The emergence in the United Kingdom of a new strain of coronavirus, presented as more contagious than the others, has caused great concern in Europe. But nothing seems to indicate that this variant causes more severe forms of the disease or that it is resistant to vaccines, say experts.
Is it normal for the virus to move?
Viruses, as living things, are endowed with genetic material (DNA or RNA), which can be subject to change when they replicate (mutations) in the cells in which they spread or through exchanges between viruses (recombination). In general, this usually has no consequences, but mutations can also give the virus an advantage or a disadvantage for its survival.
“There are certainly thousands of options,” said Emma Hodcroft, an epidemiologist at the University of Bern.
“The most important thing is to try to know if this variant has properties with an impact on human health, diagnosis and vaccines,” said Julian Hiscox, a professor of infectology at the University of Liverpool, quoted by the Science Media Center.
The new strain, which prompted the British government to sound the alarm, carries a mutation, called “N501Y”, in the spike protein of the coronavirus, with which the virus attaches to human cells enters them.
Is this variant more contagious?
According to British Prime Minister Boris Johnson, this strain could be up to 70% more contagious, causing many European countries and the rest of the world to suspend air and rail links with the United Kingdom.
“The UK has seen a rapid increase in the number of cases of covid-19 in the south-east of England in recent weeks” and analyzes show that “a large proportion of cases belonged” to the new mutation in the virus, the report said. Sunday European Center for Disease Prevention and Control (ECDC).
“The reasons for this increase in infectivity are still unclear. We have not yet found out whether it is due to increased viral replication or a better connection to the cells that cover the nose and lungs,” said Peter Openshaw, a professor of experimental medicine. Imperial College London, Science Media Center.
For her part, Emma Hodcroft was cautious about saying that the virus could be “70% more contagious”, because when estimates are made too early, they can change. “We don’t know much about where this figure came from,” he warned.
In addition, in that region of south-east England, “the group’s immunity in the population is weak and the virus has found ground to develop,” the deputy director of the National Reference Center for Respiratory Viruses at the Pasteur Institute told AFP. Paris, Vincent Enouf.
How did this strain circulate?
It is difficult to say that this new form was born in the United Kingdom. That country “is the world leader in sequencing […]. So if there is a variant and it comes to the UK, there is a good chance it will detect it, “said Emma Hodcroft. According to her, the first sequence of this new strain dates from September.
According to the World Health Organization (WHO), similar forms have been detected in several countries, such as Australia (one case), Denmark (9), the Netherlands (1) and South Africa. Italy also announced that it had detected a first case on Sunday.
“Although he was not born in the United Kingdom, he seems to have grown up there in England,” said Emma Hodcroft.
– Will the vaccine be less effective?
At this time, scientists consider it unlikely that this new strain will be resistant to current covid-19 vaccines.
“The idea of the vaccine is to show the whole Spike protein to the immune system, which in this way learns to recognize its many parts,” explained Emma Hodcroft. Thus, “although some parts change, the rest of the parties remain to recognize” the virus, he said.
Vincent Enouf said that “a repertoire of antibodies should be enough”.
“At this time, there is no indication that this new strain has a higher mortality rate or affects vaccines and treatments, but urgent work is being done to confirm this,” added England’s chief physician Chris Whitty. WHO and ECDC have reached the same conclusion.
Will it affect the tests?
“Those responsible for the laboratories should check with their suppliers if their tests could be defective” for this new variant, Vincent Enouf stressed.
According to the ECDC, the Spike protein change has caused negative results in some UK testing labs, which rely solely on that protein in their analyzes.