Abstract

Kristian D Stensland

In recent weeks, several new strains of SARS-CoV-2, the causative agent of COVID-19, have emerged. These variants have evolved an increased transmission rate compared to the original strains, which makes controlling this virus even more challenging. What has happened, and how do we best respond now? One strain-UK lineage (variant of concern 202012/1) in particular is currently sweeping the UK. A recent report has suggested that this strain has a significantly higher potential rate of transmission (R0) compared to previous variants. Genomic analysis of the strain found substantial novel sequence variation caused by mutations, which may provide a biological reason for the observed increase in transmissibility. Initial assessments suggest the novel variants show an improved interaction with host cell receptors, such as ACE2 on epithelial cells. This enables the virus to better establish and propagate infections, resulting in higher levels of virus in the host and increased rate of transmission.