|Pedestrians wearing masks walk on a street in Moscow, Russia. © AFP=News1|
As the AY 4.2 mutation, so-called ‘Delta Plus’, a sub-line of the new coronavirus infection (COVID-19) delta mutation, has spread in major countries, the world is paying attention. This is because of concerns that it is more contagious than the existing delta mutation and may impair vaccine efficacy.
According to the BBC and CNBC on the 21st (local time), AY 4.2 mutations have been reported in Britain, the United States, Israel, and Russia.
The country with the highest prevalence of AY 4.2 mutation is the UK. British health officials said that AY 4.2 mutations accounted for 6% of infections in the country in the week starting from the 27th of last month. The UK, which lifted quarantine restrictions since July, is experiencing a resurgence of COVID-19, with 40,000 to 50,000 confirmed cases a day. Some experts believe that the spread of AY 4.2 is one of the causes.
The Centers for Disease Control and Prevention (CDC) announced in a briefing on the 20th that AY 4.2 was also found in the United States. CDC Director Rochelle Wallensky said at a briefing, “The AY 4.2 mutation has been drawing attention recently.” This sub-mutation also appears occasionally in the United States, but until recently, no increase in this mutation or cluster infection was confirmed.
The Israeli Ministry of Foreign Affairs also issued a statement on the same day and announced that a sub-lineage mutation of the delta mutation had occurred in the country, and that the first confirmed case of the mutation was an 11-year-old boy who arrived from Moldova. However, the boy was confirmed positive during the arrival process at the airport, and no other contacts were found.
Russia has already reported several cases of AY 4.2. The state-run Rianovosti news agency said that AY 4.2 may have already spread widely in Russia, citing the comments of senior researcher Kamil Kaizov of the state-run consumer monitoring agency.
Like the UK, Russia is experiencing an explosion in infections, with the number of new confirmed cases and deaths hitting a record high. President Vladimir Putin has even ordered a nine-day paid holiday from the 30th to the 7th of next month.
Evidence that AY 4.2 is more contagious than the existing delta mutation has not yet been confirmed, but some analyzes suggest that it is more contagious.
Dr. Jeffrey Barrett of the Wellcome Trust Sanger Institute and Professor François Vallus of University College London (UCL) said in an interview with the Financial Times (FT) that AY 4.2 could be 10 to 15 percent more powerful than the conventional delta mutation.
Meanwhile, the delta mutation (B.1.617.2), which was first discovered in India last summer and swept around the world this year, is constantly evolving and producing new mutations.
The sub-line mutant strain (B.1.617.2.1), known as delta plus this spring, is collectively referred to as delta plus along with other sub-lineages (AY1, AY2) of the delta mutation that have emerged since then, but the US Centers for Disease Control and Prevention (CDC) etc. have been collected