Choudhury, M.-U.-I., C. E. Haque, A. Nishat, and S. Byrne. 2021. Social learning for building community resilience to cyclones: role of indigenous and local knowledge, power, and institutions in coastal Bangladesh. Ecology and Society 26(1):5. https://doi.org/10.5751/ES-12107-260105

Dengue virus (DENV) activity has been reported in Dhaka, Bangladesh since the early 1960s with the greatest burden of dengue fever and dengue hemorrhagic fever cases observed in 2000. Since this time, the intensity of dengue activity has varied from year to year, and its determining factors remained relatively unknown. In light of such gaps in knowledge, the main objectives of this study were to determine the magnitude of seroprevalence and seroconversion among the surveyed population, and establish the individual/household level risk factors for the presence of DENV antibodies among all age groups of target populations in the city of Dhaka. Considering the lack of fine scale investigations on the factors driving dengue activity in Bangladesh, a prospective cohort study involving serological surveys was undertaken with participant interviews and blood donation across the city of Dhaka in 2012. Study participants were recruited from 12 of 90 wards and blood samples were collected during both the pre-monsoon (n = 1125) and post-monsoon (n = 600) seasons of 2012. The findings revealed that the seroprevalence in all pre-monsoon samples was 80.0% (900/1125) while the seropositivity in the pre-monsoon samples that had paired post-monsoon samples was 83.3% (503/600). Of the 97 paired samples that were negative at the pre-monsoon time point, 56 were positive at the post-monsoon time point. This resulted in a seroprevalence of 93.2% (559/600) among individuals tested during the post-monsoon period. Seroprevalence trended higher with age with children exhibiting a lower seropositivity as compared to adults. Results from this study also indicated that DENV strains were the only flaviviruses circulating in Dhaka in 2012. A multivariate analysis revealed that age, possession of indoor potted plants, and types of mosquito control measures were significant factors associated with DENV seroprevalence; while attendance in public/mass gatherings, and use of mosquito control measures were significantly associated with DENV seroconversion after adjusting for all other variables. Our study suggests that there is a high level of endemic dengue virus circulation in the city of Dhaka which has resulted in significant DENV seroprevalence among its residents. Seropositivity increased with age, however, a substantial proportion of children are at risk for DENV infections. Our serological analysis also documents considerable DENV seroconversion among study participants which indicates that a large proportion of the population in the city of Dhaka were newly exposed to DENV during the study period (pre-and post-monsoon 2012). High levels of seroconversion suggest that there was an intense circulation of DENV in 2012 and this may have resulted in a significant risk for viral associated illness. Findings of our study further indicated that home-based interventions, such as removing indoor potted plants and increased bed net use, in addition to vector control measures in public parks, would reduce exposure to DENV and further decrease risk of viral associated disease. Similar to many other tropical regions of the world, dengue is a major public health problem in Bangladesh where Aedes aegypti mosquitoes are the main vector. Through this serological survey, we present data on the magnitude (measured in proportions) of seroprevalence and seroconversion within 12 selected wards in the city of Dhaka, Bangladesh. In 2012 the observed dengue seroprevalence was 93% among individuals tested during post-monsoon with a seroconversion rate between pre- and post-monsoon periods of 57.7%. This finding suggests that dengue virus (DENV) circulated in the city during the observation period. Past exposure to dengue virus was highly associated with age, possession of indoor potted plants, types of mosquito control measures used, and human movement and attendance in mass gatherings, while the extent of dengue seroprevalence were not associated with the socioeconomic status of the study participants. Our findings suggest that household utilities and water management or storage practices and recognition and elimination of mosquito development sites and participation in mass gatherings are important factors that affect exposure to dengue. Intervention strategies should therefore target these factors for effective prevention and control of dengue infection.

Dengue viruses are responsible for over 100 million infections a year worldwide and are a public health concern in Bangladesh. Although risk of transmission is high, data on vector population characteristics are scanty in Bangladesh; therefore, a comprehensive prediction of the patterns of local virus transmission is not possible. Recognizing these gaps, multi-year entomological surveys were carried out in Dhaka, where the disease is most frequently reported. The specific objectives of the present study are threefold: i) to determine the risk factors for the presence of Aedes mosquitoes; ii) to identify the types of most productive and key containers; and iii) to estimate the effects of climatic factors on Aedes abundance in the city of Dhaka, Bangladesh. Entomological surveys were conducted in 12 out of 90 wards in Dhaka. These wards were selected using a probability proportional sampling procedure during the monsoon seasons in 2011, 2012 and 2013 and in the dry season in 2012. All containers inside and around sampled households were inspected for mosquito larvae and pupae, and containers were classified according to their relative size, use pattern, and materials of construction. During the study period (2011–2013), 12,680 larvae and pupae were collected. About 82% of the identified immature mosquitoes were Aedes aegypti, while the remainder were Ae. albopictus and other mosquito species. The largest number of immature mosquitoes was collected from tires and refrigerator trays during 2011 and 2012 monsoon seasons. Conversely, plastic drums were the most productive during the 2012 dry and 2013 monsoon season. Vehicle parts and discarded construction materials were the most efficient producers of Aedes mosquitoes in all surveys. The presence of Aedes mosquitoes was significantly (p < 0.05) higher in low socio-economic zones of Dhaka. Container location, presence of vegetation, and availability of shade for containers were also significantly associated with finding immature Aedes mosquitoes, based on multivariable analysis after confounder adjustment. Rainfall, temperature, and relative humidity also significantly affected the mean abundance of mosquitoes. Proper use, disposal, and recycling of the containers that effectively produce large numbers of Aedes vector mosquitoes may decrease the risk of arboviral transmission.

Purpose: Despite Bangladesh's great strides in formulating disaster management policies following the principles of good governance, the degree to which these policies have successfully been implemented at the local level remains largely unknown. The objectives of this study were two-fold: (1) to examine the roles and effectiveness of local-level governance and disaster management institutions, and (2) to identify barriers to the implementation of national policies and Disaster-Risk-Reduction (DRR) guidelines at the local community level.Design/methodology/approach: Between January 2014 and June 2015 we carried out an empirical investigation in two coastal communities in Bangladesh. We employed a qualitative research and Case Study approach, using techniques from the Participatory Rural Appraisal toolbox to collect data from local community members as well as government and NGO officials.Findings: Our study revealed that interactive disaster governance, decentralization of disaster management, and compliance by local-level institutions with good governance principles and national policy guidelines can be extremely effective in reducing disaster-loss and damages. According to coastal community members, the local governments have generally failed to uphold good governance principles, and triangulated data confirm that the region at large suffers from rampant corruption, political favoritism, lack of transparency and accountability and minimal inclusion of local inhabitants in decision-making – all of which have severely impeded the successful implementation of national disaster-management policies.Research limitations/implications: While considerable research on good governance has been pursued, our understanding of good disaster governance and their criteria is still poor. In addition, although numerous national disaster management policy and good governance initiatives have been taken in Bangladesh, like many other developing countries, the nature and extent of their local level implementation are not well known. This study contributes to these research gaps, with identification of further research agenda in these areas.Practical implications: The study focuses on good disaster governance and management issues and practices, their strengths and limitations in the context of cyclone and storm surges along coastal Bangladesh. It offers specific good disaster governance criteria for improving multi-level successful implementation. The paper deals with International Sendai Framework that called for enhancement of local level community resilience to disasters. Thus, it contributes to numerous policy and practice areas relating to good disaster governance.Social implications: Good disaster governance would benefit not only from future disaster losses but also from improved prevention and mitigation of natural hazards impact, benefiting society at large. Improvement in knowledge and practice in disaster-risk-reduction through good governance and effective management would ensure local community development and human wellbeing at the national level.Originality/value: The failure of local-level government institutions to effectively implement national disaster management and resilience-building policies is largely attributable to a lack of financial and human resources, rampant corruption, a lack of accountability and transparency and the exclusion of local inhabitants from decision-making processes. Our study identified the specific manifestations of these failures in coastal communities in Bangladesh. These results underscore the vital need to address the wide gap between national DRR goals and the on-the-ground realities of policy implementation to successfully enhance the country's resilience to climate change-induced disasters.