A new Covid variant called C.1.2 has been detected in South Africa, triggering a wave of alarm around the world.
The National Institute for Communicable Diseases (NICD) in South Africa issued an alert about the strain on Monday. It said said a “very low” rate of the mutation had been detected in all provinces across the country and within several other countries, including the UK.
NICD explained C.1.2 “has since been detected across the majority of the provinces in South Africa and in seven other countries spanning Africa, Europe, Asia and Oceania”.
The new variant has been present since May, but the Delta variant is still the most dominant strain around the globe. So why are scientists interested in this strain – and is it a cause for concern?
C.1.2 mutated almost twice as fast as other variants
The strain is said to contain similar mutations within its genome to those of other variants of concern including the Alpha, Beta, Gamma and Delta strains – along with some extra mutations. It has also mutated almost twice as fast as other global variants.
As Dr Megan Steain of the University of Sydney told The Guardian: “It contains quite a few key mutations that we see in other variants that have gone to become variants of interest or concern.”
She added: “While we can say that it has a few key mutations that have led to other variants being more infectious, often what we find is the mutations work in synergy together which can overall lead to a fitter virus, potentially, or a weaker virus.”
A fitter virus refers to a variant which has gained advantageous mutations which allow it to enter cells more efficiently, and begin an infection at a faster rate. Fitter viruses can usually reproduce at a faster rate too.
Why the WHO aren’t worried just yet
Having more mutations does not mean it is necessarily more dangerous – the alterations could make it both weaker or stronger.
C.1.2 has not yet been listed as a variant of concern or interest with the World Health Organisation (WHO) because the tests to understand the variant’s infectiousness and resistance to vaccines are still underway.
Variants of concern – such as Delta – show increased transmissibility, virulence or a significant change in clinical disease. Public health measures are less effective against them compared to ancestral strains.
Variants of interest refer to those which cause community transmission in multiple clusters across several countries, but are yet to be proven to be more virulent or transmissible.
As the WHO has not categorised the new strain yet, it does not have a Greek letter of the alphabet assigned to it.
The variant could die off
Covid variants often appear and then die out before posing a real problem to the pandemic. Only a handful of key mutant ones – such as the Delta variant – survive and grow.
Technical lead on Covid for WHO, Maria van Kerkhove, also pointed out that very few people who tested positive have been infected with this particular variant, despite it being present since May.
She tweeted: “To date there are around 100 sequences of C.1.2 reported globally, the earliest reports from May ’21 from South Africa.”
She pointed out that it does not seem to be increasing in circulation, unlike the Alpha and Delta variants which spread rapidly around the world. Its frequency remains low – although it has increased from being in 0.2% of genomes compared to 2%.
Will the vaccine still fight it off?
Dr Steain said: “We’ve got to bear in mind that the vaccine so far looks like it’s holding up really, really well in terms of preventing severe infection and hospitalisation and deaths from variants. They’re really good at preventing that.”
South Africa’s National Institute for Communicable Diseases told The Guardian: “We are being cautious about the implications while we gather more data to understand virus of this lineage.
“Because on our understanding of the mutations in this variant, we suspect that it might be able to partially evade the immune response, but despite this, that vaccines will still offer high levels of protection against hospitalisation and death.”
NCID researcher Penny Moore also said: “We have considerable confidence that the vaccines that are being rolled out in South Africa will continue to protect us against severe illness and death.”