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. In this paper, the dynamics of the pandemic due to SARS-CoV-2 in Bangladesh is analyzed with integrated the Unscented Kalman Filter (UKF) in the SIRD model. We demonstrate that the herd immunity threshold can be reduced to 31% than that of 60% by considering age group cluster analysis resulting in a total of 53.0 million susceptible populations. With the data of COVID-19 cases till January, 2021, the time-varying reproduction numbers are used to explain the nature of the pandemic. 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.

中文翻译：

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由于孟加拉国的群体免疫，调整了 COVID-19 大流行的动态

在科学家和政策制定者之间就 COVID-19 大流行期间公共安全与经济复苏之间的权衡争论日益激烈之际，孟加拉国政府决定从 2020 年 6 月开始放宽全国范围内的封锁限制。取而代之的是，公共事务部根据 2020 年 6 月下旬的感染人数，官员已宣布首都的部分地区和其他一些地区为红区或高风险地区。尽管如此，几乎所有其他地区的 COVID-19 感染率都在上升国家的一部分。具有讽刺意味的是，从 2020 年 7 月开始，卫生服务总局并没有确保对 COVID-19 患者进行快速检测和隔离，而是限制了每个实验室的最大检测次数。因此，卫生专家提出了政府是否正朝着实现群体免疫而不是遏制 COVID-19 大流行的方向发展的问题。在本文中，通过在 SIRD 模型中集成无迹卡尔曼滤波器 (UKF) 分析了孟加拉国 SARS-CoV-2 引起的大流行动态。我们证明，通过考虑年龄组聚类分析，总共有 5300 万易感人群，群体免疫阈值可以从 60% 降低到 31%。使用截至 2021 年 1 月的 COVID-19 病例数据，使用随时间变化的繁殖数来解释大流行的性质。基于对活跃病例、重症病例和危重症病例的估计，我们讨论了一套政策建议，以改进孟加拉国目前的大流行控制方法。