COVID-19: Is the new coronavirus mutation worse than first thought?

A new variant of COVID-19 in the UK that is believed to be behind the faster spread of infections in southeast England has been described as “a real cause for concern”.

But it is not the first time the virus had mutated since the start of the pandemic and it may not even be the first time a mutation – or a change in the virus’ genetic material – has altered how infectious it is.

So, what do we know about it so far?

Is it more transmissible?

Yes. It seems so. Prime Minister Boris Johnson said the new variant strain, VUI-202012/01, may be up to 70% more transmissible and could increase the R number by 0.4.

The latest figures suggest that this strain is responsible for 43% of new infections in the South East – rising to 59% of new cases in the East of England and 62% in London.

Professor Chris Whitty, England’s chief medical officer, said: “Those have gone up very, very fast over the last few weeks.”

Sir Patrick Vallance, the chief scientific adviser, added that “an unusually large number of variants” – 23 different changes – have been identified with this new strain.

Following preliminary modelling data and rapidly rising incidence rates in the South East, the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG) now agrees that the new strain could spread more quickly.

Professor Whitty said he had alerted the World Health Organisation to its existence – and would be concentrating on analysing data related to the mutation’s spread.

As he announced the introduction of Tier 4 restrictions for large swathes of London and the South East, Boris Johnson told the country: “When the science changes, we must change our response.

“When the virus changes its methods of attack we must change our method of defence – and as your prime minister, I sincerely believe there is no alternative open to me.”

Professor Whitty urged people not to travel outside these areas, as there was a “significant risk” of passing it on.

Does it make people more ill?

Professor Whitty said there was “no current evidence to suggest the new strain causes a higher mortality rate or that it affects vaccines and treatments”, but work was under way to confirm this.

However, Jeremy Farrar, director of the Wellcome Trust, a medical research charity, said in a tweet, that its existence was still “worrying and a real cause for concern”.

He added: “Research is ongoing to understand more, but acting urgently now is critical. There is no part of the UK and globally that should not be concerned. As in many countries, the situation is fragile.”

Does the new strain respond to the vaccine?

The COVID-19 Genomics UK (COG-UK) consortium said it is difficult to predict whether any given mutation is important when it first emerges, but agreed that the biggest concern was any changes that lead to an increase in reinfections or vaccine failure.

But Professor Whitty said that, as of now, there was no evidence to suggest the new strain affected vaccines and treatments.

He added “urgent work” was under way to confirm this and warned that it was “more vital than ever” that people continued to take action to reduce the spread of the virus.

So far, experts have not found any variants that could make a vaccine less effective, and the virus has been slow to mutate.

Professor Whitty said it would be “surprising” if it had an effect on the vaccine.

Federico Giorgi, a researcher at the University of Bologna who co-ordinated a study into strains of COVID-19, told Science Daily: “The SARS-CoV-2 coronavirus is presumably already optimised to affect human beings, and this explains its low evolutionary change.

“This means that the treatments we are developing, including a vaccine, might be effective against all the virus strains.”

What are the different strains?

So far, there have been at least seven major groups, or strains, of COVID-19 as it adapts to its human hosts.

The original strain, discovered in the Chinese city of Wuhan in December last year, is known as the L strain.

It then mutated into the S strain at the beginning of 2020, before being followed by the V and G strains.

Strain G has been most commonly found in Europe and North America – but because these continents were slow to restrict movement, it allowed the virus to spread faster and therefore mutate further into strains GR, GH and GV.

Meanwhile, the original L strain persisted for longer in Asia because several countries – including China – were quick to shut their borders and stop movement.

Several other less frequent mutations are grouped together as strain O.

In Denmark, authorities became worried about a strain of the virus found in 12 people related to mink farming.

They feared the mutation could hamper the effectiveness of a vaccine because it had happened in the spike protein, and as a result the government ordered a mass cull of up to 17 million animals and a month-long lockdown for people living in the northwest of the country.

What are the most common strains around the world?

G strains are now dominant around the world, particularly in Italy and Europe, coinciding with spikes in outbreaks.

A specific mutation, D614G, is the most common variant. Some experts say this variation has made the virus more infectious, but other studies have contradicted this.

Meanwhile, earlier strains such as the original L strain and the V strain are gradually disappearing.

Analysis by the Reuters news agency shows that Australia’s quick reaction to the pandemic and effective social distancing measures have eliminated transmission of the earlier L and S strains in the country, and that new infections are the result of G strains brought in from overseas.

In Asia, the strains G, GH and GR have been increasing since the beginning of March, more than a month after they started spreading in Europe.

(c) Sky News 2020: COVID-19: Is the new coronavirus mutation worse than first thought?