The Changing Incidence of Malaria in Indonesia: A 9-Year Analysis of Surveillance Data

Objectives: This study aims to track the spatiotemporal incidence rate and endemicity of malaria in 34 provinces of Indonesia from 2014 to 2022 using surveillance data, commenting on trends observed and deriving implications for public health practice for combating malaria in Indonesia.Methods: This paper is a longitudinal study using routinely collected public health surveillance data. We calculated the incidence rate as both total cases and the number of cases per 1000 person-years at the provincial level. The endemicity was mapped as the annual parasite index (API) per 1000 at-risk populations. Trends in malaria incidence rate and endemicity were examined descriptively in Excel Version 16.83.Results: Nationally, malaria incidence increased by 191,503 from 2014 to 2022. The API at the national level rose by 62.63% from 0.99 cases per 1000 at-risk populations in 2014 to 1.61 in 2022. Despite the national increase, the endemicity of Sumatra Island and Kalimantan showed strong progress (API less than 1 per 1000 at-risk population). The incidence and endemicity of malaria remain high in the Eastern Islands, particularly in the provinces of Papua and West Papua. The Eastern Islands accounted for 95.73% (424,569 cases of total cases 443,530) of national cases in 2022.Conclusions: Progress has been made in province-level malaria elimination, especially outside Papua and West Papua. To prevent the persistence of endemic malaria pockets in Papua and West Papua, there is a need for greater coordination of and further dedication of financial resources toward efforts to eliminate malaria in these provinces. These efforts should be supported by an improvement in surveillance capacity, the inclusion of information on the parasite species responsible for malaria cases in routine surveillance initiatives, and the use of culturally tailored interventions to maximize health-seeking behaviors and intervention uptake.