Background Amid growing debate between scientists and policymakers on the trade-oﬀ between public safety and reviving economy during the COVID-19 pandemic, the government of Bangladesh decided to relax the countrywide lockdown restrictions from the beginning of June 2020. Instead, the Ministry of Public Aﬀairs oﬃcials have declared some parts of the capital city and a few other districts as red zones or high-risk areas based on the number of people infected in the late June 2020. Nonetheless, the COVID-19 infection rate had been increasing in almost every other part of the country. Ironically, rather than ensuring rapid tests and isolation of COVID-19 patients, from the beginning of July 2020, the Directorate General of Health Services restrained the maximum number of tests per laboratory. Thus, the health experts have raised the question of whether the government is heading toward achieving herd immunity instead of containing the COVID-19 pandemic.
Methods We propose an age-group clustering method to estimate the susceptible population and use the adjusted SIRD model with Unscented Kalman Filter to analyze the dynamics of COVID-19 transmission rate in Bangladesh.
Results Our analysis on the susceptible population distribution suggests that the key propagation agent is the young adult due to their socio-economic activities. We demonstrate that the herd immunity threshold can be reduced to 31% than that of 60% by considering age group cluster analysis resulting maximum 53.0 million susceptible populations in the lower middle income country. However, the case fatality rate (CFR) analysis shows that the most vulnerable people belong to the older population (> 60 years) in Bangladesh following the global trend. With the data of Covid-19 cases till July 22,2020, the time-varying reproduction numbers are used to explain the nature of the pandemic.
Conclusions Based on the estimations of active, severe, and critical cases, we discuss a set of policy recommendations to improve the current pandemic control methods in Bangladesh. Moreover, we suggest a fair trade-oﬀ between health versus the economy in order to avoid enormous death toll and to keep Bangladesh’s economy alive.