Scientists say they have discovered that the Covid-19 virus has mutated 30 times with the deadlier strain infecting Europe.
Researchers from Zhejiang University in China say the killer virus has evolved into multiple different strains since it jumped from animals to humans in December.
And they claim that the most lethal strains are the ones that are rapidly spreading throughout Europe. Shocking new figures reveal that the UK’s coronavirus death toll could be 40 per cent higher than has been reported.
The authors say their findings are the first to reveal how the mutation could affect the severity of the disease.
Scientists believe the virus – known as Sars-CoV-2 – is constantly mutating to overcome immune system resistance in different populations.
The researchers made their revelation after assessing viral strains from 11 Chinese coronavirus patients.
The team, led by Professor Li Lanjuan, tested how effectively the virus could infect and kill human cells in the laboratory.
The amount of the virus, dubbed by experts as the viral load, was analysed in all the cells after one, two, four and eight hours, as well as the next day and 48 hours later.
And the experts also explored whether the virus structurally changed the cell during infection, known as the cytopathic effects, up to three days after the experiment.
They found that the most aggressive strains created up to 270 times as much viral load as the least deadly type.
And Professor Li and her team revealed that the strains that produced the highest viral load led to a “higher cell death ratio”.
Writing in the study, which is published on medRxiv.org, the team said: “Our results show the observed mutations can have a direct impact on the viral load and CPE.
“This finding suggests the observed mutations in our study… can significantly impact the pathogenicity (the ability to cause disease) of SARS-CoV-2.”
The scientists found some of the deadliest mutations in Zhejiang, where the university is located.
These strains had also been seen in several hard-hit European countries such as Italy and Spain – before spreading to the US epicentre New York.
Despite this, the researchers pointed out that the “full mutational diversity of the virus in Wuhan in the early days is still unknown”.
The scientists discovered about 30 strains in total and about 60 percent of them, or 19, were new.
Professor Ian Jones, Professor of Virology, University of Reading, said that it was “not surprising” that the new study revealed mutations had an effect on the virus’ properties.
He said: “Coronaviruses generate mutations as part of their normal replication. That some of these would have an effect on virus properties is not surprising.
“However, this is a lab study, a description of possibilities, it does not address how the virus moves in the human population where many factors, usually summed up as virus “fitness”, apply at the same time.
“Rather than get distracted with potential mutants we should remain focused on detection and treatment of the virus as we find it now.
“At our cost the virus is doing well enough colonising the human population, I don’t see the drive for it to get nastier anytime soon. “