Fiocruz identifies new variant of the coronavirus in the Amazon

Fiocruz do Amazonas has identified a new variant of the coronavirus that descends from omicron in the region, according to a note released last Saturday (12).

As a result of the rise in Covid cases in the state, especially in the capital, Fiocruz researchers analyzed more than 200 samples of the virus between September and October and found the new strain, according to a note from the institute.

The genomic sequencing of the virus samples that allowed the identification of the new lineage were collected by Fiocruz Amazônia in partnership with the Amazonas Health Surveillance Foundation and the state’s Lacen (Central Public Health Laboratory).

A new lineage of Sars-CoV-2, BA.5.3.1, had already been detected by researchers at the institute since June of this year.

The BE.9 variant regionally evolved from this lineage, as did another subvariant, BQ.1. Differently, it has at least three mutations in the gene that encodes the S protein (from “spike” or spike, the molecular hook used by the coronavirus to connect to human cells). One of these alterations is in the so-called receptor-binding region – something of concern because it is directly associated with the entry of the virus into cells.

This characteristic has not yet been identified in BQ.1 and may be advantageous for the virus by ensuring greater transmission from individual to individual.

In the last month, the state of Amazonas had a significant increase in the weekly moving average of cases, rising from 232, between October 9th and 15th, to 1,258 until last Saturday.

According to Felipe Naveca, researcher in public health at Fiocruz and responsible for sequencing and identifying the variant, BE.9 already corresponds to 94% of the samples sequenced in the region.

“What did we see [no Amazonas] it was a real increase in cases in the state and at the same time the presence of a lineage with mutations that increase the power of transmission and escape of the immune response, and which is already present in 94% of the samples. So we’re pretty safe saying she’s responsible for what’s going on,” he said.

Like BQ.1, BE.9 carries a mutation that can help it escape the action of antibodies, which would make the so-called vaccine escape cases – infections in fully vaccinated individuals – more common.

“We still don’t know what the magnitude of the new wave will be, if it will be a ‘wall’, as it was with the omicron at the beginning of the year, or if it will be a smaller rise. But we will certainly have an effect in the coming weeks, and so we are closely monitoring with surveillance [em saúde, ligada à secretaria de saúde do estado] the scenario,” he said.

For virologist Fernando Spilki, coordinator of the BR Corona-omic Network, linked to the Ministry of Science and Technology, analyzes of how the new variant reacts to antibodies should come in the coming weeks. “The sequences are in laboratories for analysis regarding their ability to evade antibodies. These data are going to be important to know how the epidemiological evolution of underlining will be”, he says.

Spilki says it’s still too early to know whether the new strains have a significant immune breakthrough or will have an impact on death tolls. “In a rising context, the variants found perfect terrain here, with a population with a low level of reinforcement and more susceptible to new outbreaks, with the last dose of vaccines received a long time ago. , although it is still difficult to measure how much”, he assesses.

The researchers emphasize the importance of updating with the available booster and appeal to the population to get vaccinated. “It’s a matter of concern because a part of the more susceptible population already had their last booster dose more than four or six months ago, and this could cause concern. It would be important, even if these subvariants are less aggressive, to carry out the update of the vaccination schedule”, says Spilki.

“I am in favor of a booster dose now, even if it is not with the updated vaccines that contain the sublines, for this new stimulated immunity that the vaccine offers to protect against serious cases”, says Naveca.

For the time being, it is still not possible to know whether BE.9 will reach the other regions of the country and how it will behave with BQ.1, its competitor, but the low reinforcement coverage is worrying. “It’s a different scenario, post-vaccine, we have that in our favor [em relação à P.1 ou gama, associada ao colapso da saúde no Amazonas]we do not expect a significant increase in serious cases, but obviously if there is an increase in cases, we have to issue alerts”, he completes.