Bold claim: climate change is quietly fueling a global health crisis that could become a creeping catastrophe if ignored. That is the central warning from a major international study led by The Global Health Network at Oxford’s Nuffield Department of Medicine, and commissioned by Wellcome. The findings, published in Nature Scientific Reports, draw on insights from 3,752 health professionals and researchers across 151 countries, with nearly 87% of participants from low- and middle-income nations. The research concludes that climate change, poverty, and antimicrobial resistance are converging to worsen health outcomes in a way that may not trigger a dramatic new outbreak, but will steadily erode health and resilience over time.
Across Africa, Asia, and Latin America, experts identify vector-borne diseases—especially malaria and dengue—as the fastest-growing threats, followed by tuberculosis and HIV/AIDS. The study attributes three primary drivers of this escalation:
- Climate change, including higher temperatures and altered rainfall patterns, which expand the habitats of vectors like mosquitoes, create more breeding sites, and boost human movement and displacement.
- Socioeconomic inequality, shaping living conditions and access to essential healthcare.
- Antimicrobial resistance, undermining the effectiveness of treatments for numerous infections worldwide.
Professor Trudie Lang, director of The Global Health Network and senior author, emphasizes that the study provides unprecedented, globally representative evidence from communities experiencing these climate-related threats now, especially in the Global South where disease burdens are highest. She notes that under-representation and limited collective voice from these regions have historically masked such realities, but the data reflect lived experiences and diverse perspectives. The takeaway is sobering: the next major health emergency may come not from a sudden new pathogen but from the slow, persistent deterioration of familiar diseases that claim lives daily.
Environmental conditions driven by rising temperatures, floods, and droughts create ideal environments for mosquitoes, ticks, and harmful bacteria. Extreme weather further strains fragile health systems, reducing capacity to prevent, detect, and treat infections.
The researchers argue that this risk will manifest as a slow-moving humanitarian disaster—endemic diseases migrating into new geographies, disrupting health services and weakening economies. Addressing the intertwined drivers of disease is portrayed as essential for strengthening preparedness against both current and future health threats. The study calls for sustained investment in diagnostics, surveillance, and equitable research partnerships that empower local leadership and build durable research capacity.
Dr. Aliya Naheed, Country Director of NIHR GHR Centre for NCDs and Environmental Change in Bangladesh, highlights the stark disparities in health priorities between LMICs and high-income countries. She underscores the need for equitable global investment to prevent and control common infectious diseases in LMICs, recognizing climate change as a key factor shaping future health emergencies.
The Wellcome commission project aligns with an expanding focus on environmental medicine, which increasingly considers how soil, water, and air pollutants intersect with climate change to affect health. Josie Golding, Wellcome’s Head of Epidemics and Epidemiology, reinforces that urgent climate action paired with investment in innovative technologies and approaches is necessary to curb the spread of diseases like malaria, dengue, and chikungunya. Without coordinated action on both climate policy and health innovation, health inequities will likely widen, and vulnerable populations will bear the brunt.
Source: University of Oxford
03.12.2025
