A Covid 19 variant first detected in Africa is being watched closely by scientists - with one UK virologist warning it may be the worst strain yet.

The variant emerging in Botswana, currently named B.1.1.529, which has since spread to Hong Kong and South Africa, is believed to be the most mutated strain so far, leaving experts to question what impact vaccines and antibodies will have on it.

To date only a small number of cases of the strain have been officially identified by geonomic sequencing, none of them in the UK, with the majority either originating in Africa or which can be traced back to travel through the continent.

But investigations have found that the B.1.1.529 strain has 32 mutations to its spike protein - the part of the virus the majority of vaccines use to prime the immune system against Covid 19 - leaving experts to question the risk it might pose to vaccines if it were to continue to spread.

Dr Tom Peacock, a virologist at the Department of Infectious Disease based at Imperial College London, posted details about the new variant on Twitter warning that its 'horrific' spike profile means it should be closely watched.

In a series of tweets he wrote: "Worth emphasising this is at super low numbers right now in a region of Africa that is fairly well sampled, however it very very much should be monitored due to that horrific spike profile (would take a guess that this would be worse antigenically than nearly anything else about."

As a result of geonomic sequencing, which looks at the genetic make up of positive covid tests to identify new variants or mutations in circulation, scientists often identify strains of the virus that never grow to be any more than a small number of cases.

However with a successful vaccination programme worldwide thought to be the solution to all countries eventually emerging from the pandemic and ongoing restrictions, virologists are quick to track any new strains that emerge causing concern.

Earlier this week the government changed its advice for Covid testing in the UK as it attempts to avoid the fourth wave of the virus Western Europe is now experiencing, which has forced many countries to return to either full or partial lockdowns and debate mandatory vaccination policies.

Previous advice for people to take twice-weekly lateral flow tests or when visiting someone medically vulnerable has been updated with guidance to also test when entering busy 'high-risk' crowded areas this winter.