Viruses constantly change through mutation, and so the emergence of new variants is an expected occurrence and not in itself a cause for concern; SARS-CoV-2 is no exception. A diversification of SARS-CoV-2 due to evolution and adaptation processes has been observed globally.
While most emerging mutations will not have a significant impact on the spread of the virus, some mutations or combinations of mutations may provide the virus with a selective advantage, such as increased transmissibility or the ability to evade the host immune response. In such cases, these variants could increase the risk to human health and are considered to be variants of concern.
New variants of current concern
The United Kingdom (UK) has faced a rapid increase in COVID-19 case rates in the South-East, the East and the London area, which is associated with the emergence of a new SARS-CoV-2 variant, VOC 202012/01. As of 26 December 2020, more than 3 000 cases of this new variant, confirmed by genome sequencing, have been reported from the UK. An increasing proportion of cases in the South East, the East and the London area are due to this variant, but cases have also been identified in other parts of the UK. Although it was first reported in early December, the initial cases were retrospectively identified as having emerged in late September. Preliminary analyses indicate that the new variant has increased transmissibility compared to previously circulating variants, but no increase in infection severity has so far been identified. Since 26 December, a few VOC 202012/01 cases have also been reported in other EU/EEA countries (Belgium, Denmark, Finland, France, Germany, Iceland, Ireland, Italy, the Netherlands, Norway, Portugal, Spain and Sweden) and globally (Australia, Canada, Hong Kong SAR, India, Israel, Japan, Jordan, Lebanon, South Korea, Switzerland, Singapore). In addition to VOC 202012/01, South Africa has reported another SARS-CoV-2 variant, designated as 501.V2, which is also of potential concern. This variant was first observed in samples from October, and since then more than 300 cases with the 501.V2 variant have been confirmed by whole genome sequencing (WGS) in South Africa, where it is now the dominant form of the virus. Preliminary results indicate that this variant may have an increased transmissibility. However, like the VOC 202012/01, at this stage there is no evidence that 501.V2 is associated with higher severity of infection. On 22 December 2020, two geographically separate cases of this new variant 501.V2 were detected in the UK. Both are contacts of symptomatic individuals returning from travel to South Africa. On 28 December 2020, one additional case of this new variant was detected in Finland in a returning traveller from South Africa.
- Europe
- risk assessment
- COVID-19
