# Spatial Risk Factors of Vector-Borne Diseases in Pacific Island Countries and Territories: A Scoping Review

## TL;DR

This study reviews how environmental, demographic, and socio-economic factors influence vector-borne diseases in Pacific Island countries, highlighting the need for spatially targeted control strategies.

## Contribution

The study provides a comprehensive synthesis of spatial risk factors for vector-borne diseases in a geographically dispersed and climate-sensitive region.

## Key findings

- Environmental factors like temperature and precipitation are consistently linked to vector-borne diseases in Pacific Island Countries and Territories.
- Spatial socioeconomic factors such as low income and limited education are positively correlated with disease burden, especially for lymphatic filariasis and dengue.
- Infrastructure, healthcare access, and intra-island mobility remain underexplored areas in the literature.

## Abstract

This scoping review aimed to identify and synthesise spatially relevant environmental, demographic, and socio-economic factors associated with vector-borne diseases (VBDs) in Pacific Island Countries and Territories (PICTs), a region particularly vulnerable due to its ecological and climate diversity. A systematic search of PubMed, Scopus, and Web of Science was conducted in March 2025 with no time restrictions, yielding 3008 records. After applying the inclusion criteria, 21 studies were selected for analysis. Environmental factors such as temperature, precipitation, and land cover were consistently associated with increased burden of malaria, dengue, and lymphatic filariasis, while associations with elevation and flooding were mixed or inconclusive. Demographic factors, including population density and household composition, were found to be associated with disease occurrence, although the direction and the strength of these associations varied. Three studies reported a negative association between population density and disease outcomes, including lymphatic filariasis in American Samoa and dengue in New Caledonia. Spatial socioeconomic factors such as low income, unemployment, and limited education were positively correlated with disease burden, particularly lymphatic filariasis and dengue. These findings underscore the importance of spatial determinants in shaping VBD transmission across PICTs and highlight the utility of spatial risk mapping to inform geographically targeted vector control strategies. Notably, infrastructure, health care access, and intra-island mobility remain underexplored in the literature, representing critical gaps for future research. Strengthening surveillance through spatially informed public health planning is essential to mitigate disease burden in this climate-sensitive and geographically dispersed region.