Twenty-two years of dengue outbreaks in Bangladesh: epidemiology, clinical spectrum, serotypes, and future disease risks

Abstract

Dengue is the most rapidly spreading mosquito-borne disease and has become a major public health threat, particularly for tropical and subtropical countries including Bangladesh. This comprehensive review aims to summarize the overall scenario of dengue, including disease burden, clinical spectrum, seroprevalence, circulating serotypes/genotypes, and spatial distribution since the first recorded outbreak in Bangladesh. Since the first recorded outbreak in 2000, dengue epidemiology has shown the typical epidemic pattern with more frequent and bigger outbreaks and gradual geographic expansion to non-endemic regions in Bangladesh. For instance, highly confined Rohingya refugee camps that provide shelters to nearly 1.2 million forcibly displaced vulnerable Myanmar nationals in Cox's Bazar district confronted a massive outbreak in 2022. Recent major outbreaks are found to be associated with the emergence of serotype DENV-3, which was undetected for a long time. Consequently, changes in serotypes might be attributed to increased severity in clinical manifestation in recent years. The existing weak surveillance and risk management systems are inadequate to deal with impending dengue risks. The healthcare system, particularly at the district level, is not prepared to manage impending large-scale dengue outbreaks in Bangladesh. Our findings would contribute to the development of strategies for dengue control and management in Bangladesh as well as other similar settings elsewhere in the world.

Fig. 1

Systematic search for journal articles describing dengue in Bangladesh

Fig. 2

Seasonality of dengue outbreaks in Bangladesh between 2010 and 2021. Publicly available data were obtained from the Directorate general of health services, Bangladesh

Fig. 3

Maps showing the districtwise spatial distribution of dengue reported cases in 2019 (A), 2021 (B) & 2022 (C) outbreaks in Bangladesh excluding cases from historical outbreak epicenter Dhaka city and emerging epicenter Rohingya Refugee camps. Publicly available data were obtained from the Directorate general of health services, Bangladesh

Fig. 4

Map of Bangladesh showing dengue reported cases without travel history away from epicenter Dhaka in the 2019 outbreak along with species distribution of Ae. aegypti and Ae. Albopictus. Secondary data for dengue cases [10] and mosquitos were retrieved from the previous studies [11], respectively