intensified chronic and everyday health problems
Air pollution has long been India’s most visible environmental health crisis. In 2025, its impact felt sharper as hospital admissions for respiratory issues surged in Delhi-NCR and other urban centres.
Doctors reported more severe asthma attacks, harder-to-control chronic obstructive pulmonary disease symptoms, higher cardiac stress and a rise in respiratory infections that took longer to resolve.
Even people without diagnosed lung disease complained of fatigue, headaches, poor sleep and persistent throat irritation. ALSO READ | 10 studies that redefined what healthy living means for Indians in 2025
Extreme heat became India’s fastest-growing health emergency
Heat was the quiet villain of the year.
India recorded some of its longest and most intense heatwaves on record, with night-time temperatures staying dangerously high. This mattered because the human body relies on cooler nights to recover from daytime heat stress.
Hospitals saw spikes in dehydration, kidney injury, heat exhaustion and heatstroke, along with increases in heart attacks, strokes and pregnancy complications, all conditions worsened by extreme heat.
Extreme weather drove a surge in food- and water-borne infections
Heavy rainfall, floods and cyclones do not just damage infrastructure; they destabilise hygiene systems.
This year, health departments reported spikes in diarrhoeal diseases, typhoid, hepatitis A and E, and parasitic infections following extreme weather events. Floodwaters contaminated drinking sources, overwhelmed sewage systems and disrupted food storage and supply chains.
Climate stress quietly worsened India’s mental health burden
The year also saw growing recognition of the mental health toll of climate instability, ranging from anxiety during prolonged heat to distress after floods, displacement or crop loss.
Psychiatrists and counsellors reported rising cases of sleep disorders, irritability, low mood and anxiety linked to prolonged weather stress. Farmers faced emotional exhaustion from repeated crop failures. Urban residents described a constant low-grade stress driven by heat, pollution and uncertainty.
The biggest lesson 2025 taught was that health can no longer be separated from climate.
Diseases once considered sporadic or seasonal are becoming persistent as environmental exposures compound lifestyle and genetic risks. According to doctors, this means individuals must pay closer attention to hydration, heat protection, air-quality alerts and food safety as part of everyday health habits.