Two new sub-variants of omicron have been identified in Brazil

Two new strains of the omicron variant of the coronavirus were first identified in Brazil. The two breeds, already known to the rest of the world, were found in samples from the capital and interior of the state of São Paulo.

The two virus isoforms were identified using the Sars-CoV-2 Variant Alert Network, coordinated by the Instituto Butantan in São Paulo, and linked to the State Secretariat for Science, Research and Development in Health. The first variant, known as XBB.1, originates from the recombination of two other sublines, BA.2.10.1 and BA.2.75, and is considered a ‘cousin’ to BQ.1, which was recently identified in Brazil.

Because it comes from two Omicron strains that had a high frequency in some European countries, the World Health Organization (WHO) classifies the strain as a variant under surveillance (VUM). It was found from a sample of the virus from São Paulo. To date, 2,025 samples of this sub-variant have already been registered on the Gisaid platform, which acts as a bank of genetic sequences for the virus.

Another identified variant is CK.2.1.1, based on a sample from the city of Ribeirao Preto (about 300 km from the capital). According to the Butantan Institute, samples containing the sub-variants were collected between the weeks of October 16 and November 5 by the laboratories that make up the monitoring network. CK.2.1.1 has already been identified in 342 samples from Germany, Denmark, Spain, the United States and Austria, but this is the first time it has been detected in Brazil.

Last Saturday (12), Fiocruz Amazônia announced the identification of its new Amazonas variant, BE.9. It originated from the omicron subline BA.5.3.2 and was responsible for the recent increase in cases in the state from September to October. BE.9 is a “sister” strain to BQ.1. Another minor variant, BQ.1.1, has been identified in the country, particularly in the state of SP.

Generally, these sub-variants contain mutations in the cell receptor-binding region and in the spike protein (the molecular hook that the coronavirus uses to enter the host), which may be related to further immune escape.

A patient infected with BQ.1 died in São Paulo on Monday (7). She had comorbidities and was bedridden, according to a note from the state health department. So far, more testing is needed to see what kind of escape these vaccine sub-variants, including the bivalent forms, have, and whether they are more aggressive. (Anna Potalo/Folhabers)