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

Nazneen, Arifa; Sultana, Rebeca; Rahman, Mahmudur; Rahman, Mahbubur; Qadri, Firdausi; Rimi, Nadia Ali; Hossain, Md. Kamal; Alam, Muhammad Rashedul; Rahman, Mustafizur; Chakraborty, Nitai; Sumon, Shariful Amin; Hussain, Enayet; Hasan, Mohammad Zakiul; Khan, Sazzad Hossain; Prodhan, Md. Hasnatuzzaman; Bablu, Arifur Rahman; Banik, Kajal Chandra; Fahad, Md. Habibullah; Akhtar, Marjahan; Satter, Syed Moinuddin; Ahmed, Shahriar; Rahman, Ahmed Ehsanur; Bhuiyan, Taufiqur Rahman; Alamgir, A.S.M.; Arifeen, Shams El; Shirin, Tahmina; Banu, Sayera; Flora, Meerjady Sarbrina

Objective We aimed to estimate the proportion of symptomatic and asymptomatic laboratory-confirmed COVID-19 cases among Bangladesh's population. Design We conducted a cross-sectional survey in Dhaka City and other districts of Bangladesh between April 18 and October 12, 2020. We randomly selected 32 districts outside Dhaka, where one village and one mahalla from each district, and from Dhaka City, selected 25 mahallas. From each village or mahalla, we enrolled 120 households through systematic random sampling. Results A total of 44,865 individuals were interviewed from 10,907 households. The majority (70%, n-31488) of the individuals were <40 years of age. Almost half of the individuals (49%, n=21,888) reported >4 members in their households. We estimated, 12.6% (n=160) of the households had ≥1 COVID-19 infected individuals, among them, 0.9% (n=404) individuals had at least one COVID-19 like symptom at the national level. Prevalence of COVID-19 was 6.4% among the general population. Among the COVID-19 positive individuals, 87% were asymptomatic. Conclusions The substantial high number of asymptomatic cases all over Bangladesh suggests that community-level containment and mitigation measures to combat COVID-19. Future studies to understand the transmission capability could help to define mitigation and control measures.