Mapping of regional vulnerability to determine malaria using physical, climate, and socio-demographic variables in Purworejo Regency, Central Java

Abstract

Malaria is a mosquito-borne disease caused by the existence of the <i>Plasmodium</i> parasite in female <i>Anopheles</i> mosquitoes. Tropical countries, such as Indonesia, provide a suitable place for these mosquitos to live and breed quite easily. Despite having an overall low case incidence, some regions in Java still have it worse than others. Purworejo Regency holds the highest place in this regard, with an Annual Parasite Incidence (API) value of 1.96 for every 1,000 population. This research aims to utilize physical, climate, and socio-demographic variables as a parameter for malaria incidence in Purworejo Regency, as well as to map the vulnerability of the said area towards malaria. Physical variables included vegetation density, landuse and landcover, elevation, and soil texture, while climate variables included rainfall and humidity. Settlement density was used as a socio-demographic variable in the emergence of malaria. Each of these variables weights was then calculated with Analytical Hierarchy Process (AHP) based on their ranks, resulting in elevation being the most prominent variable. The overlay was used to combine all the variables as well as to calculate the total score for existing polygons to decide their classification. The generated map from this particular scenario showed that Menoreh Mountains in the northern region and settlements close to dense vegetation in the southern region of Purworejo Regency were vulnerable to malaria. Moderately vulnerable class dominated 55.23% of Purworejo Regency, followed by 35.41% of the vulnerable class, and lastly 9.36% of the non-vulnerable class. Malaria cases from Purworejo Public Health Center year 2007-2011 were used as a comparison. Not all incidents that happened on-field fit perfectly within the generated map. As such, further research involving other variables and the latest malaria case as a comparison are needed.