# Co-infections of malaria and dengue in Timika, a highly endemic malaria area in Central Papua, Indonesia

## TL;DR

This study reports on malaria and dengue co-infections in Timika, Indonesia, highlighting the challenges in diagnosis and the genetic traits of the dengue virus.

## Contribution

The study provides new insights into the co-infection dynamics and genetic characteristics of DENV in a highly malaria-endemic region.

## Key findings

- Three out of 69 malaria patients were co-infected with DENV-2 and DENV-4.
- The DENV-4 strains were identified as Genotype II, closely related to strains from Makassar, Indonesia.
- Co-infections pose clinical and diagnostic challenges due to overlapping symptoms.

## Abstract

Malaria and dengue are two important infectious diseases in Indonesia, but information about their co-infections is still limited. This study aimed to describe malaria–dengue co-infections in Timika, Papua, including the clinical manifestations and genetic characteristics of the infecting dengue virus (DENV).

Sixty-nine microscopy-confirmed malaria patient samples from Timika, a malaria-highly endemic region in Central Papua province, Indonesia collected in 2022 were screened for DENV infection using qRT-PCR. Malaria speciation was performed using qRT-PCR. The whole genomes of the viruses were sequenced using MinION Oxford Nanopore Technology, and the phylogenetic analysis was inferred to determine the origin, genotype, and genetic characteristics of the viruses.

Out of 69 malaria-positive samples, three patients (4.3%) were co-infected by DENV-2 (1 patient) and DENV-4 (2 patients). The infecting parasites were P. vivax, P. falciparum, and P. malariae as determined using qRT-PCR. The whole genomes of the infecting DENV-4 were successfully sequenced and phylogenetic analysis revealed the genotype of the virus as Genotype II, which were closely related to DENV strains from Makassar city in South Sulawesi province, Indonesia.

This study demonstrates the occurrence of malaria and dengue co-infections in Timika, Central Papua, Indonesia, with a prevalence of 4.3%. The co-infection poses a unique clinical and diagnostics challenges due to overlapping symptoms and potential complications. This finding highlights the diagnostic difficulties, clinical presentations, and future possibilities for such cases. The genomic data of DENV obtained from these cases provide new information about virus circulation in Indonesia and support the importance of combining clinical and molecular approaches for surveillance.