Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study

Background: We used nationwide data to examine relative vaccine effectiveness (rVE) of the Comirnaty mRNA vaccine (Pfizer–BioNTech (original), hereafter Comirnaty, against the Omicron variants (BA.1 and BA.2) during 2022 in Aotearoa New Zealand (NZ). Method: We analysed a national cohort of 3.15 mil...

Full description

Saved in:
Bibliographic Details
Main Authors: J. Paynter, P. McIntyre, J. Wiki, N. Nghiem, B. Liu, L. Marek, M. Hobbs
Format: Article
Language:English
Published: Elsevier 2025-06-01
Series:Vaccine: X
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S259013622500018X
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850226206833639424
author J. Paynter
P. McIntyre
J. Wiki
N. Nghiem
B. Liu
L. Marek
M. Hobbs
author_facet J. Paynter
P. McIntyre
J. Wiki
N. Nghiem
B. Liu
L. Marek
M. Hobbs
author_sort J. Paynter
collection DOAJ
description Background: We used nationwide data to examine relative vaccine effectiveness (rVE) of the Comirnaty mRNA vaccine (Pfizer–BioNTech (original), hereafter Comirnaty, against the Omicron variants (BA.1 and BA.2) during 2022 in Aotearoa New Zealand (NZ). Method: We analysed a national cohort of 3.15 million adults (18+ years) who had received at least two doses of Comirnaty by March 2022. Data sources included national administrative records of vaccination, hospitalisation, ICU admission and death. Cox regression was used to estimate hazard ratios in recipients of three vaccine doses compared to recipients of two doses. Results: Amongst adults, three vaccine doses provided significantly greater protection against hospitalisation attributable to Covid-19 than two doses, relative vaccine effectiveness (rVE) was 50 %, 95 % Confidence Interval (CI) 45–55 %) at peak virus circulation. The vaccine was effective for Māori, Pacific Peoples and those aged over 50 years however, the protection given by vaccination waned throughout the study period. The booster was also significantly more effective at preventing ICU admission or death with an rVE (3 vs 2 doses) of 53 %, 95 % CI 49–55 %. It was consistent for Māori, 49 %, 95 %CI 41–56 % and Pacific Peoples 52 %, 95 % CI 41–62 %, and those aged over 50 years, 54 %, 95 % CI 51–57 %. Conclusion: The study provides important insights into relative vaccine effectiveness of the Comirnaty booster doses against Omicron variants in NZ in 2022 in an infection naive population. The findings highlight the importance of booster doses in combatting hospitalisation, ICU admission and death during the 2022 Omicron wave.
format Article
id doaj-art-35a265fda08442bfa0caa21d36166a79
institution OA Journals
issn 2590-1362
language English
publishDate 2025-06-01
publisher Elsevier
record_format Article
series Vaccine: X
spelling doaj-art-35a265fda08442bfa0caa21d36166a792025-08-20T02:05:08ZengElsevierVaccine: X2590-13622025-06-012410062410.1016/j.jvacx.2025.100624Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort studyJ. Paynter0P. McIntyre1J. Wiki2N. Nghiem3B. Liu4L. Marek5M. Hobbs6School of Population Health, General Practice and Primary Healthcare, University of Auckland, New Zealand; Corresponding author.Women's & Children's Health, Dunedin School of Medicine He Rau Kawakawa, University of Otago, Te Whare Wānanga o Ōtākou, Dunedin, Ōtepoti, New ZealandGeoHealth Laboratory Te Taiwhenua o te Hauora, University of Canterbury Te Whare Wānanga o Waitaha, Christchurch, Otautahi, New ZealandDepartment of Public Health, University of Otago, Wellington, New Zealand; John Curtin School of Medical Research, Australian National University, Canberra, AustraliaNational Centre for Immunisation Research and Surveillance, Sydney, AustraliaGeoHealth Laboratory Te Taiwhenua o te Hauora, University of Canterbury Te Whare Wānanga o Waitaha, Christchurch, Otautahi, New ZealandGeoHealth Laboratory Te Taiwhenua o te Hauora, University of Canterbury Te Whare Wānanga o Waitaha, Christchurch, Otautahi, New Zealand; Faculty of Health Te Kaupeka Oranga, University of Canterbury Te Whare Wānanga o Waitaha, Christchurch, Otautahi, New Zealand; College of Health, Wellbeing & Life Sciences, Sheffield Hallam University, Sheffield, Yorkshire, United KingdomBackground: We used nationwide data to examine relative vaccine effectiveness (rVE) of the Comirnaty mRNA vaccine (Pfizer–BioNTech (original), hereafter Comirnaty, against the Omicron variants (BA.1 and BA.2) during 2022 in Aotearoa New Zealand (NZ). Method: We analysed a national cohort of 3.15 million adults (18+ years) who had received at least two doses of Comirnaty by March 2022. Data sources included national administrative records of vaccination, hospitalisation, ICU admission and death. Cox regression was used to estimate hazard ratios in recipients of three vaccine doses compared to recipients of two doses. Results: Amongst adults, three vaccine doses provided significantly greater protection against hospitalisation attributable to Covid-19 than two doses, relative vaccine effectiveness (rVE) was 50 %, 95 % Confidence Interval (CI) 45–55 %) at peak virus circulation. The vaccine was effective for Māori, Pacific Peoples and those aged over 50 years however, the protection given by vaccination waned throughout the study period. The booster was also significantly more effective at preventing ICU admission or death with an rVE (3 vs 2 doses) of 53 %, 95 % CI 49–55 %. It was consistent for Māori, 49 %, 95 %CI 41–56 % and Pacific Peoples 52 %, 95 % CI 41–62 %, and those aged over 50 years, 54 %, 95 % CI 51–57 %. Conclusion: The study provides important insights into relative vaccine effectiveness of the Comirnaty booster doses against Omicron variants in NZ in 2022 in an infection naive population. The findings highlight the importance of booster doses in combatting hospitalisation, ICU admission and death during the 2022 Omicron wave.http://www.sciencedirect.com/science/article/pii/S259013622500018XCominarty vaccineRelative vaccine effectivenessOmicronNew ZealandCohort
spellingShingle J. Paynter
P. McIntyre
J. Wiki
N. Nghiem
B. Liu
L. Marek
M. Hobbs
Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study
Vaccine: X
Cominarty vaccine
Relative vaccine effectiveness
Omicron
New Zealand
Cohort
title Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study
title_full Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study
title_fullStr Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study
title_full_unstemmed Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study
title_short Using nationwide data to examine the relative effectiveness of Covid-19 vaccination against omicron amongst a population with low prior rates of SARS-CoV-2 infection: A cohort study
title_sort using nationwide data to examine the relative effectiveness of covid 19 vaccination against omicron amongst a population with low prior rates of sars cov 2 infection a cohort study
topic Cominarty vaccine
Relative vaccine effectiveness
Omicron
New Zealand
Cohort
url http://www.sciencedirect.com/science/article/pii/S259013622500018X
work_keys_str_mv AT jpaynter usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy
AT pmcintyre usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy
AT jwiki usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy
AT nnghiem usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy
AT bliu usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy
AT lmarek usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy
AT mhobbs usingnationwidedatatoexaminetherelativeeffectivenessofcovid19vaccinationagainstomicronamongstapopulationwithlowpriorratesofsarscov2infectionacohortstudy