Question to the Department of Health and Social Care:

To ask Her Majesty's Government whether they will publish the latest evidence base which has led to the B1.351 COVID-19 variant being categorised as a variant of concern, particularly in regard to its transmissibility.

The B.1.351 COVID-19 variant was categorised as a variant of concern (VOC) on 23 December 2020 by the New and Emerging Respiratory Virus Threats Advisory Group. The decision to raise this lineage to a VOC was taken on the basis of reports indicating that the strain had replaced pre-existing strains in parts of South Africa and that there were two cases of B.1.351 identified in the United Kingdom with links to travel from South Africa. The genetic variations identified in the spike protein of B.1.351 were also cause for concern.

The three substitutions in the receptor binding domain, and in particular the E484K substitution, were thought to result in weaker neutralisation by some monoclonal antibodies and polyclonal neutralising sera. Although at the time there was no formal modelling from South Africa, the rapid spread of the variant could be consistent with increased transmissibility, which was also biologically plausible. More recent data has shown that B.1.351 has greater transmissibility than the original Wuhan strains of the virus. Evaluation was at an early stage when the recommendation to escalate this lineage was taken. A copy of PHE Risk assessment for SARS-CoV-2 variant: VOC-202012/02 (origin: South Africa) of 23 December is attached.