The strange variation of Covid-19 detected in Magellan that intrigues scientists

The virus that causes Covid-19 disease shows many variations. And along with its propagation and with the advancement of the months, its different strains or variants also evolve. These are the so-called mutations that, in Chile, according to a recent study, has a particularity in the extreme south of the territory: an eventual new strain of the coronavirus in the Magallanes Region.

The region was one of the first to report the highest number of infections on April 11, with 50 infections. On October 1, 132 infected were reported and a positivity of 33%.

By sequencing the genome of clinical strains in the area, researchers from the Research Teaching Assistance Center of the Magallanes University, identified that the strain of the cases of the months of May and June were different from those that occurred in the following months. The difference? In July, a greater presence of clade 20B or lineage of the SARS-CoV-2 virus in the population.

Analysis of the virus genome during the spread of the disease reveals its evolution and transmission, explains Marcelo Navarrete, director of the Research Teaching Assistance Center of the University of Magallanes. The researcher asks to be cautious with the results of the investigation, “a study that is still in development, they are preliminary results and that were communicated to the authorities.”

On Saturday, October 3, at the delivery of the Covid-19 report, the Minister of Health, Enrique Paris, named the study and the detection of a variant of coronavirus in Magallanes in the second wave of the outbreak of infections.

The Undersecretary of Health Paula Daza, for his part, he pointed out that the study is being evaluated, “if there is any mutation in the virus, if it is a new virus, if it is the same virus, if this was a reintroduction; there are a series of measures that are being evaluated to see what is happening ”.

The clades or main lineages of the virus are named for the year in which they are estimated to have emerged and a letter. Each clade is at least 2 mutations away from its parent clade. Thus, for example, Sars-CoV-2 lineages have been named 19A, 19B, 20A. The one detected in Magallanes corresponds to 20B.

What the research team has studied is how the virus genome has changed over time in the region. The variants that constituted the dominant viruses during the months of May and June, Navarrete explains, tended to disappear in the following months. “In those months we achieved adequate control of the pandemic, but then in the following months there is an explosion of cases and what we saw that the variants did not follow the evolutionary line of the previous wave from a genetic perspective”, He details.

A work resulting from more than three months of local monitoring of the behavior of SARS-CoV-2 and that stands out for its contribution to regional scientific research. “It is important that there is development in the regions. The local capacity is essential to identify and observe the phenomena that affect us, and not being dependent on other centers ”, indicates Navarrete.

That lineage, although it is present in the rest of the world, is found in a low frequency. “That genome is described elsewhere, but very little and for some reason he found a niche in this region”, Maintains Navarrete. It belongs to category 20B and diverges within that group, he adds, “and is sporadically described in Italy, Spain.”

Just as the 20A lineage corresponds to the one that dominated the great European outbreak in early 2020. The 20B is another European clade that in turn presents several consecutive mutations.

Does this variety contribute to greater contagion? Navarrete emphasizes that in the current state of the investigation “it is not known if it would contribute to greater contagion.” What is known, he indicates, is that it has the characteristic of having a mutation in the protein spike that responsible for the adherence of the virus to the body. “Currently with a group of experts in structural modeling we are seeing the potential effects it would have, but it is a matter of research,” he clarifies.

“So far we do not know what factors facilitate its high frequency here, it is not known whether it can be expanded to the rest of the country,” says the researcher about the results of the investigation. Currently, he says, the study manuscript is being prepared and “First you have to do experiments to confirm these hypotheses.”

Nicolás Muena, researcher at the Science and Life Foundation, indicates that this genomic surveillance must always be done, to find out if these variations could give Covid-19 any advantage, such as making it more infectious, for example.

About clade 20B, says Muena, it is known that the first isolates were detected in Western Europe, “it seems that the mutation occurred there and it became more frequent over time, for example, in Russia has become the predominant variant, and the variant before was the 20A”.

Know at this time if it will expand to the rest of the country, says Muena, it is not simple to determine. “It is difficult to give an answer to that, because this is being very dynamic so it is difficult to predict whether it will be more frequent in the country or not.”

For example, in India, says Muena, there are some parts in which 20A predominates and in others 20 B. “It is difficult to predict, because we do not know if Magellan’s is classic 20B or if there are mutations in spike or if it will be a new one that can give the virus an advantage such as greater stability or infectivity. “Most of the variations, he adds, does not grant you evade the immune system, “It is much less frequent that the coronavirus achieves that because they have a correction mechanism for these mutations and those mutations are slow, the coronavirus makes mistakes less than other viruses thanks to that.”

Identifying these variations is progress, says Navarrete, but “one is concerned that this evidence is used as an excuse to relax measures in the population, the only measures are distancing measures, it is important that all people, especially in the region, continue to maintain social distancing and use a mask ”.