Pattni, Karan 
ORCID: 0000-0002-1122-6246, Hungerford, Daniel ORCID: 0000-0002-9770-0163, Adams, Sarah, Buchan, Iain ORCID: 0000-0003-3392-1650, Cheyne, Christopher P, García-Fiñana, Marta ORCID: 0000-0003-4939-0575, Hall, Ian, Hughes, David M, Overton, Christopher E ORCID: 0000-0002-8433-4010, Zhang, Xingna ORCID: 0000-0002-8849-2112 et al (show 1 more authors)
(2022)
Effectiveness of the BNT162b2 (Pfizer-BioNTech) and the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccines for reducing susceptibility to infection with the Delta variant (B.1.617.2) of SARS-CoV-2
BMC Infectious Diseases, 22 (1).
270-.
ISSN 1471-2334, 1471-2334
Abstract
Abstract Background From January to May 2021 the alpha variant (B.1.1.7) of SARS-CoV-2 was the most commonly detected variant in the UK. Following this, the Delta variant (B.1.617.2) then became the predominant variant. The UK COVID-19 vaccination programme started on 8th December 2020. Prior to the Delta variant, most vaccine effectiveness studies focused on the alpha variant. We therefore aimed to estimate the effectiveness of the BNT162b2 (Pfizer-BioNTech) and the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vaccines in preventing symptomatic and asymptomatic infection with respect to the Delta variant in a UK setting. Methods We used anonymised public health record data linked to infection data (PCR) using the Combined Intelligence for Population Health Action resource. We then constructed an SIR epidemic model to explain SARS-CoV-2 infection data across the Cheshire and Merseyside region of the UK. Vaccines were assumed to be effective after 21 days for 1 dose and 14 days for 2 doses. Results We determined that the effectiveness of the Oxford-AstraZeneca vaccine in reducing susceptibility to infection is 39% (95% credible interval [34, 43]) and 64% (95% credible interval [61, 67]) for a single dose and a double dose respectively. For the Pfizer-BioNTech vaccine, the effectiveness is 20% (95% credible interval [10, 28]) and 84% (95% credible interval [82, 86]) for a single-dose and a double dose respectively. Conclusion Vaccine effectiveness for reducing susceptibility to SARS-CoV-2 infection shows noticeable improvement after receiving two doses of either vaccine. Findings also suggest that a full course of the Pfizer-BioNTech provides the optimal protection against infection with the Delta variant. This reinforces the need to complete the full course programme to maximise individual protection and reduce transmission.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | SARS-CoV-2, COVID-19, Vaccine, SIR, Modelling, Infectious disease, Effectiveness |
| Divisions: | Faculty of Health & Life Sciences Faculty of Health & Life Sciences > Inst. Infection, Vet & Ecological Sciences Faculty of Science & Engineering > School of Physical Sciences |
| Depositing User: | Symplectic Admin |
| Date Deposited: | 21 Mar 2022 09:10 |
| Last Modified: | 22 Jan 2026 08:57 |
| DOI: | 10.1186/s12879-022-07239-z |
| Open Access URL: | https://doi.org/10.1186/s12879-022-07239-z |
| Related Websites: | |
| URI: | https://livrepository.liverpool.ac.uk/id/eprint/3151212 |
| Disclaimer: | The University of Liverpool is not responsible for content contained on other websites from links within repository metadata. Please contact us if you notice anything that appears incorrect or inappropriate. |
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