Socio-demographic characteristics and parasite density patterns of Plasmodium knowlesi Malaria in Aceh, Indonesia: insights from hospital-based data.

introductionPlasmodium knowlesi has emerged as an important zoonotic malaria in Southeast Asia. While most cases are reported from Malaysia, increasing reports from Indonesia, including Aceh Province, highlight the need for local epidemiological data.

methodsA retrospective, hospital-based study was conducted using secondary data from a hospital in Aceh Besar, Indonesia. Medical records of all patients confirmed positive P. knowlesi infection by microscopy and polymerase chain reaction (PCR) between January 2023 and April 2024 were reviewed. Data on socio-demographic variables, clinical presentation, treatment, outcomes, and parasite density were extracted and analysed.

resultsA total of 40 confirmed P. knowlesi malaria patients' data were analysed. The median age was 31 years (IQR: 25-43). Farmers and plantation workers represented the largest occupational group (67.5%), followed by orangutan (great ape) caretakers (10%). All patients presented with fever and headache and were treated with dihydroartemisinin-piperaquine and primaquine, with complete recovery. Most cases occurred between April and July 2023. Parasite density analysis was performed on 35 patients with completed data, which was classified as high in 42.9%, moderate in 45.7%, and low in 11.4% of patients. Median hospital stay was three days, with longer stays observed among patients with lower parasite density.

conclusionsThis study demonstrates that P. knowlesi malaria predominantly affects adult males engaged in forest-related occupations in Aceh Province, Indonesia. Therefore, continue surveillance of infection and context-specific, targeted interventions among high-risk occupational groups are needed to prevent and control zoonotic malaria in Indonesia.