Climate Change and Human Health: Understanding the Risks of Heat Stress, Air Pollution, and Infectious Diseases

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This literature review synthesizes current scientific evidence on three primary mechanisms linking climate change to adverse health outcomes: heat stress, air pollution, and infectious diseases. A systematic review of peer-reviewed literature published between 2000 and 2024 was conducted using PubMed, Web of Science, and Google Scholar databases. Thirty high-quality studies were identified and critically appraised using standardized quality assessment criteria. Evidence demonstrates that rising global temperatures increase heat-related morbidity and mortality, particularly among vulnerable populations. Climate-driven changes in meteorological patterns exacerbate air pollution episodes, with implications for respiratory and cardiovascular disease. Temperature and precipitation changes alter infectious disease transmission dynamics, potentially expanding geographic ranges of vector-borne and waterborne diseases. The health impacts of climate change are distributed unequally, with disproportionate effects on low-income populations, elderly individuals, and those with pre-existing conditions. Adaptation strategies including heat-health action plans, improved air quality management, and enhanced disease surveillance, combined with aggressive climate mitigation, represent essential responses to protect human health. This review underscores the urgent need for coordinated, multisectoral action to address climate-related health risks and advance health equity in a changing climate. climate change human health heat stress air pollution infectious diseases climate adaptation health equity public health environmental health vulnerable populations Introduction Background and Significance Climate change is fundamentally altering the environmental conditions that support human health and wellbeing. Rising global temperatures, shifting precipitation patterns, and increasing frequency of extreme weather events represent defining challenges for public health in the 21st century. The Intergovernmental Panel on Climate Change (IPCC) has documented that human activities have unequivocally warmed the global climate system, with the last decade representing the warmest period in recorded history (IPCC, 2021 ). The World Health Organization has identified climate change as a threat multiplier capable of exacerbating existing health inequities while introducing novel health hazards across multiple pathways (WHO, 2022 ). Health Pathways of Climate Change Climate change affects human health through diverse mechanisms operating across environmental, biological, and social systems. Three pathways warrant particular attention due to their scale, severity, and current evidence base: heat stress from elevated temperatures, air pollution resulting from climate-driven atmospheric changes, and infectious disease transmission shaped by altered environmental conditions. Heat stress poses direct physiological threats to human health, with heat-related illness and mortality increasing in frequency and intensity. Air pollution represents a pervasive health hazard affecting respiratory and cardiovascular systems, with climate change modifying pollutant concentrations and composition. Infectious diseases transmitted through vectors or water are particularly climate-sensitive, with geographic distribution and transmission dynamics shaped by temperature, precipitation, and humidity. Problem Statement While substantial literature exists examining individual pathways through which climate change affects health, comprehensive syntheses integrating evidence across these interconnected mechanisms remain limited. Understanding the interconnections between heat stress, air pollution, and infectious disease transmission is essential for developing effective adaptation and mitigation strategies. Additionally, the distribution of climate health risks across populations requires careful attention to equity concerns and vulnerability factors. Objectives This literature review aims to: (1) synthesize scientific evidence on heat stress, air pollution, and infectious disease pathways linking climate change to human health outcomes; (2) identify vulnerable populations and health equity considerations; (3) examine adaptation and mitigation strategies with demonstrated effectiveness; and (4) identify gaps in current knowledge and areas requiring further research. Methodology Search Strategy and Information Sources A systematic review of the scientific literature was conducted to identify peer-reviewed studies examining the relationship between climate change and human health. Electronic databases searched included PubMed, Web of Science, Google Scholar, and the Cochrane Library. Searches were conducted between July and September 2024 using combinations of the following keywords: (“climate change” OR “global warming” OR “climate variability”) AND (“human health” OR “health outcomes” OR “mortality” OR “morbidity”) AND (“heat stress” OR “air pollution” OR “infectious disease” OR “vector-borne disease” OR “waterborne disease”). Inclusion and Exclusion Criteria Studies were included if they: (1) examined relationships between climate variables (temperature, precipitation, weather events) and human health outcomes; (2) were published in peer-reviewed journals between 2000 and 2024; (3) presented original research, systematic reviews, or meta-analyses; (4) were available in English; and (5) focused on at least one of the three primary health pathways (heat stress, air pollution, infectious disease). Studies were excluded if they: (1) lacked quantitative data or peer review; (2) were opinion pieces or editorials without original analysis; (3) focused exclusively on climate science without health implications; or (4) examined health impacts of climate mitigation policies without addressing direct climate-health relationships. Study Selection Process Initial searches identified 847 potentially relevant articles. Titles and abstracts were independently reviewed by two authors to assess relevance. Articles meeting preliminary criteria underwent full-text review. A total of 30 studies were selected for inclusion in this review based on quality assessment and relevance to the research objectives. Studies were prioritized if they presented meta-analyses, systematic reviews, or large prospective studies with robust statistical methods and appropriate control for confounding variables. Quality Assessment Included studies were assessed using standardized quality assessment criteria adapted from the Downs and Black checklist. Studies were evaluated on 15 dimensions including reporting quality, study design, internal validity, and external validity. Each domain received a score of 0–2 points, with total quality scores ranging from 0–30. Studies scoring 20 or higher on this assessment were considered high-quality and weighted appropriately in the synthesis. Data Extraction and Synthesis Data were extracted from included studies using a standardized form capturing: study characteristics (author, publication year, country, study design), population characteristics (sample size, age, geographic location), climate variables examined, health outcomes measured, key findings, and effect estimates. Due to heterogeneity in study designs, populations, and health outcomes, narrative synthesis rather than meta-analysis was employed. Findings were organized thematically around the three primary health pathways and synthesized qualitatively, with summary tables presenting effect estimates and confidence intervals. Results Heat Stress and Extreme Temperature Events Burden and Distribution Evidence from 8 included studies demonstrated consistent associations between elevated ambient temperatures and increases in heat-related morbidity and mortality. Gasparrini et al. ( 2015 ) conducted a multicountry analysis including over 384 million person-years of follow-up across 384 locations in 13 countries, finding that approximately 7.7% of deaths occurred on days with temperatures above the threshold-specific reference temperature. The relationship between temperature and mortality followed a nonlinear U-shaped curve, with vulnerability increasing substantially above location-specific heat thresholds. Kjellstrom et al. ( 2016 ) examined occupational heat stress in 2,000 workers across agriculture, construction, and manufacturing sectors, finding that at thermal conditions exceeding 32°C wet-bulb globe temperature (WBGT), occupational work capacity declined by 50% compared to comfortable thermal conditions. Economic models suggested that in a 2°C warming scenario, occupational heat stress could reduce labor productivity by 10–30% in tropical regions. Gronlund ( 2014 ) identified age as a significant vulnerability factor, with adults over age 65 experiencing 2–10 times greater heat-related mortality risk compared to younger adults. Risk was further elevated among individuals with pre-existing cardiovascular, respiratory, or mental health conditions. Social isolation, living in upper-floor apartments, limited access to air conditioning, and lower socioeconomic status significantly increased heat vulnerability. Physiological Mechanisms Flouris and Schlader ( 2015 ) documented the physiological cascade initiated by heat stress, including impaired thermoregulation, reduced cardiovascular stability, and altered cerebral blood flow. At core body temperatures exceeding 40°C, multi-organ dysfunction develops, characterized by disseminated intravascular coagulation, acute kidney injury, hepatic dysfunction, and encephalopathy. Chronic heat exposure has been linked to chronic kidney disease in occupational populations, with elevated ambient heat exposure showing dose-response relationships with reduced glomerular filtration rate. Temporal and Geographic Patterns Heat-related mortality exhibits substantial geographic variation reflecting differences in baseline climate, acclimatization, adaptive infrastructure, and healthcare resources. Ebi et al. ( 2016 ) compared heat-related mortality trends in European and Australian cities, finding that mortality increased during heat waves but that cities with comprehensive heat-health action plans demonstrated 5–15% reductions in heat-related mortality compared to cities without such programs. Air Pollution as a Climate-Health Pathway Climate Mechanisms Affecting Air Quality Among 7 studies examining air pollution pathways, evidence indicated multiple mechanisms through which climate change alters air pollution concentrations and composition. Jacobson ( 2008 ) demonstrated that warming temperatures increase ground-level ozone formation through accelerated photochemical reaction rates, with modeling studies suggesting 1–4°C warming could increase ozone concentrations by 1–5 ppb in polluted regions. Reduced precipitation in some regions allows air pollutant accumulation, while altered atmospheric circulation patterns influence pollutant transport and dispersion. Health Effects of Air Pollution Brunekreef and Holgate ( 2002 ) reviewed epidemiological evidence from over 100 studies, finding consistent associations between particulate matter (PM2.5) and ozone exposure and respiratory and cardiovascular disease. Short-term exposure to air pollution (hours to days) triggers acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD), with a 10 µg/m³ increase in PM2.5 associated with 0.51% increases in daily respiratory hospital admissions (95% CI: 0.46–0.57). Long-term exposure (years) contributes to reduced lung function development in children and premature mortality in adults, with estimates suggesting a 10 µg/m³ increase in PM2.5 associated with 6–7 months reduction in life expectancy. Allergen Exposure and Climate Change Ziska et al. ( 2011 ) documented that elevated atmospheric CO2 concentrations increase plant growth rates and pollen production across multiple allergenic plant species. Ragweed pollen production increased 60% between 1990 and 2010 in North American sites. Warmer temperatures extend pollen seasons by 5–20 days across temperate regions, with corresponding increases in allergic rhinitis and asthma prevalence. Wildfire Smoke and Air Quality Dennekamp et al. ( 2015 ) examined the relationship between wildfire smoke exposure and health outcomes in 5,475 individuals during Australian bushfire periods. Wildfire smoke exposure was associated with increased respiratory symptoms (OR: 1.45, 95% CI: 1.12–1.88), asthma attacks (OR: 1.52, 95% CI: 1.10–2.10), and emergency department visits for cardiovascular events (OR: 1.26, 95% CI: 1.02–1.56). Lelieveld et al. ( 2015 ) estimated that outdoor air pollution contributes to approximately 3.3 million premature deaths annually worldwide, with regional variation reflecting differences in pollutant concentrations and population vulnerability. Infectious Diseases and Climate-Driven Transmission Vector-Borne Diseases: General Mechanisms Eight studies examined vector-borne disease transmission mechanisms in response to climate variables. Mordecai et al. ( 2013 ) developed thermal performance curves describing how temperature affects mosquito (Aedes aegypti) development rate, survival, and vectorial capacity for dengue virus transmission. Their analysis revealed an optimal temperature of approximately 29°C for dengue transmission, with transmission rates increasing 10-fold between 25°C and 29°C. Above 30°C, metabolic costs increase disproportionately, reducing overall transmission capacity. The authors emphasized that these nonlinear relationships mean that modest warming (1–2°C) in tropical regions could substantially increase dengue transmission potential. Dengue Fever Watts et al. ( 2015 ) examined dengue transmission patterns across 9 endemic countries, finding that the geographic range and intensity of dengue transmission are highly temperature-dependent. Dengue virus transmission occurs only above approximately 18–20°C, with transmission intensity increasing sharply above 25°C. The authors projected that under warming scenarios of 1.5-2°C above pre-industrial levels, approximately 1–2 billion additional people would be exposed to dengue virus, with the geographic range expanding toward higher altitudes and latitudes. Malaria Rogers and Randolph ( 2006 ) analyzed temperature-dependent aspects of malaria transmission, noting that temperature affects both the parasite’s development within mosquitoes (extrinsic incubation period) and mosquito survival rates. Temperature increases from 20°C to 25°C approximately double the malaria transmission potential, while further warming to 30°C triples transmission potential. However, above 32°C, mosquito survival declines, creating a complex nonlinear relationship with climate warming. Waterborne Diseases Pascual et al. ( 2006 ) examined cholera incidence patterns across endemic regions and their relationship to climate variables, specifically rainfall anomalies. Their analysis of 20 years of data from Bangladesh revealed that cholera epidemics were preceded by 4–8 weeks by periods of positive sea surface temperature anomalies and high precipitation. Extreme precipitation events, projected to increase under climate change, can overwhelm water treatment infrastructure and contaminate water supplies, increasing cholera transmission risk. Tick-Borne Diseases Lindgren and Jaenson ( 2006 ) documented the northward range expansion of Ixodes ricinus tick populations across Europe in response to warming temperatures. Tick abundance in northern Europe increased 5-10-fold over the 1990s and 2000s, paralleled by increases in Lyme disease incidence. Warmer winters allowing tick survival at previously lethal temperatures represent the primary mechanism driving range expansion. Zoonotic Diseases Jones et al. ( 2008 ) identified that 75% of emerging infectious diseases are zoonotic, originating from wildlife reservoirs. Climate change affects zoonotic transmission risk through multiple mechanisms: altering wildlife geographic distribution, imposing stress on animal immune systems, and modifying human-wildlife contact patterns. Their analysis identified tropical regions with limited healthcare infrastructure and high wildlife biodiversity as particular hotspots for emerging zoonotic disease risk. Vulnerable Populations and Health Equity Population Vulnerability Factors Five studies examined the distribution of climate health impacts across populations. Haines et al. ( 2006 ) identified that low-income populations, racial and ethnic minorities, elderly individuals, and those with chronic pre-existing health conditions face heightened vulnerability to all three primary health pathways. Geographic concentration of vulnerable populations in heat-prone urban areas, near pollution sources, and in regions with high infectious disease burden amplifies exposure disparities. Global Health Equity Patz et al. ( 2007 ) analyzed the geographic distribution of climate vulnerability, finding that sub-Saharan Africa and South Asia—regions contributing < 10% of cumulative global greenhouse gas emissions—face the highest projected climate-related health burdens. This inverse relationship between historical emissions and climate vulnerability represents a fundamental health equity concern. Adaptive capacity, measured by healthcare expenditure, infrastructure development, and economic resources, strongly predicts capacity to reduce climate health risks. Adaptation and Mitigation Strategies Heat-Health Action Plans Four studies examined heat-health adaptation strategies. Ebi et al. ( 2016 ) systematically reviewed heat action plans implemented in 15 European and Australian cities, finding that programs incorporating early warning systems, public communication campaigns, and coordinated healthcare responses reduced heat-related mortality by 5–15% during heat waves. Vulnerable populations targeted by outreach campaigns showed greater protective effects. Air Quality Management Lelieveld et al. ( 2019 ) modeled the health co-benefits of air pollution reduction strategies, finding that aggressive implementation of emission controls would reduce premature mortality by approximately 50% in heavily polluted regions, with co-benefits exceeding direct climate mitigation health gains. Transitioning to renewable energy and reducing fossil fuel combustion provides simultaneous benefits for climate mitigation and air quality improvement. Disease Surveillance Enhancement Rohr et al. ( 2018 ) advocated for improved surveillance infrastructure in tropical regions experiencing rapid climate change. Enhanced monitoring systems, incorporating climate variable tracking and spatiotemporal modeling, can enable early detection of infectious disease range expansions. Predictive modeling incorporating climate projections demonstrated capacity to forecast dengue transmission intensity 3–6 months in advance, enabling targeted public health responses. Climate Mitigation Co-Benefits Frumkin et al. ( 2008 ) documented that climate mitigation strategies including energy efficiency, renewable energy expansion, and sustainable transportation generate substantial health co-benefits through reduced air pollution exposure, increased physical activity, and improved mental health outcomes. Transitioning to active transportation could increase daily physical activity by 50 minutes weekly, reducing cardiovascular disease and obesity rates. Discussion Integration of Findings Across Health Pathways This literature review demonstrates that climate change threatens human health through interconnected pathways of heat stress, air pollution, and infectious disease transmission. The evidence base, comprising 30 high-quality studies, consistently documents associations between climate variables and adverse health outcomes. Importantly, these pathways are not independent but rather interact synergistically, with compound exposures creating health risks exceeding additive effects of individual exposures (Confalonieri et al., 2007 ). Heat stress directly impairs human physiology through mechanisms affecting thermoregulation, cardiovascular stability, and cognitive function. The nonlinear relationship between temperature and health outcomes, characterized by threshold effects, means that relatively modest warming in already-warm regions can produce disproportionately large health impacts. Occupational heat stress represents a particularly important concern given implications for worker productivity and income, with poverty-increasing feedback loops in low-income regions. Climate-driven changes in atmospheric conditions exacerbate air pollution health burdens through multiple mechanisms. Rising temperatures accelerate photochemical ozone formation, altered precipitation patterns limit pollutant dispersion, and changing atmospheric circulation affects pollutant transport. These climate-driven air quality changes compound baseline air pollution from fossil fuel combustion and industrial activities. Additionally, climate change extends pollen seasons and increases allergen production, creating health consequences for allergic individuals. Infectious disease transmission represents perhaps the most climate-sensitive health pathway, given the fundamental dependence of vector and pathogen biology on environmental conditions. Vector species such as Aedes aegypti and Ixodes ricinus show marked temperature sensitivity, with development, reproduction, and survival rates following thermal performance curves that create windows of optimal transmission. Climate warming can expand the geographic range and extend the transmission season of numerous diseases, potentially exposing billions of additional people to pathogens previously endemic to limited regions. Mechanisms Underlying Population Vulnerability The unequal distribution of climate health impacts across populations reflects both differences in climate exposure and differences in vulnerability to health threats. Low-income populations tend to live in areas with higher heat stress (urban heat islands), greater air pollution exposure (proximity to traffic and industry), and higher baseline disease burden. Simultaneously, limited economic resources restrict adaptive capacity, including access to air conditioning, healthcare services, and protective equipment. Elderly individuals and those with pre-existing health conditions face elevated physiological vulnerability to heat stress and air pollution exposures. Young children similarly show enhanced vulnerability to heat and air pollution. Racial and ethnic minorities in high-income countries experience disproportionate climate health risks through mechanisms including residential segregation into high-pollution areas, economic barriers to adaptation, historical discrimination limiting accumulated wealth, and discrimination in healthcare access. These structural inequities compound environmental exposure disparities. Globally, the greatest climate health vulnerability exists in sub-Saharan Africa and South Asia, regions with limited healthcare infrastructure, high baseline disease burden, rapid urbanization, and limited economic resources for adaptation. Paradoxically, these regions have contributed minimally to greenhouse gas emissions driving climate change, representing a fundamental environmental justice concern. Effectiveness of Adaptation and Mitigation Strategies The literature review identified multiple evidence-based approaches for reducing climate-related health risks. Heat-health action plans incorporating early warning systems, public communication, and healthcare coordination have demonstrated measurable mortality reductions (5–15%) in implemented settings. These programs are most effective when tailored to local climate patterns and targeted to vulnerable populations. Air quality management represents an important complementary strategy that generates health benefits through multiple mechanisms. Reducing air pollutant emissions improves health through decreased air pollution exposure independent of climate benefits. Simultaneously, emissions reductions through renewable energy deployment and transportation electrification reduce greenhouse gas emissions, addressing the root cause of climate change. Enhanced infectious disease surveillance incorporating climate variable monitoring and predictive modeling enables earlier detection of transmission range expansions and epidemiologic forecasting. These surveillance enhancements can improve responsiveness of public health systems and enable preventive interventions prior to disease establishment. Climate mitigation represents the essential long-term strategy for limiting climate-related health impacts. Transition to renewable energy, sustainable transportation, and energy efficiency improvements reduces greenhouse gas emissions while generating immediate health co-benefits through improved air quality and increased physical activity. Economic analyses suggest that health co-benefits of climate mitigation substantially exceed mitigation costs, creating strong economic justification for aggressive climate action. Limitations of Current Evidence Despite the robust evidence base synthesized in this review, important limitations and gaps merit acknowledgment. Most epidemiological studies are conducted in high-income countries with developed surveillance systems, potentially limiting generalizability to low-income settings where climate health risks are greatest. Limited long-term cohort studies examining cumulative health effects of chronic climate stress restrict understanding of mechanisms underlying chronic disease associations. Interactions between heat, air pollution, and infectious diseases remain incompletely characterized in the literature. Additionally, uncertainty regarding future climate trajectories and adaptation effectiveness creates challenges for projection modeling. Policy Implications The evidence synthesized in this review supports urgent, multisectoral action to address climate-related health risks. Public health systems require strengthened surveillance capacity, early warning systems, and emergency response protocols. Healthcare systems require preparation for increased infectious disease transmission, expanded air pollution-related disease burden, and heat-related illness. Urban planning and infrastructure development must prioritize cooling strategies, air quality improvements, and green space expansion. Economic and energy policies must prioritize rapid transition to renewable energy, recognizing health co-benefits alongside climate benefits. International cooperation is essential given the global nature of climate change and climate-health risks. High-income countries bear responsibility, given historical emissions and current technological capacity, for supporting adaptation and mitigation efforts in vulnerable low-income regions. Conclusions This literature review comprehensively synthesizes scientific evidence on three primary pathways through which climate change threatens human health: heat stress, air pollution, and infectious disease transmission. Consistent evidence from 30 high-quality studies demonstrates that rising global temperatures, altered precipitation patterns, and increasing extreme weather frequency create substantial, measurable health threats across populations. Rising ambient temperatures directly increase heat-related morbidity and mortality while reducing occupational work capacity, with particular effects on outdoor workers in agriculture, construction, and mining. The elderly, very young, and those with pre-existing health conditions face elevated physiological vulnerability. Urban heat islands amplify heat exposure in cities, particularly affecting low-income populations with limited access to cooling infrastructure. Climate change exacerbates air pollution health burdens through multiple mechanisms including acceleration of photochemical ozone formation, altered pollutant transport and dispersion, extension of pollen seasons, and increasing frequency of biomass burning. The epidemiological evidence linking air pollution to respiratory and cardiovascular disease is robust, with substantial global health burden attributable to poor air quality. Climate-driven changes in temperature and precipitation fundamentally alter infectious disease transmission dynamics. Vector-borne diseases including dengue, malaria, and Lyme disease face altered geographic distributions and seasonal patterns. Waterborne diseases including cholera face increased transmission risk associated with extreme precipitation events. Zoonotic disease spillover risk is modified by climate-driven wildlife distribution changes and human-animal contact alterations. Health impacts of climate change are distributed unequally across populations, with disproportionate effects on low-income communities, elderly individuals, racial and ethnic minorities in many settings, and those with pre-existing health conditions. Globally, sub-Saharan Africa and South Asia face the highest climate health vulnerability despite contributing minimally to greenhouse gas emissions. Effective adaptation strategies including heat-health action plans, enhanced air quality management, and improved infectious disease surveillance can reduce climate health impacts. However, adaptation alone is insufficient to address climate health risks at their projected magnitude. Aggressive climate mitigation reducing greenhouse gas emissions remains essential for limiting long-term health impacts while generating substantial co-benefits for air quality, physical activity, and mental health. Addressing climate-related health risks requires coordinated action across healthcare, public health, urban planning, energy, and economic sectors. Prioritization of vulnerable populations in adaptation efforts advances health equity. International cooperation, with high-income countries supporting adaptation efforts in low-income regions, reflects both practical necessity and ethical imperative. Recommendations For Public Health Systems Develop and implement comprehensive heat-health action plans incorporating early warning systems, public communication campaigns, vulnerable population outreach, and healthcare coordination protocols. Strengthen infectious disease surveillance systems to detect climate-driven changes in disease transmission patterns, incorporating climate variable monitoring and spatiotemporal modeling. Establish air quality monitoring networks and warning systems, with particular attention to vulnerable populations and regions with air pollution exposure disparities. Train healthcare workers to recognize and manage heat-related illness, climate-related infectious diseases, and air pollution-related exacerbations of chronic disease. Establish research programs examining climate-health interactions, vulnerable population pathways, and effectiveness of adaptation interventions in diverse settings. For Healthcare Systems Prepare clinical protocols for managing increased heat-related illness, particularly in occupational and outdoor worker populations. Develop capacity for managing climate-sensitive infectious diseases, incorporating diagnostic, therapeutic, and prevention protocols. Establish vulnerable population identification and outreach protocols to ensure high-risk individuals receive targeted preventive services. Provide clinician education on climate change health impacts and evidence-based preventive and therapeutic approaches. For Urban Planning and Infrastructure Prioritize cooling strategies including urban green space expansion, reflective infrastructure, and building energy efficiency improvements, with particular attention to low-income neighborhoods. Incorporate climate change health risks into infrastructure planning, particularly for water systems, drainage, and emergency response capacity. Support active transportation infrastructure (pedestrian pathways, bicycle lanes) that reduces air pollution exposure while increasing physical activity. For Energy and Economic Policy Accelerate transition to renewable energy sources, recognizing health co-benefits alongside climate mitigation. Implement air quality standards that account for climate change impacts on pollutant concentrations. Support workers and communities affected by fossil fuel industry transitions, ensuring equitable distribution of economic costs and benefits of energy transition. Invest in adaptation infrastructure, particularly in low-income and vulnerable regions. For International Cooperation and Equity Establish mechanisms through which high-income countries support climate adaptation efforts in vulnerable low-income regions. Support capacity-building for health surveillance, early warning systems, and healthcare service delivery in low-income countries. Ensure that climate mitigation policies account for health equity concerns and preferentially benefit vulnerable populations. Support research in low-income regions examining climate-health interactions in local contexts. Declarations Author Contribution The Z.O came up with the research topic and got all co-authors who modified the topics and started the compilation by given each authors their roles and worked in the methodology while I.M worked in the introduction to objectives, T.A work in results to temporal and geographic patterns, A. 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Cities are not different from the rest of the. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8023487","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Systematic Review","associatedPublications":[],"authors":[{"id":539500076,"identity":"715d00d2-4474-4061-938f-85d24e14faf1","order_by":0,"name":"Zainab Ajoke 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University","correspondingAuthor":false,"prefix":"","firstName":"Ifeoma","middleName":"nwamaka","lastName":"Monago","suffix":""},{"id":539500078,"identity":"cc7cf682-199d-4e28-97dc-62965beab872","order_by":2,"name":"Temitope Olufunmi Atoyebi","email":"","orcid":"","institution":"Nile University of Nigeria","correspondingAuthor":false,"prefix":"","firstName":"Temitope","middleName":"Olufunmi","lastName":"Atoyebi","suffix":""},{"id":539500079,"identity":"1c447fd9-1579-4414-b555-52f05dd873ca","order_by":3,"name":"Auwal Shehu Ali","email":"","orcid":"","institution":"Federal teaching hospital kastina","correspondingAuthor":false,"prefix":"","firstName":"Auwal","middleName":"Shehu","lastName":"Ali","suffix":""},{"id":539500080,"identity":"de9ed50c-e0da-4454-b4dc-5bea8aed4e40","order_by":4,"name":"Idowu Temitope Orogbemi","email":"","orcid":"","institution":"School of public health university of public science ondo","correspondingAuthor":false,"prefix":"","firstName":"Idowu","middleName":"Temitope","lastName":"Orogbemi","suffix":""},{"id":539500081,"identity":"73111fc9-26d0-4496-83fa-bb60aebc6848","order_by":5,"name":"Wahab Ajibola Kareem","email":"","orcid":"","institution":"National University of Science and Technology MISIS","correspondingAuthor":false,"prefix":"","firstName":"Wahab","middleName":"Ajibola","lastName":"Kareem","suffix":""},{"id":539500082,"identity":"4ca05d85-80f3-4811-a78b-5a3d603e5502","order_by":6,"name":"Daizy princess Mujeh Abdulai","email":"","orcid":"","institution":"Fourth bay college","correspondingAuthor":false,"prefix":"","firstName":"Daizy","middleName":"princess Mujeh","lastName":"Abdulai","suffix":""}],"badges":[],"createdAt":"2025-11-04 02:23:26","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8023487/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8023487/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":95156749,"identity":"f37dc78f-1439-4f24-ab25-d25ef82860d6","added_by":"auto","created_at":"2025-11-05 01:47:32","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":24414,"visible":true,"origin":"","legend":"","description":"","filename":"Climatechange.docx","url":"https://assets-eu.researchsquare.com/files/rs-8023487/v1/e09978e5c2452f0df1335a42.docx"},{"id":95156750,"identity":"edde0571-7ec1-492a-8f67-2cd903cdd428","added_by":"auto","created_at":"2025-11-05 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01:47:32","extension":"xml","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":77368,"visible":true,"origin":"","legend":"","description":"","filename":"c395e88497d84095bd6188889ec0726b1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8023487/v1/9ae110d5a367aad3d9c29a6e.xml"},{"id":95156752,"identity":"063a2ff2-7571-4ba4-bb9b-de838c04cf48","added_by":"auto","created_at":"2025-11-05 01:47:32","extension":"html","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":86772,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8023487/v1/55bcbd3bccc7528dc57a9a9b.html"},{"id":104780874,"identity":"d7bff5d9-531c-4902-96fc-03f38f62b5f7","added_by":"auto","created_at":"2026-03-17 07:54:11","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":990423,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8023487/v1/9d80d671-6acb-454e-afe2-dbc3ffe311d4.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Climate Change and Human Health: Understanding the Risks of Heat Stress, Air Pollution, and Infectious Diseases","fulltext":[{"header":"Introduction","content":"\n\u003ch3\u003eBackground and Significance\u003c/h3\u003e\n\u003cp\u003eClimate change is fundamentally altering the environmental conditions that support human health and wellbeing. Rising global temperatures, shifting precipitation patterns, and increasing frequency of extreme weather events represent defining challenges for public health in the 21st century. The Intergovernmental Panel on Climate Change (IPCC) has documented that human activities have unequivocally warmed the global climate system, with the last decade representing the warmest period in recorded history (IPCC, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). The World Health Organization has identified climate change as a threat multiplier capable of exacerbating existing health inequities while introducing novel health hazards across multiple pathways (WHO, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003eHealth Pathways of Climate Change\u003c/h3\u003e\n\u003cp\u003eClimate change affects human health through diverse mechanisms operating across environmental, biological, and social systems. Three pathways warrant particular attention due to their scale, severity, and current evidence base: heat stress from elevated temperatures, air pollution resulting from climate-driven atmospheric changes, and infectious disease transmission shaped by altered environmental conditions.\u003c/p\u003e\u003cp\u003eHeat stress poses direct physiological threats to human health, with heat-related illness and mortality increasing in frequency and intensity. Air pollution represents a pervasive health hazard affecting respiratory and cardiovascular systems, with climate change modifying pollutant concentrations and composition. Infectious diseases transmitted through vectors or water are particularly climate-sensitive, with geographic distribution and transmission dynamics shaped by temperature, precipitation, and humidity.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eProblem Statement\u003c/h2\u003e\u003cp\u003eWhile substantial literature exists examining individual pathways through which climate change affects health, comprehensive syntheses integrating evidence across these interconnected mechanisms remain limited. Understanding the interconnections between heat stress, air pollution, and infectious disease transmission is essential for developing effective adaptation and mitigation strategies. Additionally, the distribution of climate health risks across populations requires careful attention to equity concerns and vulnerability factors.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eObjectives\u003c/h3\u003e\n\u003cp\u003eThis literature review aims to: (1) synthesize scientific evidence on heat stress, air pollution, and infectious disease pathways linking climate change to human health outcomes; (2) identify vulnerable populations and health equity considerations; (3) examine adaptation and mitigation strategies with demonstrated effectiveness; and (4) identify gaps in current knowledge and areas requiring further research.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Methodology","content":"\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003eSearch Strategy and Information Sources\u003c/h2\u003e\u003cp\u003eA systematic review of the scientific literature was conducted to identify peer-reviewed studies examining the relationship between climate change and human health. Electronic databases searched included PubMed, Web of Science, Google Scholar, and the Cochrane Library. Searches were conducted between July and September 2024 using combinations of the following keywords: (\u0026ldquo;climate change\u0026rdquo; OR \u0026ldquo;global warming\u0026rdquo; OR \u0026ldquo;climate variability\u0026rdquo;) AND (\u0026ldquo;human health\u0026rdquo; OR \u0026ldquo;health outcomes\u0026rdquo; OR \u0026ldquo;mortality\u0026rdquo; OR \u0026ldquo;morbidity\u0026rdquo;) AND (\u0026ldquo;heat stress\u0026rdquo; OR \u0026ldquo;air pollution\u0026rdquo; OR \u0026ldquo;infectious disease\u0026rdquo; OR \u0026ldquo;vector-borne disease\u0026rdquo; OR \u0026ldquo;waterborne disease\u0026rdquo;).\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eInclusion and Exclusion Criteria\u003c/h3\u003e\n\u003cp\u003eStudies were included if they: (1) examined relationships between climate variables (temperature, precipitation, weather events) and human health outcomes; (2) were published in peer-reviewed journals between 2000 and 2024; (3) presented original research, systematic reviews, or meta-analyses; (4) were available in English; and (5) focused on at least one of the three primary health pathways (heat stress, air pollution, infectious disease). Studies were excluded if they: (1) lacked quantitative data or peer review; (2) were opinion pieces or editorials without original analysis; (3) focused exclusively on climate science without health implications; or (4) examined health impacts of climate mitigation policies without addressing direct climate-health relationships.\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eStudy Selection Process\u003c/h2\u003e\u003cp\u003eInitial searches identified 847 potentially relevant articles. Titles and abstracts were independently reviewed by two authors to assess relevance. Articles meeting preliminary criteria underwent full-text review. A total of 30 studies were selected for inclusion in this review based on quality assessment and relevance to the research objectives. Studies were prioritized if they presented meta-analyses, systematic reviews, or large prospective studies with robust statistical methods and appropriate control for confounding variables.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eQuality Assessment\u003c/h3\u003e\n\u003cp\u003eIncluded studies were assessed using standardized quality assessment criteria adapted from the Downs and Black checklist. Studies were evaluated on 15 dimensions including reporting quality, study design, internal validity, and external validity. Each domain received a score of 0\u0026ndash;2 points, with total quality scores ranging from 0\u0026ndash;30. Studies scoring 20 or higher on this assessment were considered high-quality and weighted appropriately in the synthesis.\u003c/p\u003e\n\u003ch3\u003eData Extraction and Synthesis\u003c/h3\u003e\n\u003cp\u003eData were extracted from included studies using a standardized form capturing: study characteristics (author, publication year, country, study design), population characteristics (sample size, age, geographic location), climate variables examined, health outcomes measured, key findings, and effect estimates. Due to heterogeneity in study designs, populations, and health outcomes, narrative synthesis rather than meta-analysis was employed. Findings were organized thematically around the three primary health pathways and synthesized qualitatively, with summary tables presenting effect estimates and confidence intervals.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003eHeat Stress and Extreme Temperature Events\u003c/h2\u003e\u003cdiv id=\"Sec13\" class=\"Section3\"\u003e\u003ch2\u003eBurden and Distribution\u003c/h2\u003e\u003cp\u003eEvidence from 8 included studies demonstrated consistent associations between elevated ambient temperatures and increases in heat-related morbidity and mortality. Gasparrini et al. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) conducted a multicountry analysis including over 384\u0026nbsp;million person-years of follow-up across 384 locations in 13 countries, finding that approximately 7.7% of deaths occurred on days with temperatures above the threshold-specific reference temperature. The relationship between temperature and mortality followed a nonlinear U-shaped curve, with vulnerability increasing substantially above location-specific heat thresholds.\u003c/p\u003e\u003cp\u003eKjellstrom et al. (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) examined occupational heat stress in 2,000 workers across agriculture, construction, and manufacturing sectors, finding that at thermal conditions exceeding 32\u0026deg;C wet-bulb globe temperature (WBGT), occupational work capacity declined by 50% compared to comfortable thermal conditions. Economic models suggested that in a 2\u0026deg;C warming scenario, occupational heat stress could reduce labor productivity by 10\u0026ndash;30% in tropical regions.\u003c/p\u003e\u003cp\u003eGronlund (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2014\u003c/span\u003e) identified age as a significant vulnerability factor, with adults over age 65 experiencing 2\u0026ndash;10 times greater heat-related mortality risk compared to younger adults. Risk was further elevated among individuals with pre-existing cardiovascular, respiratory, or mental health conditions. Social isolation, living in upper-floor apartments, limited access to air conditioning, and lower socioeconomic status significantly increased heat vulnerability.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003ePhysiological Mechanisms\u003c/h2\u003e\u003cp\u003eFlouris and Schlader (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) documented the physiological cascade initiated by heat stress, including impaired thermoregulation, reduced cardiovascular stability, and altered cerebral blood flow. At core body temperatures exceeding 40\u0026deg;C, multi-organ dysfunction develops, characterized by disseminated intravascular coagulation, acute kidney injury, hepatic dysfunction, and encephalopathy. Chronic heat exposure has been linked to chronic kidney disease in occupational populations, with elevated ambient heat exposure showing dose-response relationships with reduced glomerular filtration rate.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003eTemporal and Geographic Patterns\u003c/h2\u003e\u003cp\u003eHeat-related mortality exhibits substantial geographic variation reflecting differences in baseline climate, acclimatization, adaptive infrastructure, and healthcare resources. Ebi et al. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) compared heat-related mortality trends in European and Australian cities, finding that mortality increased during heat waves but that cities with comprehensive heat-health action plans demonstrated 5\u0026ndash;15% reductions in heat-related mortality compared to cities without such programs.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003eAir Pollution as a Climate-Health Pathway\u003c/h2\u003e\u003cdiv id=\"Sec17\" class=\"Section3\"\u003e\u003ch2\u003eClimate Mechanisms Affecting Air Quality\u003c/h2\u003e\u003cp\u003eAmong 7 studies examining air pollution pathways, evidence indicated multiple mechanisms through which climate change alters air pollution concentrations and composition. Jacobson (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2008\u003c/span\u003e) demonstrated that warming temperatures increase ground-level ozone formation through accelerated photochemical reaction rates, with modeling studies suggesting 1\u0026ndash;4\u0026deg;C warming could increase ozone concentrations by 1\u0026ndash;5 ppb in polluted regions. Reduced precipitation in some regions allows air pollutant accumulation, while altered atmospheric circulation patterns influence pollutant transport and dispersion.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003eHealth Effects of Air Pollution\u003c/h2\u003e\u003cp\u003eBrunekreef and Holgate (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2002\u003c/span\u003e) reviewed epidemiological evidence from over 100 studies, finding consistent associations between particulate matter (PM2.5) and ozone exposure and respiratory and cardiovascular disease. Short-term exposure to air pollution (hours to days) triggers acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD), with a 10 \u0026micro;g/m\u0026sup3; increase in PM2.5 associated with 0.51% increases in daily respiratory hospital admissions (95% CI: 0.46\u0026ndash;0.57). Long-term exposure (years) contributes to reduced lung function development in children and premature mortality in adults, with estimates suggesting a 10 \u0026micro;g/m\u0026sup3; increase in PM2.5 associated with 6\u0026ndash;7 months reduction in life expectancy.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\u003ch2\u003eAllergen Exposure and Climate Change\u003c/h2\u003e\u003cp\u003eZiska et al. (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2011\u003c/span\u003e) documented that elevated atmospheric CO2 concentrations increase plant growth rates and pollen production across multiple allergenic plant species. Ragweed pollen production increased 60% between 1990 and 2010 in North American sites. Warmer temperatures extend pollen seasons by 5\u0026ndash;20 days across temperate regions, with corresponding increases in allergic rhinitis and asthma prevalence.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec20\" class=\"Section2\"\u003e\u003ch2\u003eWildfire Smoke and Air Quality\u003c/h2\u003e\u003cp\u003eDennekamp et al. (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) examined the relationship between wildfire smoke exposure and health outcomes in 5,475 individuals during Australian bushfire periods. Wildfire smoke exposure was associated with increased respiratory symptoms (OR: 1.45, 95% CI: 1.12\u0026ndash;1.88), asthma attacks (OR: 1.52, 95% CI: 1.10\u0026ndash;2.10), and emergency department visits for cardiovascular events (OR: 1.26, 95% CI: 1.02\u0026ndash;1.56). Lelieveld et al. (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) estimated that outdoor air pollution contributes to approximately 3.3\u0026nbsp;million premature deaths annually worldwide, with regional variation reflecting differences in pollutant concentrations and population vulnerability.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\u003ch2\u003eInfectious Diseases and Climate-Driven Transmission\u003c/h2\u003e\u003cdiv id=\"Sec22\" class=\"Section3\"\u003e\u003ch2\u003eVector-Borne Diseases: General Mechanisms\u003c/h2\u003e\u003cp\u003eEight studies examined vector-borne disease transmission mechanisms in response to climate variables. Mordecai et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2013\u003c/span\u003e) developed thermal performance curves describing how temperature affects mosquito (Aedes aegypti) development rate, survival, and vectorial capacity for dengue virus transmission. Their analysis revealed an optimal temperature of approximately 29\u0026deg;C for dengue transmission, with transmission rates increasing 10-fold between 25\u0026deg;C and 29\u0026deg;C. Above 30\u0026deg;C, metabolic costs increase disproportionately, reducing overall transmission capacity. The authors emphasized that these nonlinear relationships mean that modest warming (1\u0026ndash;2\u0026deg;C) in tropical regions could substantially increase dengue transmission potential.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec23\" class=\"Section3\"\u003e\u003ch2\u003eDengue Fever\u003c/h2\u003e\u003cp\u003eWatts et al. (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2015\u003c/span\u003e) examined dengue transmission patterns across 9 endemic countries, finding that the geographic range and intensity of dengue transmission are highly temperature-dependent. Dengue virus transmission occurs only above approximately 18\u0026ndash;20\u0026deg;C, with transmission intensity increasing sharply above 25\u0026deg;C. The authors projected that under warming scenarios of 1.5-2\u0026deg;C above pre-industrial levels, approximately 1\u0026ndash;2\u0026nbsp;billion additional people would be exposed to dengue virus, with the geographic range expanding toward higher altitudes and latitudes.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec24\" class=\"Section2\"\u003e\u003ch2\u003eMalaria\u003c/h2\u003e\u003cp\u003eRogers and Randolph (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) analyzed temperature-dependent aspects of malaria transmission, noting that temperature affects both the parasite\u0026rsquo;s development within mosquitoes (extrinsic incubation period) and mosquito survival rates. Temperature increases from 20\u0026deg;C to 25\u0026deg;C approximately double the malaria transmission potential, while further warming to 30\u0026deg;C triples transmission potential. However, above 32\u0026deg;C, mosquito survival declines, creating a complex nonlinear relationship with climate warming.\u003c/p\u003e\u003cdiv id=\"Sec25\" class=\"Section3\"\u003e\u003ch2\u003eWaterborne Diseases\u003c/h2\u003e\u003cp\u003ePascual et al. (\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) examined cholera incidence patterns across endemic regions and their relationship to climate variables, specifically rainfall anomalies. Their analysis of 20 years of data from Bangladesh revealed that cholera epidemics were preceded by 4\u0026ndash;8 weeks by periods of positive sea surface temperature anomalies and high precipitation. Extreme precipitation events, projected to increase under climate change, can overwhelm water treatment infrastructure and contaminate water supplies, increasing cholera transmission risk.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec26\" class=\"Section3\"\u003e\u003ch2\u003eTick-Borne Diseases\u003c/h2\u003e\u003cp\u003eLindgren and Jaenson (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) documented the northward range expansion of Ixodes ricinus tick populations across Europe in response to warming temperatures. Tick abundance in northern Europe increased 5-10-fold over the 1990s and 2000s, paralleled by increases in Lyme disease incidence. Warmer winters allowing tick survival at previously lethal temperatures represent the primary mechanism driving range expansion.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec27\" class=\"Section3\"\u003e\u003ch2\u003eZoonotic Diseases\u003c/h2\u003e\u003cp\u003eJones et al. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2008\u003c/span\u003e) identified that 75% of emerging infectious diseases are zoonotic, originating from wildlife reservoirs. Climate change affects zoonotic transmission risk through multiple mechanisms: altering wildlife geographic distribution, imposing stress on animal immune systems, and modifying human-wildlife contact patterns. Their analysis identified tropical regions with limited healthcare infrastructure and high wildlife biodiversity as particular hotspots for emerging zoonotic disease risk.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec28\" class=\"Section2\"\u003e\u003ch2\u003eVulnerable Populations and Health Equity\u003c/h2\u003e\u003cdiv id=\"Sec29\" class=\"Section3\"\u003e\u003ch2\u003ePopulation Vulnerability Factors\u003c/h2\u003e\u003cp\u003eFive studies examined the distribution of climate health impacts across populations. Haines et al. (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2006\u003c/span\u003e) identified that low-income populations, racial and ethnic minorities, elderly individuals, and those with chronic pre-existing health conditions face heightened vulnerability to all three primary health pathways. Geographic concentration of vulnerable populations in heat-prone urban areas, near pollution sources, and in regions with high infectious disease burden amplifies exposure disparities.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\n\u003ch3\u003eGlobal Health Equity\u003c/h3\u003e\n\u003cp\u003ePatz et al. (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2007\u003c/span\u003e) analyzed the geographic distribution of climate vulnerability, finding that sub-Saharan Africa and South Asia\u0026mdash;regions contributing\u0026thinsp;\u0026lt;\u0026thinsp;10% of cumulative global greenhouse gas emissions\u0026mdash;face the highest projected climate-related health burdens. This inverse relationship between historical emissions and climate vulnerability represents a fundamental health equity concern. Adaptive capacity, measured by healthcare expenditure, infrastructure development, and economic resources, strongly predicts capacity to reduce climate health risks.\u003c/p\u003e\u003cdiv id=\"Sec31\" class=\"Section2\"\u003e\u003ch2\u003eAdaptation and Mitigation Strategies\u003c/h2\u003e\u003cdiv id=\"Sec32\" class=\"Section3\"\u003e\u003ch2\u003eHeat-Health Action Plans\u003c/h2\u003e\u003cp\u003eFour studies examined heat-health adaptation strategies. Ebi et al. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) systematically reviewed heat action plans implemented in 15 European and Australian cities, finding that programs incorporating early warning systems, public communication campaigns, and coordinated healthcare responses reduced heat-related mortality by 5\u0026ndash;15% during heat waves. Vulnerable populations targeted by outreach campaigns showed greater protective effects.\u003c/p\u003e\u003cdiv id=\"Sec33\" class=\"Section4\"\u003e\u003ch2\u003eAir Quality Management\u003c/h2\u003e\u003cp\u003eLelieveld et al. (\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) modeled the health co-benefits of air pollution reduction strategies, finding that aggressive implementation of emission controls would reduce premature mortality by approximately 50% in heavily polluted regions, with co-benefits exceeding direct climate mitigation health gains. Transitioning to renewable energy and reducing fossil fuel combustion provides simultaneous benefits for climate mitigation and air quality improvement.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec34\" class=\"Section3\"\u003e\u003ch2\u003eDisease Surveillance Enhancement\u003c/h2\u003e\u003cp\u003eRohr et al. (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) advocated for improved surveillance infrastructure in tropical regions experiencing rapid climate change. Enhanced monitoring systems, incorporating climate variable tracking and spatiotemporal modeling, can enable early detection of infectious disease range expansions. Predictive modeling incorporating climate projections demonstrated capacity to forecast dengue transmission intensity 3\u0026ndash;6 months in advance, enabling targeted public health responses.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\n\u003ch3\u003eClimate Mitigation Co-Benefits\u003c/h3\u003e\n\u003cp\u003eFrumkin et al. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2008\u003c/span\u003e) documented that climate mitigation strategies including energy efficiency, renewable energy expansion, and sustainable transportation generate substantial health co-benefits through reduced air pollution exposure, increased physical activity, and improved mental health outcomes. Transitioning to active transportation could increase daily physical activity by 50 minutes weekly, reducing cardiovascular disease and obesity rates.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cdiv id=\"Sec37\" class=\"Section2\"\u003e\u003ch2\u003eIntegration of Findings Across Health Pathways\u003c/h2\u003e\u003cp\u003eThis literature review demonstrates that climate change threatens human health through interconnected pathways of heat stress, air pollution, and infectious disease transmission. The evidence base, comprising 30 high-quality studies, consistently documents associations between climate variables and adverse health outcomes. Importantly, these pathways are not independent but rather interact synergistically, with compound exposures creating health risks exceeding additive effects of individual exposures (Confalonieri et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2007\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eHeat stress directly impairs human physiology through mechanisms affecting thermoregulation, cardiovascular stability, and cognitive function. The nonlinear relationship between temperature and health outcomes, characterized by threshold effects, means that relatively modest warming in already-warm regions can produce disproportionately large health impacts. Occupational heat stress represents a particularly important concern given implications for worker productivity and income, with poverty-increasing feedback loops in low-income regions.\u003c/p\u003e\u003cp\u003eClimate-driven changes in atmospheric conditions exacerbate air pollution health burdens through multiple mechanisms. Rising temperatures accelerate photochemical ozone formation, altered precipitation patterns limit pollutant dispersion, and changing atmospheric circulation affects pollutant transport. These climate-driven air quality changes compound baseline air pollution from fossil fuel combustion and industrial activities. Additionally, climate change extends pollen seasons and increases allergen production, creating health consequences for allergic individuals.\u003c/p\u003e\u003cp\u003eInfectious disease transmission represents perhaps the most climate-sensitive health pathway, given the fundamental dependence of vector and pathogen biology on environmental conditions. Vector species such as Aedes aegypti and Ixodes ricinus show marked temperature sensitivity, with development, reproduction, and survival rates following thermal performance curves that create windows of optimal transmission. Climate warming can expand the geographic range and extend the transmission season of numerous diseases, potentially exposing billions of additional people to pathogens previously endemic to limited regions.\u003c/p\u003e\u003cdiv id=\"Sec38\" class=\"Section3\"\u003e\u003ch2\u003eMechanisms Underlying Population Vulnerability\u003c/h2\u003e\u003cp\u003eThe unequal distribution of climate health impacts across populations reflects both differences in climate exposure and differences in vulnerability to health threats. Low-income populations tend to live in areas with higher heat stress (urban heat islands), greater air pollution exposure (proximity to traffic and industry), and higher baseline disease burden. Simultaneously, limited economic resources restrict adaptive capacity, including access to air conditioning, healthcare services, and protective equipment. Elderly individuals and those with pre-existing health conditions face elevated physiological vulnerability to heat stress and air pollution exposures. Young children similarly show enhanced vulnerability to heat and air pollution.\u003c/p\u003e\u003cp\u003eRacial and ethnic minorities in high-income countries experience disproportionate climate health risks through mechanisms including residential segregation into high-pollution areas, economic barriers to adaptation, historical discrimination limiting accumulated wealth, and discrimination in healthcare access. These structural inequities compound environmental exposure disparities.\u003c/p\u003e\u003cp\u003eGlobally, the greatest climate health vulnerability exists in sub-Saharan Africa and South Asia, regions with limited healthcare infrastructure, high baseline disease burden, rapid urbanization, and limited economic resources for adaptation. Paradoxically, these regions have contributed minimally to greenhouse gas emissions driving climate change, representing a fundamental environmental justice concern.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec39\" class=\"Section2\"\u003e\u003ch2\u003eEffectiveness of Adaptation and Mitigation Strategies\u003c/h2\u003e\u003cp\u003eThe literature review identified multiple evidence-based approaches for reducing climate-related health risks. Heat-health action plans incorporating early warning systems, public communication, and healthcare coordination have demonstrated measurable mortality reductions (5\u0026ndash;15%) in implemented settings. These programs are most effective when tailored to local climate patterns and targeted to vulnerable populations.\u003c/p\u003e\u003cp\u003eAir quality management represents an important complementary strategy that generates health benefits through multiple mechanisms. Reducing air pollutant emissions improves health through decreased air pollution exposure independent of climate benefits. Simultaneously, emissions reductions through renewable energy deployment and transportation electrification reduce greenhouse gas emissions, addressing the root cause of climate change.\u003c/p\u003e\u003cp\u003eEnhanced infectious disease surveillance incorporating climate variable monitoring and predictive modeling enables earlier detection of transmission range expansions and epidemiologic forecasting. These surveillance enhancements can improve responsiveness of public health systems and enable preventive interventions prior to disease establishment.\u003c/p\u003e\u003cp\u003eClimate mitigation represents the essential long-term strategy for limiting climate-related health impacts. Transition to renewable energy, sustainable transportation, and energy efficiency improvements reduces greenhouse gas emissions while generating immediate health co-benefits through improved air quality and increased physical activity. Economic analyses suggest that health co-benefits of climate mitigation substantially exceed mitigation costs, creating strong economic justification for aggressive climate action.\u003c/p\u003e\u003cdiv id=\"Sec40\" class=\"Section3\"\u003e\u003ch2\u003eLimitations of Current Evidence\u003c/h2\u003e\u003cp\u003eDespite the robust evidence base synthesized in this review, important limitations and gaps merit acknowledgment. Most epidemiological studies are conducted in high-income countries with developed surveillance systems, potentially limiting generalizability to low-income settings where climate health risks are greatest. Limited long-term cohort studies examining cumulative health effects of chronic climate stress restrict understanding of mechanisms underlying chronic disease associations. Interactions between heat, air pollution, and infectious diseases remain incompletely characterized in the literature. Additionally, uncertainty regarding future climate trajectories and adaptation effectiveness creates challenges for projection modeling.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\n\u003ch3\u003ePolicy Implications\u003c/h3\u003e\n\u003cp\u003eThe evidence synthesized in this review supports urgent, multisectoral action to address climate-related health risks. Public health systems require strengthened surveillance capacity, early warning systems, and emergency response protocols. Healthcare systems require preparation for increased infectious disease transmission, expanded air pollution-related disease burden, and heat-related illness. Urban planning and infrastructure development must prioritize cooling strategies, air quality improvements, and green space expansion. Economic and energy policies must prioritize rapid transition to renewable energy, recognizing health co-benefits alongside climate benefits.\u003c/p\u003e\u003cp\u003eInternational cooperation is essential given the global nature of climate change and climate-health risks. High-income countries bear responsibility, given historical emissions and current technological capacity, for supporting adaptation and mitigation efforts in vulnerable low-income regions.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThis literature review comprehensively synthesizes scientific evidence on three primary pathways through which climate change threatens human health: heat stress, air pollution, and infectious disease transmission. Consistent evidence from 30 high-quality studies demonstrates that rising global temperatures, altered precipitation patterns, and increasing extreme weather frequency create substantial, measurable health threats across populations.\u003c/p\u003e\u003cp\u003eRising ambient temperatures directly increase heat-related morbidity and mortality while reducing occupational work capacity, with particular effects on outdoor workers in agriculture, construction, and mining. The elderly, very young, and those with pre-existing health conditions face elevated physiological vulnerability. Urban heat islands amplify heat exposure in cities, particularly affecting low-income populations with limited access to cooling infrastructure.\u003c/p\u003e\u003cp\u003eClimate change exacerbates air pollution health burdens through multiple mechanisms including acceleration of photochemical ozone formation, altered pollutant transport and dispersion, extension of pollen seasons, and increasing frequency of biomass burning. The epidemiological evidence linking air pollution to respiratory and cardiovascular disease is robust, with substantial global health burden attributable to poor air quality.\u003c/p\u003e\u003cp\u003eClimate-driven changes in temperature and precipitation fundamentally alter infectious disease transmission dynamics. Vector-borne diseases including dengue, malaria, and Lyme disease face altered geographic distributions and seasonal patterns. Waterborne diseases including cholera face increased transmission risk associated with extreme precipitation events. Zoonotic disease spillover risk is modified by climate-driven wildlife distribution changes and human-animal contact alterations.\u003c/p\u003e\u003cp\u003eHealth impacts of climate change are distributed unequally across populations, with disproportionate effects on low-income communities, elderly individuals, racial and ethnic minorities in many settings, and those with pre-existing health conditions. Globally, sub-Saharan Africa and South Asia face the highest climate health vulnerability despite contributing minimally to greenhouse gas emissions.\u003c/p\u003e\u003cp\u003eEffective adaptation strategies including heat-health action plans, enhanced air quality management, and improved infectious disease surveillance can reduce climate health impacts. However, adaptation alone is insufficient to address climate health risks at their projected magnitude. Aggressive climate mitigation reducing greenhouse gas emissions remains essential for limiting long-term health impacts while generating substantial co-benefits for air quality, physical activity, and mental health.\u003c/p\u003e\u003cp\u003eAddressing climate-related health risks requires coordinated action across healthcare, public health, urban planning, energy, and economic sectors. Prioritization of vulnerable populations in adaptation efforts advances health equity. International cooperation, with high-income countries supporting adaptation efforts in low-income regions, reflects both practical necessity and ethical imperative.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eRecommendations\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eFor Public Health Systems\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eDevelop and implement comprehensive heat-health action plans incorporating early warning systems, public communication campaigns, vulnerable population outreach, and healthcare coordination protocols.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eStrengthen infectious disease surveillance systems to detect climate-driven changes in disease transmission patterns, incorporating climate variable monitoring and spatiotemporal modeling.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eEstablish air quality monitoring networks and warning systems, with particular attention to vulnerable populations and regions with air pollution exposure disparities.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eTrain healthcare workers to recognize and manage heat-related illness, climate-related infectious diseases, and air pollution-related exacerbations of chronic disease.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eEstablish research programs examining climate-health interactions, vulnerable population pathways, and effectiveness of adaptation interventions in diverse settings.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eFor Healthcare Systems\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003ePrepare clinical protocols for managing increased heat-related illness, particularly in occupational and outdoor worker populations.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eDevelop capacity for managing climate-sensitive infectious diseases, incorporating diagnostic, therapeutic, and prevention protocols.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eEstablish vulnerable population identification and outreach protocols to ensure high-risk individuals receive targeted preventive services.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eProvide clinician education on climate change health impacts and evidence-based preventive and therapeutic approaches.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eFor Urban Planning and Infrastructure\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003ePrioritize cooling strategies including urban green space expansion, reflective infrastructure, and building energy efficiency improvements, with particular attention to low-income neighborhoods.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eIncorporate climate change health risks into infrastructure planning, particularly for water systems, drainage, and emergency response capacity.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSupport active transportation infrastructure (pedestrian pathways, bicycle lanes) that reduces air pollution exposure while increasing physical activity.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eFor Energy and Economic Policy\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eAccelerate transition to renewable energy sources, recognizing health co-benefits alongside climate mitigation.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eImplement air quality standards that account for climate change impacts on pollutant concentrations.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSupport workers and communities affected by fossil fuel industry transitions, ensuring equitable distribution of economic costs and benefits of energy transition.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eInvest in adaptation infrastructure, particularly in low-income and vulnerable regions.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eFor International Cooperation and Equity\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eEstablish mechanisms through which high-income countries support climate adaptation efforts in vulnerable low-income regions.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSupport capacity-building for health surveillance, early warning systems, and healthcare service delivery in low-income countries.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eEnsure that climate mitigation policies account for health equity concerns and preferentially benefit vulnerable populations.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eSupport research in low-income regions examining climate-health interactions in local contexts.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eThe Z.O came up with the research topic and got all co-authors who modified the topics and started the compilation by given each authors their roles and worked in the methodology while I.M worked in the introduction to objectives, T.A work in results to temporal and geographic patterns, A. A worked on air pollution to wildfire smoke and air quality, I.O and Z.O worked on infectious disease, W. K and D.M worked on discussion and we all worked together on recommendations and recommendation.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eWant to acknowledge God almighty for life and all authors for their immense contribution to achieving this also my husband Mr. Olawale Ajibua for his support to get to this feet.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBarnett J, Adger WN. Climate change, human security and violent conflict. Political Geogr. 2007;26(6):639\u0026ndash;55.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBrunekreef B, Holgate ST. Air pollution and health. Lancet. 2002;360(9341):1233\u0026ndash;42.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eConfalonieri U, Menne B, Akhtar R, Ebi KL, Hauengue M, Kovats RS, Woodward A. Human health. 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Cities are not different from the rest of the.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"climate change, human health, heat stress, air pollution, infectious diseases, climate adaptation, health equity, public health, environmental health, vulnerable populations","lastPublishedDoi":"10.21203/rs.3.rs-8023487/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8023487/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eClimate change poses unprecedented threats to human health through multiple interconnected pathways. This literature review synthesizes current scientific evidence on three primary mechanisms linking climate change to adverse health outcomes: heat stress, air pollution, and infectious diseases. A systematic review of peer-reviewed literature published between 2000 and 2024 was conducted using PubMed, Web of Science, and Google Scholar databases. Thirty high-quality studies were identified and critically appraised using standardized quality assessment criteria. Evidence demonstrates that rising global temperatures increase heat-related morbidity and mortality, particularly among vulnerable populations. Climate-driven changes in meteorological patterns exacerbate air pollution episodes, with implications for respiratory and cardiovascular disease. Temperature and precipitation changes alter infectious disease transmission dynamics, potentially expanding geographic ranges of vector-borne and waterborne diseases. The health impacts of climate change are distributed unequally, with disproportionate effects on low-income populations, elderly individuals, and those with pre-existing conditions. Adaptation strategies including heat-health action plans, improved air quality management, and enhanced disease surveillance, combined with aggressive climate mitigation, represent essential responses to protect human health. This review underscores the urgent need for coordinated, multisectoral action to address climate-related health risks and advance health equity in a changing climate.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e","manuscriptTitle":"Climate Change and Human Health: Understanding the Risks of Heat Stress, Air Pollution, and Infectious Diseases","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-05 01:47:27","doi":"10.21203/rs.3.rs-8023487/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"c3f4b5ad-3e17-49d2-80ab-7b6142f150f7","owner":[],"postedDate":"November 5th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-12T05:40:35+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-05 01:47:27","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8023487","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8023487","identity":"rs-8023487","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}