Overlapping Environmental Shocks and Arboviral Risk: Earthquakes as an Underrecognized Catalyst

The epidemiology of dengue and other arboviral diseases is increasingly shaped by the convergence of viral, environmental, and societal drivers operating across multiple spatial and temporal scales. Climate change, rapid urbanisation, biodiversity loss, and intensified human mobility collectively contribute to the expansion and re-emergence of arboviruses, particularly in regions characterised by structural fragility and limited public health capacity. In this context, Nakhaie et al. provide a timely and comprehensive synthesis of the viral, environmental, and human factors driving arboviral expansion, offering a robust multidimensional framework for understanding current and future epidemiological trends [1]. Building on this framework, increasing attention should be directed towards how acute disruptive events interact with chronic environmental and infrastructural stressors to amplify arboviral transmission risk. In many endemic and climate-vulnerable regions, arboviral transmission no longer results from isolated drivers, but rather from the convergence of long-term pressures (such as climate change, fragile infrastructure, and constrained health systems) and sudden shocks that reshape vector ecology, population exposure, and disease surveillance capacity. Natural disasters exemplify this convergence. While floods and cyclones are frequently discussed in relation to vector-borne diseases, earthquakes remain relatively underexplored in the arboviral literature, despite their distinctive capacity to simultaneously disrupt water and sanitation systems, housing stability, population distribution, and healthcare delivery [2]. These features make seismic events particularly effective catalysts for arboviral amplification. Available evidence indicates that earthquakes create ecological and socio-environmental conditions highly conducive to the proliferation of Aedes mosquitoes and the transmission of dengue, chikungunya, Zika, and yellow fever viruses [2, 5]. Damage to water distribution and wastewater infrastructure frequently forces affected populations to rely on open water storage containers, while debris accumulation, land deformation, and impaired drainage generate widespread stagnant water pools that serve as ideal mosquito breeding sites [2, 8]. Concurrently, housing destruction and displacement into temporary shelters substantially increase human–vector contact, particularly in endemic settings [6]. Healthcare systems, often already strained, are overwhelmed by trauma care needs, resulting in the interruption of routine vector surveillance, control programs, and diagnostic capacity [8]. These earthquake-related mechanisms rarely operate in isolation. When seismic events occur in regions already affected by climate change, rising temperatures and altered precipitation patterns further accelerate mosquito life cycles, enhance vector competence, and shorten the extrinsic incubation period of arboviruses, intensifying transmission dynamics [2, 5]. The interaction between seismic disruption and climate-driven ecological change therefore creates a high-risk environment for arboviral amplification, as summarised in Table 1. Historical precedents support this association. Following the 2005 Kashmir earthquake, increases in vector-borne diseases were attributed to ecological disruption and compromised health services [2]. After the 2010 Haiti earthquake, alongside the well-documented cholera epidemic, dengue transmission intensified in overcrowded settings with deteriorating sanitation [7]. Similarly, post-earthquake assessments following the 2015 Nepal earthquake highlighted conditions conducive to increased vector-borne disease transmission [6]. Collectively, these experiences indicate that arboviral outbreaks represent a predictable secondary public health crisis following major seismic events. The recent 7.7-magnitude earthquake in central Myanmar in March 2025 illustrates the contemporary relevance of this issue. According to the World Health Organization, the event caused extensive casualties and overwhelmed a healthcare system already weakened by prolonged political instability and humanitarian crises [3]. In this context, routine disease surveillance and vector control activities have been severely disrupted, while population displacement, fragile living conditions, and limited access to healthcare further heighten the risk of infectious disease emergence, as observed in other displacement-driven crises in Southeast Asia [4, 9, 10]. Post-earthquake conditions—including stagnant water accumulation, overcrowded shelters, and reduced diagnostic capacity—may therefore facilitate undetected arboviral amplification. Addressing arboviral risk in post-earthquake settings requires a proactive, multisectoral approach that complements immediate humanitarian response. Early entomological surveillance, geospatial identification of breeding sites, and targeted vector control interventions should be integrated into disaster response frameworks, alongside efforts to maintain essential healthcare services and disease surveillance [8]. In conclusion, the framework proposed by Nakhaie et al. provides a strong foundation for understanding arboviral expansion. We argue that earthquakes should be explicitly recognized within this framework, not as isolated hazards, but as catalytic events that amplify pre-existing environmental and infrastructural vulnerabilities. Integrating arbovirus surveillance and control into earthquake preparedness and response plans, particularly in dengue-endemic and climate-sensitive regions, will be essential to reducing the long-term infectious disease burden following seismic disasters. Giancarlo Ceccarelli: conceptualisation, investigation, writing – original draft, writing – review and editing. Francesco Branda: investigation, writing – original draft, writing – review and editing. Marta Giovanetti: investigation, writing – original draft, writing – review and editing. Fabio Scarpa: investigation, writing – original draft, writing – review and editing. Gabriella d’Ettorre: investigation, writing – original draft, writing – review and editing. Massimo Ciccozzi: supervision, validation, writing – original draft, writing – review and editing. The authors declare no conflicts of interest. The authors have nothing to report.