Prevalence of COVID-19 in Bangladesh, April to October 2020-a cross-sectional study.

Objective: The aim of this study was to estimate the proportion of symptomatic and asymptomatic laboratory-confirmed coronavirus disease 2019 (COVID-19) cases among the population of Bangladesh. Methods: A cross-sectional survey was conducted in Dhaka City and other districts of Bangladesh between April 18 and October 12, 2020. A total of 32 districts outside Dhaka were randomly selected, and one village and one mahalla was selected from each district; 25 mahallas were selected from Dhaka City. From each village or mahalla, 120 households were enrolled through systematic random sampling. Results: A total of 44 865 individuals were interviewed from 10 907 households. The majority (70%, n = 31 488) of the individuals were <40 years of age. Almost half of the individuals (49%, n = 21 888) reported more than four members in their household. It was estimated that 12.6% (n = 160) of the households had one or more severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals, among whom 0.9% (n = 404) of individuals had at least one COVID-19-like symptom, at the national level. The prevalence of COVID-19 in the general population was 6.4%. Among the SARS-CoV-2-positive individuals, 87% were asymptomatic. Conclusions: The substantial high number of asymptomatic cases all over Bangladesh suggests that community-level containment and mitigation measures are required to combat COVID-19. Future studies to understand the transmission capability could help to define mitigation and control measures.

A Controlled Trial to Reduce the Risk of Human Nipah Virus Exposure in Bangladesh.

Human Nipah virus (NiV) infection, often fatal in Bangladesh, is primarily transmitted by drinking raw date palm sap contaminated by Pteropus bats. We assessed the impact of a behavior change communication intervention on reducing consumption of potentially NiV-contaminated raw sap. During the 2012-2014 sap harvesting seasons, we implemented interventions in two areas and compared results with a control area. In one area, we disseminated a "do not drink raw sap" message and, in the other area, encouraged only drinking sap if it had been protected from bat contamination by a barrier ("only safe sap"). Post-intervention, 40% more respondents in both intervention areas reported knowing about a disease contracted through raw sap consumption compared with control. Reported raw sap consumption decreased in all areas. The reductions in the intervention areas were not significantly greater compared to the control. Respondents directly exposed to the "only safe sap" message were more likely to report consuming raw sap from a protected source than those with no exposure (25 vs. 15%, OR 2.0, 95% CI 1.5-2.6, P < 0.001). While the intervention increased knowledge in both intervention areas, the "only safe sap" intervention reduced exposure to potentially NiV-contaminated sap and should be considered for future dissemination.

Respiratory Viruses Associated Hospitalization among Children Aged <5 Years in Bangladesh: 2010-2014.

BACKGROUND: We combined hospital-based surveillance and health utilization survey data to estimate the incidence of respiratory viral infections associated hospitalization among children aged < 5 years in Bangladesh. METHODS: Surveillance physicians collected respiratory specimens from children aged <5 years hospitalized with respiratory illness and residing in the primary hospital catchment areas. We tested respiratory specimens for respiratory syncytial virus, parainfluenza viruses, human metapneumovirus, influenza, adenovirus and rhinoviruses using rRT-PCR. During 2013, we conducted a health utilization survey in the primary catchment areas of the hospitals to determine the proportion of all hospitalizations for respiratory illness among children aged <5 years at the surveillance hospitals during the preceding 12 months. We estimated the respiratory virus-specific incidence of hospitalization by dividing the estimated number of hospitalized children with a laboratory confirmed infection with a respiratory virus by the population aged <5 years of the catchment areas and adjusted for the proportion of children who were hospitalized at the surveillance hospitals. RESULTS: We estimated that the annual incidence per 1000 children (95% CI) of all cause associated respiratory hospitalization was 11.5 (10-12). The incidences per 1000 children (95% CI) per year for respiratory syncytial virus, parainfluenza, adenovirus, human metapneumovirus and influenza infections were 3(2-3), 0.5(0.4-0.8), 0.4 (0.3-0.6), 0.4 (0.3-0.6), and 0.4 (0.3-0.6) respectively. The incidences per 1000 children (95%CI) of rhinovirus-associated infections among hospitalized children were 5 (3-7), 2 (1-3), 1 (0.6-2), and 3 (2-4) in 2010, 2011, 2012 and 2013, respectively. CONCLUSION: Our data suggest that respiratory viruses are associated with a substantial burden of hospitalization in children aged <5 years in Bangladesh.

Raw Sap Consumption Habits and Its Association with Knowledge of Nipah Virus in Two Endemic Districts in Bangladesh.

Human Nipah virus (NiV) infection in Bangladesh is a fatal disease that can be transmitted from bats to humans who drink contaminated raw date palm sap collected overnight during the cold season. Our study aimed to understand date palm sap consumption habits of rural residents and factors associated with consumption. In November-December 2012 the field team interviewed adult respondents from randomly selected villages from Rajbari and Kushtia Districts in Bangladesh. We calculated the proportion of people who consumed raw sap and had heard about a disease from raw sap consumption. We assessed the factors associated with raw sap consumption by calculating prevalence ratios (PR) adjusted for village level clustering effects. Among the 1,777 respondents interviewed, half (50%) reported drinking raw sap during the previous sap collection season and 37% consumed raw sap at least once per month. Few respondents (5%) heard about NiV. Thirty-seven percent of respondents reported hearing about a disease transmitted through raw sap consumption, inclusive of a 10% who related it with milder illness like diarrhea, vomiting or indigestion rather than NiV. Respondents who harvested date palm trees in their household were more likely to drink sap than those who did not own date palm trees (79% vs. 65% PR 1.2, 95% CI 1.1-1.3, p<0.001). When sap was available, respondents who heard about a disease from raw sap consumption were just as likely to drink it as those who did not hear about a disease (69% vs. 67%, PR 1.0, 95% CI 0.9-1.1, p = 0.512). Respondents' knowledge of NiV was low. They might not have properly understood the risk of NiV, and were likely to drink sap when it was available. Implementing strategies to increase awareness about the risks of NiV and protect sap from bats might reduce the risk of NiV transmission.