Today we know about Omicron’s new XBB sub variant

The Corona virus It continues to evolve and spread throughout the world. There is major variation in the virus Omicron, but new subspecies are emerging that are being investigated by the scientific community to study their health implications. One of them is XBBIt is popularly known “Dream Variation” It has now been studied by university researchers Hong Kong.

XBB has already been detected in 35 countries, including Argentina. Hong Kong experts published their study on this mutation in a special issue Lancet Microbiology. It has gained attention since August when the data was uploaded to a global database along with the genome sequence of the virus.

In some Asian countries, such as Singapore, XBB circulation has been associated with increased COVID hospitalizations. However, there is no evidence that this sublineage causes more severe cases in affected populations compared to other types. It is also emphasized that booster doses available in each community still have benefits in preventing severe COVID-19 and death.

Indonesia’s Ministry of Health, headed by Budi Gunadi Sadikin, said on Tuesday, December 6, that XBB and BQ.1 sub-variants have become the main causes of additional Covid-19 cases in Indonesia from October 10 to the end of November. 2022, reached 90% of cases. In Indonesia, the number of people infected with the XBB and BQ.1 sublines has started to decline after peaking a fortnight ago.

The Hong Kong scientists reported in their study that XBB is a rearrangement between the BA.2.10.1 and BA.2.75 subtypes and is classified as a variant under observation. WHO.

Before conducting the study, the researchers noted that there was preliminary evidence that XBB may be associated with an increased risk of relapse. A previous study using a pseudovirus neutralization test and sera from individuals who had received Chinovac’s coronavac vaccine found that XPB is a highly immunogenic subline (ie, can evade the immune system’s defenses).

In the work, they reported that they evaluated the neutralization ability of XBB.1 and XBB.3 compared to BA.5.2 (the strain in widespread circulation since July 2022) and the ancestral strain of the coronavirus using a virus neutralization test.

They found that XBB.1 differs from XBB.3 due to an additional spike mutation, which they named Gly252Val. Serum samples from 30 individuals with or without prior coronavirus infection who had received between two and four doses of a messenger RNA vaccine developed by Pfizer-BioNtech and the CoronaVac vaccine were included.

“Our data showed that both XBB.1 and XBB.3 are more resistant than the ancestral strain and BA.5.2. This pattern of immunosuppression is observed in patients with different histories of vaccination or infection,” they wrote in their published work.

Additionally, they added: “Patients infected with PA.5.2 may not acquire neutralizing antibodies against the XPB sublinage, while patients infected with PA.5 or those with bivalent vaccinees may be at risk of re-infection or infection with the vaccine. of the XBB sub-sequence” than the previous sub-sequences.

The served Funded by the Health and Medical Research Fund, Office of Food and Hygiene, Government of the Special Administrative Region, Advisory Service for Improving Laboratory Surveillance of Emerging Infectious Diseases, and Antimicrobial Research Capacity of the Hong Kong Department of Health. , among other companies.

Consulted by infobae A virology researcher at the National Institute of Agricultural Technology (INTA), Dr. Humberto Debaut pointed out the implications and limitations of the study carried out by Hong Kong scientists: “XBB subtypes have a higher rate of escape compared to other subtypes. Omicron and the ancestral strain of the coronavirus. It is a recombination derived from BA.2.10.1 and BA.2.75. BA.4 And this means that people with covid with BA.5 sublines (most recently circulating) may be re-infected. This may indicate that people with bivalent doses (including BA.4 and BA.5 sublines) are not highly protected against XBB, but more studies are needed to prove this. required

Dr. Debaut also commented: “This study is published Lancet Microbiology It is a neutralization assay by which humoral immunity is measured. In other words, the cellular response that is part of the defense of the immune system is not measured. Therefore, the results can be considered in part because a major part of the immune system is put aside in the face of the possibility of responding to infection with the XBB sublineage. It should also be taken into account that the number of samples of individuals analyzed is small.

“Beyond the Omicron sublines that circulate in every society, it is important to remember today,” the Argentinian scientist said. Reinforcement They are available because they continue to help reduce the risk of serious conditions and death.

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