Adriana santagati
03/10/2021 6:01 AM
Clarín.com
Society
Updated 03/10/2021 8:15 AM
Around the world, VOCs are a central issue at this point in the pandemic.
What are VOCs?
The "variants of concern", an expression in English for "variants of concern": the logical changes that Covid-19 is undergoing, like all viruses in its evolution, but which in some cases may have a potential that implies paying more attention to them.
Scientists everywhere are monitoring SARS-CoV-2 for these VOCs, and a recent study in Brazil hit an unusual finding so far:
patients who were infected with two different variants at the same time
.
It is worth going back to review some concepts that were talked about a lot in this 2021, from the discovery of the British variant, much more contagious than the "standard".
As infections occur,
viruses replicate
.
In this process, there are "errors", changes in the genetic code, which are called
mutations
.
They happen all the time, with all viruses.
In some cases, those mutations can even lead to the virus disappearing.
In others, the virus becomes "more efficient" for its function: that is, it can be more contagious or more resistant to vaccines or treatments.
Apparently, the new variants that appeared in recent months would fall into this last group,
the one of the most efficient
.
The one from South Africa could reduce the effectiveness of certain vaccines and the one from Manaus would be more contagious, as would the British one.
Now, an investigation by Brazilian scientists to be published in the April issue of the journal Virus Research, recorded two cases of patients in whom there was
a co-infection with two different variants
.
The
paper
signed by a team from the National Laboratory for Scientific Computing and the Feevale University of Rio Grande do Sul, confirms in that country the simultaneous infection of two patients with two different lineages.
“After the discovery of a new variant in Rio de Janeiro, we made an effort to trace whether this new lineage that carries the E484K mutation could be found in the second wave of Covid-19 that affects southern Brazil, and we investigated the presence of other possible lineages circulating in the state.
The discoveries include a
new variant originated in Rio Grande do Sul and the simultaneous infection of patients with two different lineages
”, they explain in the study.
The cases occurred in two women, one 32 and the other 33 years old, who recovered without major complications or the need for hospitalization.
But in addition to warning about the possibility of co-infections with two different variants, the investigation warns about
the expansion in the Brazilian territory of the Rio de Janeiro variant
- which indicates that the control measures are not being sufficient - and also about
the emergence of a new variant
, identified as VUI-NP13L, in the state of Rio Grande do Sul.
"These coinfections are a reflection of the
high simultaneous circulation of different virus lineages
in a given geographic space," explained Fernando Spilki, a virologist at Feevale University and one of the study authors, to the scientific news site SciDev.Net.
Spilki warned about the possibility that the conditions for genetic recombination were generated, giving rise to another new lineage that could have several evolutionary advantages at the same time.
However, for the Argentine expert Javier Farina, this discovery
does not directly imply greater potential risks
.
The infectologist, a member of the Argentine Society of Infectology (SADI), clarified that a person infected with the two lineages cannot infect a third person who combines both.
"The new variants are generated by replication of the virus in a person," he remarked.
For Farina, this finding
does not have an impact on severity either
, since the picture should not be more severe than with the two variants separately, as well as contagiousness.
Now, is this expected to happen?
According to the expert, co-infections are not something "hyper frequent" but
they are possible
and have always been identified, for example with two viruses or a virus and a bacterium (such as SARS-CoV-2 and pneumococcus).
In this case, they are two different variants of the Covid.
Pablo Bonheví, former president of SADI, contributed another aspect: for him, they should be "two very different variants one from the other, because they would be behaving like two different viruses to infect a person at the same moment."
Bonheví pointed out that it should be ruled out that the infection has been successive and not simultaneous, and in this sense he explained that it
is possible that the same person is infected first with one lineage and then with another
.
In these cases, he explained, it occurs because although the viruses are not completely different, there is a possibility that the defenses generated by the first variant
do not offer total protection against the second
.
And there may also be cases of cross-infection by other variants that are not detected precisely because the infection given by the first variant is sufficient to protect the infected person from “making clinical expression of the second infection”.
ACE
Look also
They find a new version of the virus that combines two variants
Can vaccinated people transmit the coronavirus?