Lancet study shows Omicron XBB.1.5 variant is highly contagious and infectious

“Our data suggest that XBB.1.5 will rapidly spread around the world in the near future,” said Jumpei Ito of the university’s Division of Systems Virology.

Earlier in January, the Omicron XBB.1.5 strain was the fastest-spreading strain worldwide. This tension was dominant in countries like America, Britain. India also saw the XBB.1.5 strain of COVID in the country. The XBB.1.5 strain is a relative of the Omicron XBB variant, which is a recombinant of the Omicron BA.2.10.1 and BA.2.75 subvariants.

In January, the World Health Organization (WHO) revised the risk assessment for Omicron XBB.1.5 version “Low” to “Moderate”. The WHO noted that the variant was likely to contribute to the increase in case incidence globally and also noted that ‘the number of cases associated with XBB.1.5 was small and thus the severity yet to be assessed with confidence’ Can’t be done.’

Speaking of symptoms, the COVID infections led by XBB.1.5 were having the same effect on people as the previous variants. Classic COVID symptoms like runny nose, sore throat, headache are observed in patients who report positive for COVID. Experts had said that XBB.1.5 was more likely to report flu-like symptoms, such as feeling very sick in general due to a high fever.

Read also: Troubled by fever and cough? How do you know its H3N2 or the new COVID variant XBB 1.16?

Coming back to the study, Professor Kei Sato of the Department of Systems Virology said that XBB.1.5 has the potential to cause the next surge of the pandemic. He further said that the variant needed to be carefully monitored “to protect public health”.

Studying emerging variants of the SARS-CoV-2 omicron lineage, the research team found that the SARS-CoV-2 omicron XBB.1.5 variant has a new mutation in the spike (S) protein – the protein that binds tightly to the virus keeps. human angiotensin converting enzyme-2 (ACE2) receptor, thus facilitating invasion of human cells.

Further experiments using lentivirus-based pseudoviruses also showed that XBB.1.5 had approximately 3-fold higher infectivity than XBB.1. The study led to another important discovery from the point of view of vaccination that the XBB.1.5 S protein was found to be highly resistant to neutralization antibodies derived from successful infection with the BA.2/BA.5 subvariants.

In other words, patients with prior infection with the BA.2/BA.5 subvariant may not show strong immunity against XBB.1.5, increasing their susceptibility to infection and disease, the study showed.

Yusuke Kosugi, Department of Systems Virology, Department of Microbiology and Immunology, said, “The results of our virological experiments explain why the Omicron XBB.1.5 variant has higher transmissibility than the previous variant: this variant retained a binding affinity for human ACE2 while maintaining a Strong binding ability is achieved.High ability to evade neutralizing antibodies.