The coronavirus continues to mutate, with a (perhaps) more contagious strain

A new study confirms that the Sars-Cov-2 coronavirus has accumulated hundreds of mutations since the start of the pandemic, and will continue to do so. One may have made it more infectious (but not more serious)

(Photo: Fusion Medical Animation on Unsplash) The coronavirus is mutating and will continue to do so, because it is in its nature. The discovery of mutations in the original Sars-Cov-2 sequence has now been announced several times over the past few months, and now the largest peer reviewed study confirms it.

A team of US researchers analyzed the coronavirus genome in over 5,000 Covid-19 patients, identifying up to 285 points of difference from the original Wuhan virus. A natural process of genetic drift, experts say, driven by chance and in part promoted by the selective pressure of our immune system.

Most of these mutations, however, do not seem to have given the pathogen a particular advantage , although researchers continue to keep an eye on D614G which, by stabilizing the spike protein, may have made the virus more contagious, but no more deadly.

A more contagious strain, perhaps

Scientists analyzed Sars-Cov-2 genetic sequences in 5,085 patients between the first and second waves in the Houston metropolitan area, confirming that it is in most cases a different virus than the Wuhan original . Of the 285 identified differences, none apparently gave a particular advantage to the coronavirus.

The D614G alteration is an exception, which (as we have already told you here and here) may have made the pathogen more contagious.

The study, coordinated by researchers from the Houston Methodist Hospital (Austin, Texas, USA), confirms that when the virus with the D614G alteration made its appearance (and was introduced at different times and from different origins) ousted the other lines: in the first wave it was responsible for 71% of the infections analyzed, while in the second wave it was even 99.9%. A trend - the researchers write - that mirrors that in the rest of the world.

D614G involves the replacement of an amino acid in the spike protein: this change, according to several studies, could have improved it, increasing the capacity of the virus to attach to cells and infect them. However, neither previous research nor the investigations carried out by Texan researchers have linked the alteration to a greater danger of the coronavirus. In other words, being infected with this strain would not result in a more serious disease.

No vaccine problems, for now

The research, said Ilya Finkelstein of the University of Texas, aims to monitor the genetics of the coronavirus during the pandemic, so as not to risk having nasty surprises even on the front of the development of an effective vaccine.

It is not only the D614G alteration that is being addressed, note the author of the study: there is also a mutation still in the spike protein which from their preliminary experiments seems to give the virus the ability to evade a certain type of neutralizing antibodies that our organism produces as a result of infection.
Fortunately, however, the current differences in the genetic sequence of the virus do not appear to affect the potential efficacy of investigational vaccines. No viruses isolated from them, Finkelstein reported, have proven to be able to escape immune responses induced by first-generation vaccines or monoclonal antibody therapies.

“Real-time surveillance efforts, like our study, they will ensure that vaccines and global therapies are always one step ahead, "he concluded.