The SARS-CoV-2 coronavirus, which causes the covid-19 pandemic, has hundreds of mutations, but one of the most present in the second wave that lives in Europe occurred first in Spain, Spanish and Swiss scientists conclude in a study released today.
Analyzes carried out by the University of Basel, the Federal Polytechnic School of Zurich and the Spanish consortium SeqCovid-Spain, led by the Higher Council for Scientific Research, show that the new variant has spread to Europe and other regions in recent months from Spain.
The easing of travel restrictions in the summer and the fact that Spain is an important tourist destination have facilitated the expansion of this variant of the virus genome, according to a statement from the University of Basel.
"In Europe alone, there are hundreds of variants of the new coronavirus circulating, with mutations in the genomes, but very few have spread so successfully and have been as persistent as this one," according to information released by the center.
The researchers said that the emergence in Spain, during the summer months, may be linked to an “overprogator event linked to agricultural workers in northwest Spain” and that has spread throughout Spain and a dozen European countries.
The experts named this mutation “20A.EU1” and the tests detected it in about 80% of the samples analyzed in Spain, about 90% in the United Kingdom and between 30% and 40% of those studied in Switzerland and the Netherlands.
It was also found in samples from France, Belgium, Germany, Italy, Latvia, Norway and Sweden and even outside Europe, in case analyzes recorded in Hong Kong and New Zealand.
Basel University professor Emma Hodcroft, the study's lead author, argued that there is no indication that this variant of the coronavirus is more contagious than the others, but that its transmission could be due to a slowdown in preventive measures in the summer.
Colleague Iñaki Comas, co-author of the study and director of SeqCovid-Spain, added that the lines of this mutation are similar to others identified in previous studies, during the spring.
"A variant [of the virus], helped by a super propagating event, can quickly prevail across an entire country," said Comas, quoted in the statement from the Swiss university.
The experts warned that there is no indication that the identified variant is more dangerous than the others or that it behaves differently, or even that it is the only one prevalent in the second European wave, in which other mutations have been identified.
They also asked for caution when directly linking the mutation to the strong increase in cases in Europe and stressed that in some countries on the continent that now have alarming rates of contagion, such as France or Belgium, this is not the predominant variation.
They did insist that the discovery could provide more information on the effectiveness of transport policies implemented by European countries this summer, after the reduction of cases from the first wave.
"The closing of long-term borders and strong restrictions on travel are not desirable, but with the expansion of 20A.EU1 it seems clear that the measures taken were insufficient to stop the contagion of new variants," concluded Hodcroft.
The mutation was first detected in sequence analyzes carried out in Switzerland, using the Nextstrain platform, developed by the University of Basel and the Fred Hutchinson Cancer Research Center, Seattle (EEUU).
This platform, created in 2015, allows real-time screening of pathogens through genetic sequencing, and has been used previously to analyze the expansion of viruses such as Zika, Ebola and influenza.
The Swiss Hispanic study has not yet been published in scientific journals, but it was on the specialized network medRxiv, an archive of medical manuscripts not yet reviewed by other scientists, which is linked to the American Univers.