COVID-19: Sequencing finds higher presence of subvariant BA.2
The sequencing of SARS-CoV-2 samples in Brazil shows an increased presence of BA.2, a subvariant of Omicron. The data were disclosed today (Apr. 8) by the Fiocruz Genomics Network. The samples were sequenced until March 31.
Despite the signs that the subvariant is gaining ground in the country, as was the case in the US and Europe, the scientists believe that more information is needed before the phenomenon is confirmed.
In February, the BA.2 subvariant was identified in 1.1 percent of the genomes sequenced. In March, this increased to 3.4 percent. Cumulative figures show the BA.1 (19,555 genomes) and the BA.1.1 (4,290 genomes) strains still for the majority of Omicron samples, but BA.2 has been reported in 151 genomes.
After it spread and caused a peak in cases earlier this year, Omicron became the dominant variant in Brazil, replacing the Delta variant, which was prevalent throughout the second half of last year. In the study published today, Fiocruz adds it took longer for Omicron to become dominant in North Brazil, but now it completely dominates the COVID-19 epidemiological landscape in the country.
The update released today was based on the sequencing of 1,766 genomes at the Fiocruz Laboratory for Respiratory Viruses and Measles as well as five other Fiocruz centers in the states of Amazonas, Ceará, Pernambuco, Paraná, and Bahia.
Among other reasons, monitoring variants is crucial to identifying new mutations of the virus and ascertaining its transmissibility and resistance to antibodies.
