Background and objectives: Dengue virus (DENV) and chikungunya virus (CHIKV) are important Aedes-borne arboviruses that frequently co-circulate in tropical regions, posing diagnostic and public health challenges because of their overlapping clinical features. This study investigated the prevalence and distribution pattern of dengue, chikungunya, and their co-infection among clinically suspected arboviral febrile cases attending a tertiary care hospital in Dhaka city, Bangladesh.

Materials and methods: Patients with acute fever attending both the in and out-patient departments of a tertiary care hospital in Dhaka city between July and September 2025were included in the study. Serum samples were tested for DENV (dengue virus), CHIKV (chikungunya virus) and ZIKV (zika virus) by real time multiplex RT-PCR. Demographic data of patients were collected from the hospital register.

Results: A total of 970 acute febrile cases were included in the study. CHIKV was detected in 557 (57.4%), DENV in 71 (7.3%), and DEN–CHIK co-infection in 15 (1.5%) patients, while 327 (33.7%) patients tested negative. CHIK infection predominated during July and August, whereas DEN infection increased significantly in September. Co-infection was uncommon but peaked in August. Male patients had significantly higher rates of CHIK infection and co-infection than females, while no significant age-related differences were observed.

Conclusions: The low co-infection rate of DENV and CHIKV in our study is comparable to reports from other endemic countries, suggesting limited temporal overlap of DENV and CHIKV transmission despite their co-circulation. These findings highlight the value of integrated arboviral surveillance for accurate diagnosis, timely outbreak detection, and effective public health interventions in Bangladesh.

July 2026; Vol. 20(2):005. DOI: https://doi.org/10.55010/imcjms.20.014

*Correspondence: Prof. Md. Shariful Alam Jilani, Department of Microbiology, Ibrahim Medical College. Email: jilanimsa@gmail.com

© 2026 The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License(CC BY 4.0)