Environmental health factors and dengue risk mapping using spatial-AHP: A case study in Nakhon Nayok Province,...

Dengue fever is a rapidly spreading mosquito-borne disease, particularly in tropical countries like Thailand, However, limited research has examined the role of household-level environmental health factors in dengue transmission, especially through spatial multi-criteria decision analysis. This study aimed to apply the Analytic Hierarchy Process (AHP) within a Geographic Information System (GIS) environment to assess dengue risk areas based on environmental health factors in Nakhon Nayok Province, Thailand. A literature review was conducted to identify key environmental health risk factors, which informed questionnaire development and guided field data collection. These included presence of plastic or natural containers, lack of door/window screens, drainage systems, private trash bins, waste burning, agricultural and forested areas, small household size, and housing type. AHP was used to assign relative weights to environmental health factors and spatial units (districts) criteria. The weighted criteria were incorporated into spatial analysis to generate a dengue risk map, which classified areas into five risk levels. The most influential environmental health risk factors were inadequate drainage, absence of door/window screens, and poor waste management practices. High-risk zones were concentrated in Mueang Nakhon Nayok and parts of Pak Phli District, whereas Ban Na and Ongkharak Districts were predominantly low risk. The integration of AHP and GIS in this study demonstrates a conceptual framework for identifying localized dengue risk zones under data-limited conditions. The resulting risk map functions as an illustrative decision-support layer for preliminary prioritization, rather than a predictive epidemiological model.