Heatwaves and Their Impacts on Vulnerable Populations

Introduction

Heatwaves are among the deadliest climate-related disasters, causing significant health, social, and economic burdens worldwide. The increasing frequency and intensity of heatwaves due to climate change disproportionately affect vulnerable populations—such as the elderly, children, individuals with pre-existing health conditions, and low-income communities—who often lack the resources or means to protect themselves from extreme heat.

This article explores the science behind heatwaves, their multifaceted impacts on vulnerable communities, and the latest research-driven strategies to mitigate the risks. We draw upon cutting-edge studies to provide an evidence-based understanding of this pressing global issue.

Understanding Heatwaves: A Climate Emergency

Heatwaves are defined as prolonged periods of excessively high temperatures, often accompanied by humidity, that surpass typical seasonal norms. Scientific projections indicate that extreme heat events are becoming more frequent, lasting longer, and reaching unprecedented intensities.

A study published in The Lancet Regional Health (Ulrich et al., 2025) underscores the growing number of acute and prolonged heatwave periods in North America, highlighting their role in exacerbating public health crises, particularly among at-risk populations [Read Here].

How Heatwaves Are Worsening

• The Intergovernmental Panel on Climate Change (IPCC) predicts that, by the end of the 21st century, heatwaves will be more intense and prolonged in most regions of the world.
• Research by Bento et al. (2025) in Frontiers in Climate emphasizes that population exposure to heatwaves is expected to increase significantly, with climate change playing a more significant role than population growth in exacerbating the risks [Read Here].

Who Are the Most Vulnerable?

Not all populations experience heatwaves equally. Vulnerability is shaped by socio-economic factors, underlying health conditions, and environmental exposures.

1. The Elderly and People with Pre-Existing Health Conditions

Older adults and individuals with cardiovascular and respiratory illnesses are more susceptible to heat-related illnesses, including heat exhaustion and stroke. Wang et al. (2025), in a study across ten states in India, found that older adults faced severe psychiatric and physiological outcomes during extreme heat events, emphasizing the urgent need for targeted interventions [Read Here].

2. Pregnant Women and Infants

Heatwaves increase risks for pregnant women, leading to complications such as premature birth and low birth weights. A study by Fatima et al. (2025) found that extreme heat exposure in South Asia had a disproportionate effect on infant birth weights in vulnerable populations [Read Here].

3. Informal and Outdoor Workers

Low-wage workers in construction, agriculture, and street vending are at extreme risk, as their livelihoods require prolonged outdoor exposure. A study on urban heat adaptation in Bangladesh (Shahrujjaman et al., 2025) found that informal workers experienced severe productivity losses and heat-related illnesses due to their lack of access to cooling measures [Read Here].

4. Low-Income Communities and Homeless Populations

People with limited financial resources often live in heat-prone areas, such as urban heat islands, where temperatures are significantly higher than in surrounding regions. Research by Mehryar (2022) highlights that low-income neighborhoods in the UK have fewer green spaces and inadequate infrastructure to withstand extreme heat [Read Here].

5. Children and Schools

Children, particularly those in low-income regions, experience higher risks of dehydration and heatstroke. Schools in developing countries often lack heat resilience infrastructure, putting students at heightened health and learning risks. The WHO has called for immediate action to integrate climate adaptation measures into school systems worldwide.

Heatwaves and Their Health Impacts

The physiological and psychological toll of heatwaves is profound.

Direct Health Impacts

• Heatstroke & Dehydration: As body temperatures rise, heatstroke becomes life-threatening.
• Cardiovascular and Respiratory Complications: Heatwaves exacerbate pre-existing heart and lung conditions.
• Mental Health Deterioration: A study by Rezaali et al. (2025) in the Science of The Total Environment journal found that extreme heat can trigger anxiety, aggression, and increased suicide rates in vulnerable populations [Read Here].

Indirect Health Impacts

• Vector-Borne Diseases: Rising temperatures expand the habitat range of disease-carrying mosquitoes, increasing risks of malaria and dengue.
• Food & Water Insecurity: Extreme heat worsens drought conditions, leading to food shortages and malnutrition.

Economic and Social Consequences

Heatwaves have far-reaching economic and social repercussions.

1. Labor Productivity Loss

The economic productivity of outdoor workers is severely impacted by extreme heat. A study on urban laborers in Bangladesh (Sikder et al., 2025) found that frequent heatwaves caused an annual loss of nearly 12% in work efficiency, highlighting the urgent need for labor protection policies [Read Here].

2. Housing and Energy Crisis

• Urban slums, poorly ventilated apartments, and homes without air conditioning trap heat, exacerbating health risks.
• Power grids fail under excessive demand for cooling, disproportionately affecting marginalized groups.

3. Rising Healthcare Costs

Heat-related illnesses and hospital admissions surge during extreme heat events. The economic burden on healthcare systems is projected to increase as climate change exacerbates heatwave intensity.

Mitigation and Adaptation Strategies

1. Urban Planning and Green Infrastructure

• Expanding tree coverage and implementing urban greening programs can reduce the urban heat island effect.
• Researchers (Justino et al., 2025) found that tree cover in Sub-Saharan Africa significantly mitigated extreme heat effects on vulnerable communities [Read Here].

2. Cooling Centers and Emergency Heat Plans

• Countries like France and Canada have implemented cooling shelters for the public.
• India’s Heat Action Plans (HAPs) are now being expanded across multiple cities to mitigate heatwave fatalities (Dasgupta et al., 2025) [Read Here].

3. Policy Interventions

• Government mandates on workplace safety regulations during extreme heat.
• Policies incentivizing affordable cooling technologies for low-income households.

4. Community Engagement and Public Awareness

• Heatwave early-warning systems should be strengthened.
• Public health campaigns should educate citizens on self-protection measures during extreme heat events.

Conclusion

Heatwaves are no longer rare, seasonal events but a global emergency. With climate change accelerating their frequency and severity, urgent action is needed to safeguard vulnerable populations. From urban greening to policy reforms, an integrated, multi-sectoral approach is essential to building climate resilience.

As policymakers, researchers, and citizens, we must advocate for sustainable and equitable solutions to ensure that the most at-risk populations are not left behind in the face of rising global temperatures.

Cited Studies and Research Articles

1. Ulrich et al. (2025) - Mental health disparities among maternal populations following heatwave exposure [Read Here]
2. Bento et al. (2025) - Projections of population exposure to hot and dry events [Read Here]
3. Wang et al. (2025) - Impact of heat exposure on health outcomes among older adults [Read Here]
4. Fatima et al. (2025) - Disproportionate Climate Burden on Low Birth Weights [Read Here]
5. Justino et al. (2025) - Urban Greening to Mitigate Heat Effects [Read Here]
6. Dasgupta et al. (2025) - India’s Heat Action Plans [Read Here]

By implementing science-backed solutions, we can mitigate the devastating impact of heatwaves and protect those most at risk.