Delta is 8 times less sensitive to vaccine antibodies than the original Wuhan strain

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The Delta variant is eight times less sensitive to the antibodies generated by vaccination with the Pfizer and AstraZeneca vaccines than the original Wuhan strain, according to UK research. The study also found that the Delta variant was more efficient at replicating than the Alpha variant and was able to replicate and enter cells better than the Kappa variant thanks largely to changes in the spike protein of Delta. The authors say this may explain the dominance of Delta. The research also found the AstraZeneca vaccine was found to be less effective against the Delta variant than other variants prompting the authors to conclude that we need strategies to boost vaccine responses against variants. They say we will also need to pay attention to infection control procedures in the post-vaccine era.

Journal/conference: Nature

Link to research (DOI): 10.1038/s41586-021-03944-y

Organisation/s: University of Cambridge, UK

Funder: This study was supported by the Cambridge NIHRB Biomedical Research Centre. We would also like to thank Ankur Mutreja. We would like to thank Thushan de Silva for the Delta isolate and Kimia Kimelian. SAK is supported by the Bill and Melinda Gates Foundation via PANGEA grant: OPP1175094. I.A.T.M.F. is funded by a SANTHE award (DEL-15-006). We would like to thank Paul Lehner for Calu-3 cells. We would like to thank Clare Lloyd and Sejal Saglani for providing the primary airway epithelial cultures, and James Voss for HeLa ACE2. We thank the Geno2pheno UK consortium. The authors acknowledge support from the G2P-UK National Virology consortium funded by MRC/UKRI (grant ref: MR/W005611/1).This study was also supported by The Rosetrees Trust and the Geno2pheno UK consortium. SF acknowledges the EPSRC (EP/V002910/1). KS is supported by AMED Research Program on Emerging and Re-emerging Infectious Diseases (20fk0108270 and 20fk0108413), JST SICORP (JPMJSC20U1 and JPMJSC21U5) and JST CREST (JPMJCR20H4).

Media release

From: Springer Nature

Virology: Characterising the SARS-CoV-2 Delta variant

Related documents (1)

The recent, rapid dominance of the SARS-CoV-2 B.1.617.2 (Delta) variant over pre-existing lineages may be due to its increased infectivity and reduced sensitivity to neutralizing antibodies, according to a study published in Nature. The research suggests that continued infection control measures may still be required in the post-vaccination era.

First identified in the Indian state of Maharashtra in late 2020, the SARS-CoV-2 Delta variant has since spread throughout India and to over 90 countries worldwide, rapidly outcompeting pre-existing genetic variants such as B.1.1.7 (Alpha) and B.1.617.1 (Kappa).

Ravindra Gupta and colleagues studied the differential properties of genetic variants of SARS-CoV-2. Compared to the Wuhan-1 variant of the virus bearing the D614G mutation (against which current vaccines have been developed), Delta was found, in laboratory experiments, to be six-fold less sensitive to antibodies from individuals who had recovered from a previous infection. It was also eight-fold less sensitive to antibodies produced in response to two doses of either the Pfizer–BioNTech or AstraZeneca vaccines. In laboratory models of the human airway, the Delta variant was more efficient at replicating than the Alpha variant — an advantage that is associated with the predominantly cleaved configuration of the spike protein of Delta. This spike protein also permitted the Delta variant to replicate and enter cells at a higher rate than that of the Kappa variant, which the authors conclude may explain the dominance of Delta.

Over a six-week period (March to April 2021) the team analysed SARS-CoV-2 infections in over 130 healthcare workers at three hospitals in Delhi who had received two doses of the AstraZeneca vaccine. In these individuals, the AstraZeneca vaccine was found to be less effective against the Delta variant relative to non-Delta variants.

The authors conclude that their findings highlight the need to develop strategies to enhance vaccine responses against variants of SARS-CoV-2.

Virology: Characterising the SARS-CoV-2 Delta variant

Related documents (1)

The recent, rapid dominance of the SARS-CoV-2 B.1.617.2 (Delta) variant over pre-existing lineages may be due to its increased infectivity and reduced sensitivity to neutralizing antibodies, according to a study published in Nature. The research suggests that continued infection control measures may still be required in the post-vaccination era.

First identified in the Indian state of Maharashtra in late 2020, the SARS-CoV-2 Delta variant has since spread throughout India and to over 90 countries worldwide, rapidly outcompeting pre-existing genetic variants such as B.1.1.7 (Alpha) and B.1.617.1 (Kappa).

Ravindra Gupta and colleagues studied the differential properties of genetic variants of SARS-CoV-2. Compared to the Wuhan-1 variant of the virus bearing the D614G mutation (against which current vaccines have been developed), Delta was found, in laboratory experiments, to be six-fold less sensitive to antibodies from individuals who had recovered from a previous infection. It was also eight-fold less sensitive to antibodies produced in response to two doses of either the Pfizer–BioNTech or AstraZeneca vaccines. In laboratory models of the human airway, the Delta variant was more efficient at replicating than the Alpha variant — an advantage that is associated with the predominantly cleaved configuration of the spike protein of Delta. This spike protein also permitted the Delta variant to replicate and enter cells at a higher rate than that of the Kappa variant, which the authors conclude may explain the dominance of Delta.

Over a six-week period (March to April 2021) the team analysed SARS-CoV-2 infections in over 130 healthcare workers at three hospitals in Delhi who had received two doses of the AstraZeneca vaccine. In these individuals, the AstraZeneca vaccine was found to be less effective against the Delta variant relative to non-Delta variants.

The authors conclude that their findings highlight the need to develop strategies to enhance vaccine responses against variants of SARS-CoV-2.

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