The reason why new strain of COVID is up to 70% more transmissible

A leading scientist has revealed why the new strain of coronavirus is up to 70% more transmissible than the original.

Prof Robert Dingwall sits on the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag) which has been advising England’s chief medical officer Prof Chris Whitty.

He said he believes the new strain is more transmissible because those who contract it produce more of the infection in their nose and mouth, meaning they will breathe more of it into the air.

“My understanding of it is that you are producing more of the infection in the upper respiratory tract and the virus is reproducing faster, so that there is more to go into the air to pass from one person to another,” the leading medical sociologist said on Tuesday.

“It doesn’t travel further, but having produced more it also has properties that make it easier to take over cells in person that it enters into.”

It comes as the latest available seven-day infection data showed nine areas of England now have more than 1,000 COVID cases per 100,000 people.

Genomic researchers also said on Tuesday that the new and more infectious variant has already spread around the UK, with cases identified in Wales and Scotland.

The COVID-19 Genomics UK (COG-UK) consortium sampled cases around the UK and found the variant is also in the South West, Midlands and North of England – areas that are under Tier 2 and 3 restrictions.

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Jeffrey Barrett, lead statistical geneticist at COG-UK, warned there was a lag in the sequence data being sampled, so the most recent data was from the first week of December when England came out of the second national lockdown.

At a Science Media Centre briefing on Tuesday, he said: "They're relatively small numbers but I think it is important to be aware that it is certainly not the case that this is just completely geographically constrained to what is the current Tier 4 area."

Dr Barrett said more up-to-date data from community testing also found one of the mutations of this variant.

Watch: New Tier 4 measures announced after rapid emergence of new strain

He said: "It shows essentially the same picture, that the variant is present in very many different places in England.

"It is certainly not isolated in one place, it has begun to spread to many places in England."

On Saturday, the new strain led to London and parts of southern and eastern England being rushed into the new Tier 4, while plans to ease curbs over Christmas across the UK were dramatically scaled back.

Many countries have also closed their borders to Britain due to concerns over the mutated strain of the virus.

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