Climate Crisis and Its Impacts on Health “The Future Is Now”*

Introduction

Climate change is no longer solely an environmental issue; the World Health Organization has officially declared it a health crisis.¹ The summer of 2024 has been recorded as the hottest in history.² On November 12, 2021, Canadian physician Dr. Kyle Merritt made headlines by diagnosing a patient suffering from heat-induced respiratory distress with “climate change,” marking the first time this was formally acknowledged as a medical diagnosis.³ From heatwaves to floods, hurricanes to wildfires, the increasing frequency and severity of extreme weather events continue to threaten human health.^1,3-6 Current data reveals that 3.6 billion people live in areas highly vulnerable to climate impacts. Given that socioeconomic conditions have long influenced the performance of health systems, the climate crisis emerges as a critical threat multiplier, especially in fragile regions. Children are among the most affected, due to their underdeveloped immune systems, higher metabolic needs, sensitivity to environmental toxins, and smaller airways.^7,8 Thus, climate change is no longer outside the scope of pediatric care—it is a pressing concern directly influencing clinical practice and child health policy.

Health Implications of the Climate Crisis

Climate change threatens human health through various environmental disruptions such as rising temperatures, extreme weather events, and air and water pollution. Heatwaves exacerbate cardiovascular and respiratory conditions, while compromised food and water security increases risks of malnutrition and infectious diseases.⁹ Vector-borne diseases like malaria and dengue are expanding geographically, allergic disorders are becoming more prevalent, and post-disaster trauma is having widespread psychological impacts.^10,11 Vulnerable groups such as children, the elderly, those with chronic illnesses, and low-income communities bear the brunt of these effects, framing climate change as a global public health emergency.

Children are particularly susceptible due to physiological and developmental vulnerabilities including immature immune systems, faster respiratory rates, higher metabolic demands, and more permeable skin barriers.^{7 8} Disruptions to healthcare access, declining vaccination rates, and education losses further exacerbate long-term consequences.

Extreme weather events—heatwaves, wildfires, droughts, floods, and storms—are increasingly affecting child health directly and indirectly.^7,12-15 According to UNICEF, 1.2 billion children globally are exposed to at least one climate-related environmental threat, including water scarcity, air pollution, infectious disease exposure, and food insecurity.⁷

As of 2024, escalating environmental stressors such as extreme heat, air pollution, and resource insecurity have led to a marked rise in respiratory and allergic diseases commonly seen in pediatric settings.

The Rise of Allergic Diseases and Their Link to Climate Change

Global warming has prolonged pollen seasons, increased the allergenicity of pollens, and contributed to the rising incidence of allergic conditions. A longitudinal study conducted across 17 cities in the Northern Hemisphere, monitoring data over a span of 10 to 28 years, revealed a 0.9-day annual increase in pollen days, equating to nearly an extra month of pollen exposure over 30 years.⁹

This prolonged exposure exacerbates conditions such as asthma, allergic rhinitis, and atopic dermatitis. Urbanization-driven factors—exhaust fumes, elevated CO₂ levels, and the urban heat island effect—amplify pollen allergenicity. Increased ozone and PM2.5 levels intensify allergic sensitization and inflammatory responses.^9-11,16

One notable phenomenon is “thunderstorm asthma,” where sudden dispersal of pollen particles during storms leads to asthma attacks. In Louisiana, data from 63,000 asthma patients showed a 14.5% increase in emergency visits per 1 g/m²/s increase in rainfall on stormy days.^12,17

Climate Change, Wildfires, and Health Impacts

Rising temperatures and droughts have increased the frequency of wildfires. The particulate matter, ozone, and carbon monoxide released during wildfires pose serious health risks, especially for young children. A California-based study observed a 10.3% rise in asthma-related emergency visits among children aged 0–5 during days with PM2.5 levels in the 98th percentile.¹³

Post-disaster indoor environments are also affected.¹⁸ Mold spores, dust mites, and rodents proliferate, increasing indoor allergen loads. Studies following Hurricanes Katrina and Maria documented a marked decline in indoor air quality, correlating with a rise in respiratory allergies and asthma exacerbations.

Emerging Allergens and Shifting Geographic Patterns

Rising global temperatures have introduced new allergens into previously unaffected regions. For instance, Alaska reported its first bee-sting-induced death in 2006, and species such as Vespula and Polistes wasps are now found in increasingly northern parts of Europe.¹⁹

Heat and humidity are also linked to the spread of alpha-gal allergy, caused by tick bites and characterized by delayed anaphylaxis following red meat consumption. Climate change is expanding the habitats of such vectors, introducing novel risks as red meat allergy.²⁰

Pollen-Food Cross-Reactivity and Eosinophilic Esophagitis

Structural similarities between pollen proteins and certain fruits, vegetables, and nuts can cause cross-reactive food allergies, also known as pollen-food syndrome.^21,22 Symptoms range from oral itching to, in rare cases, systemic reactions, with severity often peaking during pollen season.

Similarly, eosinophilic esophagitis (EoE)—a chronic, immune-mediated esophageal disease—has become more prevalent.^21-23,24 In allergic individuals, EoE symptoms like dysphagia, abdominal pain, and reflux worsen during pollen season due to increased gastrointestinal inflammation.

Impact on Skin Barrier and Atopic Dermatitis

Environmental pollutants and heat impair the skin barrier, leading to a surge in atopic dermatitis cases, particularly among infants and toddlers.²⁵ A compromised skin barrier facilitates the transdermal penetration of allergens like dust mites, pollen, and pet dander, increasing the likelihood of developing asthma and allergic rhinitis later in life.

These findings position the climate crisis as not only an environmental but also an immunological and allergic health threat. Pediatric clinical awareness and climate-adaptive health policies must be urgently advanced to prevent today’s symptoms from becoming tomorrow’s complex health burdens.

The Climate Clinic: A Case Study from Türkiye

Launched by Yuvam Dünya in collaboration with Hacettepe University and Koç University, Türkiye’s first “Climate Clinic” aims to engage students in medicine and health sciences in building climate-resilient healthcare systems. Through capacity-building, training, and research, the initiative addresses climate-sensitive illnesses, supports early warning systems, and informs climate-conscious urban planning. By integrating education, research, and advocacy, the Climate Clinic is a significant step toward strengthening national climate adaptation capacity in healthcare.

The Role of Health Professionals: Trust and Communication

Healthcare professionals are among the most trusted figures in society. Marketing strategies frequently rely on their endorsements to build credibility. Their influence extends beyond clinical advice to shape public behavior and societal norms.

Similarly, in the context of climate change, their guidance can be pivotal. Statements like “To protect your child’s health, try to open the refrigerator less frequently” or “Limit outdoor playtime on days with high air pollution” can drive meaningful change at both individual and societal levels.

However, fear-based messaging should be avoided in favor of solution-oriented and hopeful communication. Just as children with diabetes are encouraged to explore healthy alternatives rather than face blanket bans, climate messaging should be grounded in knowledge and participation, not prohibition or panic.

Conclusion

The climate crisis is a multidimensional public health emergency, impacting children’s physical, psychological, and social well-being. Combating it requires coordinated action among pediatricians, health professionals, and policymakers. Climate-proofing health systems, updating medical curricula, and empowering trusted health professionals as climate advocates are essential to securing the health of future generations.

Funding Statement

The authors declared that this study has received no financial support.

Data Availability Statement:

The data that support the findings of this study are available on request from the corresponding author.