# A study protocol for a baseline community-based cross-sectional study to investigate malaria and dengue transmission dynamics in a development area of new capital city, Indonesia

## TL;DR

This study will investigate malaria and dengue transmission in Indonesia's new capital city by analyzing blood samples and environmental data to identify infection hotspots.

## Contribution

The study introduces serological surveillance in a development area to assess historical exposure to malaria and dengue, integrating geospatial data for risk mapping.

## Key findings

- Blood samples from 2,000 participants will reveal seroprevalence of malaria and dengue.
- Geospatial analysis will identify high-risk areas for disease transmission.
- Findings will inform health planning for Indonesia's new capital region.

## Abstract

The relocation of Indonesia's capital to Ibu Kota Nusantara (IKN) in East Kalimantan, a malaria and dengue hotspot, presents new risks of infectious disease transmission due to land-use changes and population movements. Current knowledge on the impact of these changes on vector-borne diseases, especially
Plasmodium knowlesi malaria and other arboviruses, is limited. Serological surveillance offers a robust method for assessing population exposure.

A community-based cross-sectional study will be conducted in IKN and its surrounding area, in East Kalimantan. Approximately 2,000 individuals aged >1 year will be enrolled. Finger-prick blood samples will be collected for serological analysis (multiplex bead-based assays for malaria species, and dengue virus serotypes) and malaria RDTs. Demographic, clinical, environmental, and geolocation data will also be collected. Statistical and geostatistical models will be used to assess seroprevalence, spatial patterns, and risk factors of exposure to malaria and dengue.

Our study aims to understand the historical transmission risk of malaria and dengue among communities living in and around the new capital city. We will recruit around 2,000 people, aged ≥1 year old from randomly selected households in a development area of new capital city, Indonesia.

From each consenting participant, we will take a finger-prick blood sample. This sample will be used for two purposes: first, a malaria diagnostic test (RDT), so we can refer to anyone who is ill for immediate treatment. Second, we will use laboratory tests to look for antibodies in the blood. Antibodies are a sign that a person’s immune system has been exposed to infections (or vaccinations) in the past. In our study, we aim to estimate the proportion of the population who have been exposed to malaria or dengue infections in the past, even if they never felt ill.

By integrating health data with satellite-derived environmental data, we will identify hotspots where the risk of infection is highest and understand the factors that drive disease transmission. This information will be important evidence for the Indonesian Ministry of Health in planning effective disease control programmes and protecting the health of people living in these areas.