Environmental health factors influencing dengue: a systematic review with thematic categorization

Environmental conditions significantly influence dengue fever transmission by affecting Aedes mosquito breeding. This systematic review aimed to identify and synthesize environmental health factors associated with dengue risk. A comprehensive search across multiple databases yielded 64 studies conducted in urban, peri-urban, and rural settings. Data were extracted and categorized thematically, and risk of bias was assessed using the JBI Checklists, Newcastle-Ottawa Scale, and ROBINS-I tool, depending on study design. Eight key environmental health factors were identified: water storage practices, solid waste disposal, housing characteristics, drainage and standing water, vegetation and shaded areas, urbanization and population density, climate and seasonal variation, and water supply reliability. Improper water storage and unmanaged waste were consistently linked to higher mosquito entomological indices. Poor housing conditions and densely populated urban areas also correlated with increased dengue risk. Seasonal rainfall and unreliable water infrastructure intensified vulnerability, particularly in resource-limited contexts. Findings emphasize that environmental health conditions are central to dengue prevention. Effective control requires multi-sectoral strategies that integrate infrastructure upgrades, environmental management, and behavioural change. Future research should prioritize evaluating environmental interventions and developing predictive models incorporating climate, infrastructure, and human behaviour to guide public health responses.