Covid-19: BA.2 strain is “clearly dominant” in Portugal
The BA.2 lineage of the Ómicron variant of covid-19, considered more transmissible, is “clearly dominant” in Portugal and already represents 76.2% of infections, announced this Tuesday by the National Institute of Health Doutor Ricardo Jorge (INSA) .
“It is estimated that the BA.2 lineage is already clearly dominant in Portugal, representing 76.2% of the positive samples on March 7”, says the INSA report on the genetic diversity of the coronavirus that causes the disease covid-19. .
According to INSA, this strain was detected for the first time in Portugal in random samples by sequencing in the week between December 27, 2021 and January 2, and since then, its “frequency has gradually increased”.
A variant identified by the Health Organization (WHO) as a Health Organization (WHO) identification, several lineages identified by the prefix “BA.1 and BA.2 ancestral lineage”, which is the prefix “BA.1 and the BA. 2 ancestral lineage” (B.1.1. 529) and present an “excess” of proteins, many of them shared.
According to the sequencing data, the BA.1 strain reached a maximum prevalence of 95.6% in the week of January 10-16second time a downward trend began, with the INSA estimating that on Friday responsible for 23.8% of infections.
Recently, the WHO stated that “preliminary studies suggest that the BA.2 appears to be more transmissible than BA.1“, organization highlights that the world data on clinical severity in South Africa, UK, where the difference is not real and the difference in severity, indicate that “BA.2 and BA.1”.
“Reinfection with BA.2 after infection with BA.1 has been documented, but infection with BA.1 provides strong protection against reinfection with BA.2,” the WHO said.
As part of the continuous monitoring of the genetic diversity of SARS-CoV-2 that INSA is developing, they have been a average of 523 sequences per week since the beginning of June 2021, from samples selected at random in laboratories spread over the 18 districts of mainland Portugal and the autonomous regions of the Azores and Madeira, covering an average of 139 municipalities per week.