Compared to the Delta variant, which was first found in India, the alpha variant (first found in the United Kingdom) caused only a fall of 2.3 times in the power of antibodies extracted from recovered patients from Covid-19
There was a six-time drop in the capacity of the antibodies of a past infection to neutralize the Delta variant of SARS-COV-2, and a greater reduction of eight times in the power of vaccines antibodies, according to a pair. Revised study led by researchers from India and the United Kingdom.
The study, they say that the authors combine the findings of laboratory experiments and the analysis of progress cases to join signs of the Delta variant, or B.1,617.2, be better in replication and resist antibodies, these Features helped him to quickly overcome the alpha. (B.1.1.7) Variant that was at that time the most transmissible version of the coronavirus.
“We have shown that the delta variant is better to replicate and spread that other variants of common use. There is also evidence that neutralizing antibodies produced as a result of an infection or pre-vaccination are less effective to stop this variant. It is likely that these factors They have contributed to the devastating wave in India during the first quarter of 2021, where there is half of the cases were individuals who had previously been infected with a previous variant, “said Professor Ravi Gupta of the Cambridge Institute of Therapeutic Immunology and Disease Infectious, which is one of the authors.
Compared to the Delta variant, which was first found in India, the alpha variant (first found in the United Kingdom) caused only a fall of 2.3 times in the power of antibodies extracted from recovered patients from Covid-19 . The study involved antibodies extracted from people who had past infection, or received the Oxford-AstraZeneca vaccine or the Pfizer-Biontech shot. These were made to neutralize alpha, beta and delta variants in a laboratory.
This part of the analysis showed that the most evasive variant was beta (first found in South Africa), followed by Delta and Alpha.
The second part of the study involved the analysis of advance infections between 112 health workers in three Hospitalsin Delhi, which showed that the majority were cases of Delta variant (99 infections), which confirms that the mutated virus was more likely that It caused diseases in people vaccinated compared to other people. Versions of SARS-COV-2. The study found a similar fall in the power of the therapy with laboratory cultured antibodies, such as Bamlanivimab and Imdevimab.
“Infection in health workers vaccinated with the Delta variant is a major problem. Although they can only experience slight Covid-19, they risk people who have sub-optimal immune responses to vaccination due to the conditions of Underlying health, and these patients may be at risk of serious illness, “said Dr. Anurag Agarwal, Director, Institute of Genomics and Integrating Biology, which is also part of the study.
The authors suggest due to this risk, the infections control measures, such as masking, social distancing and hand washing, should continue even in the “era after vaccination”.
The study also addresses why the Delta variant seems to be more in a way than others, despite showing less resistance to antibodies than the beta variant. Appointment The laboratory analysis showing the delta variant to be more efficient to enter human cells and replicate inside.
It achieves this, in particular, mutating so that its fusion with the host cell is more efficient. Once inside a cell, they can also be more widely replicated compared to the alpha variant, according to the experiments performed in epithelial cells (the coating) of the airway and the lungs, as well as organoids 3D (mini cultivated organs of The cells of the airway).
These clues explain what has been observed throughout the world, starting with India in mid-April. The variant was quickly swept through the country, the overwhelming tests, as well as the treatment capabilities. The variant then pushed the trajectories of cases in countries.