Fiocruz warns of possible increase in new strain of coronavirus

Researchers from the Oswaldo Cruz Foundation (Fiocruz) warned today (13) of a possible change in the domain of the Ômicron subvariants of SARS-CoV-2 circulating in the country. According to the Fiocruz Genomic Network, the change could mean the growth of the XBB lineage, which has caused a wave of infections in the United States. The BA.5 strain of the Ômicron variant has been dominant in Brazil since mid-2022, after having outperformed other Ômicron subvariants. Fiocruz explains that a specific mutation in a gene of the subvariants of this lineage can be identified by means of RT-PCR test techniques, without the need for complete sequencing. The researchers warn because, in the last week, this genetic characteristic has become less common in the analyzes carried out, which indicates that more viruses present in the samples collected in December may not belong to the BA.5 lineage. “Considering the global scenario of the diversity of Sars-CoV-2 variants, the researchers concluded that the increase in variants without this mutation may correspond to the XBB lineage”, says Fiocruz. The presence of those samples that can carry the XBB lineage increased from less than 5% in early December to 15% in the last week. “The states in which the possible circulation of XBB lineages were detected are Rio de Janeiro, São Paulo, Minas Gerais, Espírito Santo, Bahia, Mato Grosso and Santa Catarina”, adds the foundation. Confirmation of XBB’s circulation in the country will depend on genetic sequencing, which takes place at a slower pace than the technique used. According to Fiocruz, only two samples with the XBB.1.5 subvariant have been sequenced in the country so far, in São Paulo. The XBB.1.5 subvariant was nicknamed in the United States “Kraken”, a monster from Greek mythology, because of the sum of mutations it accumulates. The World Health Organization said that the variant is the most transmissible ever detected since the beginning of the pandemic and asked that countries should evaluate the return of the recommendation for the use of masks for passengers on long-haul flights. The subvariant was responsible for more than a quarter of cases of covid-19 in the United States in the first week of January and has also been detected in countries in Europe.

Agência Brasil