COVID-19 rise in Bangladesh correlates with increasing detection of B.1.351 variant.

Epidemiological, phenotypic and genomic characterisation of certain variants of SARS-CoV-2 have highlighted the changing transmissibility, infectivity and antigenic escape capability of this virus. Of considerable interest are the B.1.1.7 variant (20I/501Y.V1)1 and B.1.351 variant (20H/501Y.V2)2 that have now been reported from multiple countries around the world. B.1.1.7 was first detected in September 2020 in the UK through genomic surveillance, and it contains a mutation (N501Y) in the receptor-binding domain of the spike protein that has been reported to increase transmission1 and virulence3 through genomic and epidemiological studies. The variant still shows strong response to antibody treatment and is effectively neutralised by antibodies generated on vaccination by mRNA-based vaccines.4 The B.1.351, first identified in South Africa in October 2020,2 carries the N501Y mutation and two additional mutations (E484K and K471N) that confer increased antibody resistance.4 These findings make it imperative to continuously track circulating variants of SARS-CoV-2 globally, especially in low-resource settings, to institute evidence-based policy decisions. This editorial aims to raise awareness regarding the increasing isolation of the B.1.1.7 and B.1.351 variants and documented cases of re-infection in Bangladesh in recent months. Bangladesh, one of the most densely populated countries of the world, detected the first SARS-CoV-2 cases on 8 March 2020. Immediately following that, non-pharmaceutical interventions including school closures, work from home mandate and flight bans were instituted for the following 2 months (figure 1A). After the first peak in July 2020 (3810 cases/day, 7-day average) case numbers reduced, with a slight surge in December 2020 (2185 cases/day, 7-day average) that also subsided.5 A small study conducted in July of 2020 estimated that seroprevalence in Dhaka, the capital of Bangladesh, ranged from 45% to 74%.6 However, starting in early March 2021, case numbers began to rise rapidly, and the reproduction number …