The delta variant of the corona virus (p.1.617) was the first case documented in India in October 2020 and was classified as a variant (VOC, English) by the World Health Organization in May 2021, and has been found in many more, according to the World Health Organization, so far in 80 countries.
So far, the WHO has identified four VOCs (anxiety variant): alpha (B.1.1.7), beta (B.1.351), gamma (P.1) and delta.
There have been reports of highly contagious sublineage of the delta variant, sometimes referred to as Delta Plus or AY1. This variant contains the K417N mutation, which is commonly found in the beta variant first identified in South Africa.
At this time, there are not many cases of this variation, according to the website PANGO Lineages created by scientists, which allows users to assign the most possible lines to SARS-CoV-2 footage.
“This is a mutation that has been linked again with better ability to avoid vaccines and increased spread,” said Deepti Kurtasani, an epidemiologist at Queen Mary University in London.
Like all genres, the Delta accumulates mutations relatively easily, so it quickly gave way to a kind of “family” that has three versions, B-1617-1, B-1617-2 and B-1.617-3.
Of these, the most widespread is the P-1617-2, which is considered to be 60% more efficient than the alpha variant, thanks to some mutations such as the K4177, gamma variant, beta and E-484Q identified in South Africa, and gamma variants. The B-1617-2 variant has now also changed, with the creation of the new version, denoted by the letters B-1617-2-1 or, more simply, AY-1.
It is important to remember that viruses have many mutations, said Franோois Baloux, director of the Institute of Genetics at University College London.
In the UK, the delta variant has been detected more than 46,000 times (as of June 18), according to GISAID, a scientific initiative that facilitates data sharing. This is the highest number of delta cases ever identified in a country.
Data from PHE, a UK healthcare agency, indicate that more than 90% of new COVID-19 cases in the region are delta variants.
As of June 9, the UK had confirmed more than 42,000 cases of delta variation, with an increase of nearly 30,000 from June 2 to 9, according to PHE data. In PHE-confirmed cases, the majority were unconfirmed or received only one dose of the vaccine.
PHE research has found that the delta variant is associated with a 64% higher chance of spreading at home compared to the first identified alpha variant (p.1.1.7) in the UK.
“What we initially noticed in India is that the Delta variant is growing or growing faster than the Kent or Alpha variant that first appeared in the UK,” Kurdasani said, “as far as we know the alpha variant was already more contagious than the original virus.”
“If the transmission of a variant is 50-60% higher than the previous variant, which is 60% more contagious than the previous virus, we increase the spread of the virus up to three times,” Kurtasani said.
WHA COVID-19 Technical Director Maria van Kerkov said on Twitter that the delta variant is more transmissible than the alpha variant and the original corona virus.
However, little is known about whether the delta variant causes more deaths.
From February 1 to June 7, 42 people died in the UK due to the delta variation. Of these, 23 were not vaccinated, seven died more than 21 days after the first vaccination, and 12 died more than two weeks after the second dose.
The PHE reported that the delta variant was more likely to be admitted to the hospital compared to the alpha variant. From June 7 to 13, more than 1,300 people were hospitalized for all types of COVID-19, an increase of 43% over the previous week.
“UK reports say it is more likely to be admitted to hospital, so it should come as no surprise if it is found to be very dangerous,” Kurtzani said.
Excessive spread of a virus leads to a rapid increase in cases, which means more hospitalization and death in the end, Kurtasani said. The vaccine will help, but many around the world are still waiting for their shots.
There are other factors that can affect a person who dies from the virus, such as comorbidities and socioeconomic determination. “It’s very difficult to measure because there are so many confusing variables,” Balox said. But we need more information to see if this is really a combination of factors.
A pending study by the UK company PHE has found that two doses of COVID-19 vaccine are highly effective in preventing hospitalization.
The Pfizer-Bioentech vaccine was 94% effective against hospital admission after a single dose and 96% effective against hospital admission after two doses. AstraZeneca was 71% effective after one dose and 92% after two.