May 25, 2024

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Delta AY.4.2 spread in 42 countries and the infectiousness 10%-15% higher

DeDelta AY.4.2 spread in 42 countries and the infectiousness 10%-15% higher than Delta variant


Delta+: AY.4.2 spread in 42 countries and the infectiousness 10%-15% higher than Delta variant. “Delta+” has spread at least in 42 countries around the world, the infectiousness is 10%-15% higher than Delta


In recent months, cases of infection with the sub-variant AY.4.2 of the delta strain of the COVID-19 mutant virus have appeared in many countries.

How powerful is this strain called “Delta+” by the media? Will it trigger a new round of pandemic?



Delta mutant strain has spread to 42 countries

According to Worldometer’s real-time statistics, as of 19:00 on November 21,  the cumulative number of confirmed cases of COVID-19 pneumonia worldwide has exceeded 257 million, and the cumulative deaths have exceeded 5.16 million.

On November 19, the global number of new cases in a single day once again approached 600,000.


The WHO recently warned that Europe is facing a “destructive winter.” According to the British Sky News, on November 15 local time, British Health Secretary Javid told members of Parliament that Europe had returned to the “epicenter” of the pandemic.


On October 26, the World Health Organization’s weekly report on the prevalence of the COVID-19 epidemic specifically mentioned the AY.4.2 subfamily.

The report said that since July this year, the number of AY.4.2 sub-line sequencing data submitted globally has been increasing.

As of October 25, more than 26,000 AY.4.2 virus strain sequences in 42 countries around the world have been uploaded to the Global Influenza Data Initiative Database (GISAID).

The report also pointed out that 93% of the AY.4.2 virus strain sequence reports came from the United Kingdom.


The SARS-CoV-2 variants of concern and variants under investigation in England published by the British Health and Safety Agency at the end of October pointed out that although the sequencing data of the virus strain is incomplete, only 10 In December, the proportion of AY.4.2 sub-series in Delta confirmed cases rose from 8.5% at the beginning of October to 11.3% at the end of the month. In the United Kingdom, the delta variant is the main spread of the new coronavirus variant, and the increase in the proportion of the AY.4.2 subline indicates the possibility of this subline developing into a mainstream virus.


In addition to the United Kingdom, such cases were also detected in the United States and Denmark as early as July. Subsequently, the variant virus was also found in Canada, Australia, Japan, and some countries in Western Europe.


The Centre for Health Protection of the Department of Health of the Hong Kong Special Administrative Region Government announced on November 5 that the first case of the “Delta” mutant virus strain AY.4.2 sublineage was found in Hong Kong. The new case is a 46-year-old woman who arrived in Hong Kong from the UK and is an imported case from abroad.



AY.4.2 subvariant is 10%-15% more infectious than Delta


The AY.4.2 subvariant strain, officially known as VUI-21OCT-01, is the “descendant” of the Delta strain. So far, on a global scale, researchers have recorded more than 40 subvariants of Delta, and AY.4.2 is just one of them. Compared with the original Delta strain, there are two typical mutations in the spike protein carried by AY.4.2 when it infects human cells, namely Y145H and A222V.


The report also stated that the “growth speed” of the AY.4.2 subvariant strain and the Alpha strain and the original Delta strain is not the same. Geoffrey Barrett, head of the COVID-19 Genome Project at the Sanger Institute of the Wellcome Foundation in the United Kingdom, and others pointed out that the infectivity of AY.4.2 is 10% to 15% higher than that of the original Delta strain.


According to data from the Sanger Institute, AY.4.2 infection cases have been steadily increasing in England. However, the researchers said that it is not clear whether this sub-variant strain spread in the UK because of the mutation that gave it a biological advantage over other mutant strains, or other reasons that caused it to be in a population with a high infection rate. spread.


The British Health and Safety Agency also pointed out that so far, there is no indication that this subvariant strain will cause more severe cases or reduce the effectiveness of the COVID-19 vaccine.




(source:internet, reference only)

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Important Note: The information provided is for informational purposes only and should not be considered as medical advice.