The Epsilon variant is more resistant to antibodies, both those generated by mRna vaccines and following infection with Covid-19. Isolated in California, it is already spreading to the rest of the world. This is why a vigilant sequencing activity is urgently needed to control its trajectory
Here is a new variant. After Delta and Gamma now we talk about the Epsilon. It is now clear to everyone that one of the peculiarities of this virus is the continuous remodeling. The longer it stays in circulation, the more likely you are to face new variations. This was revealed by a new study from the University of Washington, coordinated by Matthew McCollum and published in Science. The mutations, named B.1.427 and B.1.429, were first detected in California in early 2021. In May, they appeared in 34 countries, suggesting a noteworthy spreading capacity. Epsilon has had little propagation in Europe for the time being. However, what worries the scientific community is the superior resistance to antibodies, highlighted in studies conducted by the University.
THE DIFFUSION OF THE VARIANT
Currently, this mutation is predominant in California, the place from which the origin is hypothesized. According to data reported by Gisaid, 12 countries of the Old Continent have welcomed the virus. Belgium, Denmark, France, Finland, Germany, Ireland, Italy, Norway, Holland, Spain, Switzerland, Sweden, are all nations that currently have fewer than 40 cases. In the rest of the world, on the other hand, in the last four weeks, Epsilon has been present in 44 countries, with particular interest in South Korea, Japan, India and the United States.
In Italy there are only two cases at the moment. In any case, this would prove to be the perfect opportunity, given the negligible number of infections, to modulate an effective plan for tracking individuals, in order to be able to immediately sequence the genome and isolate the variant. This would certainly avoid a possible epsilon wave in our country, a possible hypothesis also due to its antibody resistance.
I STUDY
According to studies conducted by McCollum, the Epsilon variant has a higher antibody resistance than the variants already known. In fact, Epsilon has three mutations of the spike protein, which is the part that allows the virus to penetrate into the cells of our body. This characteristic confers greater resistance to neutralizing antibodies generated by mRNA vaccines or by previous Covid 19 infection. The following statements were made possible thanks to the analysis of blood plasma, carried out on a small pool of 54 individuals.
As regards the resistance to the messenger RNA vaccine, the penetration capacity of the virus was noted in 15 people vaccinated with Moderna and 33 with Pfizer, all of whom have already received full and not partial administrations. On the other hand, 9 individuals previously infected with Covid-19 have shown traces of the variant in their blood plasma.
ANTIBODY RESISTANCE AND SEQUENCING
The major antibody resistance focuses primarily on the L452R spike protein mutation. As pointed out by Science there is the acquisition of the L452R mutation by multiple lineages in multiple continents, including the Indian variant, known as B.1.617.1 and B.1.617.2. However, we must also count another section of the spike protein, namely the N-terminal domain (NTD), which is subject to rapid antigenic drift and accumulates a greater number of mutations than other regions of the spike protein.
The resulting mapping of NTD suggests that NTD is subject to severe selective pressure from the host organism’s humoral immune response. From this discovery, it derives a lower ability to neutralize Covid-19 by antibodies, especially for immuno-compromised patients and those who have already been infected previously. Science has placed strong attention on this new mechanism, explaining how this new method of immune evasion should lead to an intense and vigilant sequencing activity to control the trajectory of this new variant.