Epidemiological Distribution of Dengue Cases and Risk Mapping for Aedes Mosquito Including Preventive Practices Based on Integrated Vector Management Strategies in Dhaka City

Abstract

Background: Dengue fever, transmitted mainly by Aedes aegypti and Aedes albopictus, remains a persistent public health concern in Bangladesh, particularly in Dhaka City, where high population density, unplanned urbanization, and poor waste management facilitate mosquito breeding.

Objective: This study aims to find out the epidemiological distribution of dengue cases, identify temporal trends, and evaluate vector dominance and demographic vulnerabilities to guide integrated vector management strategies in Dhaka city.

Methods: A descriptive cross-sectional analysis was conducted using secondary data extracted from the daily dengue press releases of the Directorate General of Health Services (DGHS), Bangladesh, covering the period from 20 March to 2 May 2024. Additional information was obtained from the National Malaria Elimination and Aedes-transmitted Diseases Control Program (CDC, DGHS). Statistical and spatial analyses were performed to examine trends in cases and mortality, as well as the age and gender distribution of patients and the composition of vector species.

Results: A total of 646 confirmed dengue cases and 7 deaths were recorded in Dhaka City during the study period, corresponding to a case fatality ratio (CFR) of 1.08%. Daily admissions increased steadily from late March, peaking on April 21 (37 cases), followed by a gradual decline in early May. Young adults aged 15–29 years were most affected (36.5%), followed by those aged 30–44 years (25.2%). Children under 15 years accounted for 16.8%, while 10.9% were aged 45–59 years, and 4.7% were 60 years or older. Males comprised 64.9% of total cases, indicating higher occupational and outdoor exposure. Spatial mapping identified high-risk clusters in DNCC wards 1–10 and DSCC wards 23–36, particularly near construction sites, drains, and areas with poor waste disposal. Aedes aegypti remained the dominant species (96–100%), while Aedes albopictus accounted for 0–3.98%.

Conclusion: The findings confirm Aedes aegypti as the principal dengue vector and mid-April as the critical pre-monsoon transmission peak. Strengthening early vector surveillance, enforcing waste management, and promoting community participation in Integrated Vector Management (IVM) are vital for sustainable dengue control in Dhaka City.