MOSCOW, Oct 21 Reuters - Russia has reported isolated cases of COVID - 19 with a subvariant of the Delta variant that is believed to be even more contagious, the state consumer watchdog's senior researcher said on Thursday.
The researcher, Kamil Khafizov, said the AY. 4.2 subvariant may be around 10% more infectious than the original Delta - which has driven new cases and deaths to a series of record daily highs in Russia - and could eventually replace it.
However, he said this was likely to be a slow process.
The vaccines are effective enough against this version of the virus, which is not so different as to dramatically change the ability to bind to antibodies, he said.
4.2 subvariant is also on an increasing trajectory in England and had already accounted for about 6% of all sequences generated on the week beginning Sept. 27, a UK Health Security Agency report said on Oct. 15.
On Wednesday, the British Health Minister said there was no reason to believe the subvariant posed a greater threat than Delta.
Russian immunologist Nikolay Kryuchkov said Delta and its subvariants would remain dominant and might in the future adapt to vaccines, especially where vaccination rates are below or just above 50%.
But it seems to me that a revolutionary jump will not happen, because the coronavirus, like any organism, has an evolutionary limit, and the evolutionary jump has already happened, he said.
The Russian health ministry had no immediate comment.
Vladimir Putin announced the strictest lockdown measures since June of last year, a day after Moscow's mayor approved a government proposal for a week-long workplace shutdown at the start of November.