Humanity’s pressure on the natural environment not only leads to an ecological crisis but also poses a serious threat to public health. Greenhouse gas emissions, deforestation, intensive agricultural production, and changes in land use are rapidly disrupting the ecological balances that have long protected human health. According to the IPCC’s latest assessments, if current policies continue, global temperatures are expected to rise by at least 2°C, and by 2.9°C in some scenarios. This warming has particularly critical consequences for public health.
Rising temperatures and changing precipitation patterns are fundamentally transforming the habitats of arthropod vectors. Many vector species, particularly mosquitoes and ticks, are spreading into regions that were previously unsuitable for these organisms. It is suggested that malaria cases are increasing in mountainous areas where temperatures remain below the threshold for transmission; conversely, transmission rates may decrease in regions where the average temperature exceeds 25°C. Similarly, the encroachment of species such as Aedes aegypti and Aedes albopictus into cooler climates is paving the way for the emergence of tropical diseases like dengue fever, chikungunya, and the Zika virus in new geographic areas. Rising temperatures also affect the rate of pathogen development within the vector, a factor that can increase its transmission potential.
Zoonotic Diseases and Pathogen Transmission
Approximately 62 percent of new infectious diseases are of zoonotic origin, and the vast majority of these are linked to wild animal reservoirs. Deforestation and changes in land use are forcing wild species into increasingly close contact with humans; this process elevates the risk of pathogen transmission. Ebola, the Nipah virus, and SARS-related coronaviruses are among the concrete examples of this mechanism. Intensive animal husbandry also increases this risk: Animals kept at high densities in confined spaces provide a favorable environment for viral adaptation and amplification. Influenza viruses are of particular concern due to genetic reassortment processes in pigs.
Antimicrobial Resistance: A Growing Threat Linked to Climate Change
Antimicrobial resistance is a public health problem that is directly intertwined with the climate crisis and is becoming increasingly severe. Rising environmental temperatures facilitate horizontal gene transfer among bacteria and accelerate the spread of resistance mechanisms. Extreme weather events, such as floods and hurricanes, damage health infrastructure and increase antibiotic use, thereby promoting the selection of resistant strains. In particular, crowded environments with inadequate sanitation—such as refugee camps and displaced communities—can become hotspots for the rapid spread of multidrug-resistant pathogens.
All these developments are bringing the need for biocidal products and the importance of research in this field back into focus. The effectiveness and sustainability of vector control strategies must be reevaluated in light of changing geographic distribution patterns. Furthermore, the environmental dispersion of disinfectants and antimicrobial compounds must be carefully monitored for its contribution to the development of resistance.
In conclusion, the relationships between the climate crisis, infectious diseases, and antimicrobial resistance are complex and multifaceted. A better understanding of these connections should be a key priority for both national health policies and research agendas in the field of biocides.
Note: This article was prepared by Dr. Didem Yüzügüllü based on data from the review article titled “Insights into the ecological and climate crisis: Emerging infections threatening human health,” published by Segala et al. in the journal *Acta Tropica* in 2025.