MOSCOW, January 10. /TASS/. The XBB.1.5 subvariant of the Omicron coronavirus strain, nicknamed Kraken, is more contagious because of changes in the structure of S-protein, Head of the Yekaterinburg Research Institute of Viral Infections at the Russian sanitary watchdog’s Vector Research Center of Virology and Biotechnology Alexander Semyonov told TASS on Tuesday.

"Kraken is another variant of the coronavirus, it is the same coronavirus but it has a slightly changed structure of spike protein, which increased its contagiousness a little bit and apparently made it possible for the virus to escape immune defense in those who have immunity to the previous variants," the expert pointed out.

According to Semyonov, researchers are already familiar with the genetic structure of the virus variant that "is spreading fast." The XBB.1.5 subvariant has not been recorded in Russia yet, he added.

"Like other coronavirus mutations, Kraken marks the pathogen’s attempt to remain in the population and, so to say, reproduce successfully. Apparently, it doesn’t cause more severe forms of the disease, at least no such data is available at this point," Semyonov emphasized.

However, the XBB.1.5 subvariant, which is being closely monitored by researchers, emerged during the season of the flu and acute respiratory infections. This is why experts around the world agree on the need to take precautions. "First of all, the recommendations are to wear masks in public places, avoid unprotected contact, refrain from visiting places of mass gatherings unless necessary, stay at home and call a doctor at the first signs of infection," Semyonov concluded.