Waning protection after vaccination and prior infection against COVID-19-related mortality over 18 months
Dietler, Dominik LU
; Kahn, Fredrik
LU
; Inghammar, Malin
LU
and Björk, Jonas
LU
(2023)
In Clinical Microbiology and Infection
29(12).
p.1573-1580
- Abstract
OBJECTIVES: Evidence on waning patterns in protection from vaccine-induced, infection-induced, and hybrid immunity against death is scarce. The aim of this study is to assess the temporal trends in protection against mortality.
METHODS: Population-based case-control study nested in the total population of Scania Region, Sweden using individual-level registry data of COVID-19-related deaths (<30 days after positive SARS-CoV-2 test) between 27 December 2020 and 3 June 2022. Controls were matched for age, sex, and index date. Conditional logistic regression was used to estimate the preventable fraction (PF) from vaccination (PF
vac corresponding to vaccine effectiveness; ≥2 vaccine doses vs. 0 doses), prior infection (PF ... (More)OBJECTIVES: Evidence on waning patterns in protection from vaccine-induced, infection-induced, and hybrid immunity against death is scarce. The aim of this study is to assess the temporal trends in protection against mortality.
METHODS: Population-based case-control study nested in the total population of Scania Region, Sweden using individual-level registry data of COVID-19-related deaths (<30 days after positive SARS-CoV-2 test) between 27 December 2020 and 3 June 2022. Controls were matched for age, sex, and index date. Conditional logistic regression was used to estimate the preventable fraction (PF) from vaccination (PF
vac corresponding to vaccine effectiveness; ≥2 vaccine doses vs. 0 doses), prior infection (PF
inf), and hybrid immunity (PF
hybrid). PF was calculated as one minus odds ratio. Models were adjusted for comorbidities, long-term care facility residence, prior infection (for PF
vac), country of birth, socio-economic conditions, and time since last vaccination (for PF
inf).
RESULTS: In total, 14 936 individuals (1440 COVID-19-related deaths and 13 496 controls) were included in the case-control analyses (45% females, median age: 84 years). PF
vac was above 90% during the first month after vaccination, regardless of the number of vaccine doses. After 6 months, PF
vac of two doses waned to 34% (95% CI: -30% to 66%). PF
inf for people surviving a SARS-CoV-2 infection waned from 88% (-16% to 99%) 3 months after infection to 62% (34-79%) after 9 months. No differences in waning patterns in PF
vac were seen between virus variants, gender, and age.
DISCUSSION: Given the waning of protection against death, continuous surveillance of population immunity status, particularly among the most vulnerable population groups, could help to further fine-tune vaccination recommendations.
(Less)
- author
- Dietler, Dominik
LU
; Kahn, Fredrik
LU
; Inghammar, Malin
LU
and Björk, Jonas
LU
- organization
- publishing date
- 2023-08-12
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Clinical Microbiology and Infection
- volume
- 29
- issue
- 12
- pages
- 1573 - 1580
- publisher
- Wiley-Blackwell
- external identifiers
-
- pmid:37580016
- scopus:85169511640
- ISSN
- 1469-0691
- DOI
- 10.1016/j.cmi.2023.08.007
- project
- Improved preparedness for future pandemics and other health crises through large-scale disease surveillance
- language
- English
- LU publication?
- yes
- id
- 76df4c4f-5fd6-4e28-a36f-5d624e9f2613
- date added to LUP
- 2023-10-12 15:38:31
- date last changed
- 2025-10-19 05:43:42
@article{76df4c4f-5fd6-4e28-a36f-5d624e9f2613,
abstract = {{<p>OBJECTIVES: Evidence on waning patterns in protection from vaccine-induced, infection-induced, and hybrid immunity against death is scarce. The aim of this study is to assess the temporal trends in protection against mortality.</p><p>METHODS: Population-based case-control study nested in the total population of Scania Region, Sweden using individual-level registry data of COVID-19-related deaths (<30 days after positive SARS-CoV-2 test) between 27 December 2020 and 3 June 2022. Controls were matched for age, sex, and index date. Conditional logistic regression was used to estimate the preventable fraction (PF) from vaccination (PF<br>
vac corresponding to vaccine effectiveness; ≥2 vaccine doses vs. 0 doses), prior infection (PF <br>
inf), and hybrid immunity (PF<br>
hybrid). PF was calculated as one minus odds ratio. Models were adjusted for comorbidities, long-term care facility residence, prior infection (for PF<br>
vac), country of birth, socio-economic conditions, and time since last vaccination (for PF<br>
inf).<br>
</p><p>RESULTS: In total, 14 936 individuals (1440 COVID-19-related deaths and 13 496 controls) were included in the case-control analyses (45% females, median age: 84 years). PF<br>
vac was above 90% during the first month after vaccination, regardless of the number of vaccine doses. After 6 months, PF<br>
vac of two doses waned to 34% (95% CI: -30% to 66%). PF<br>
inf for people surviving a SARS-CoV-2 infection waned from 88% (-16% to 99%) 3 months after infection to 62% (34-79%) after 9 months. No differences in waning patterns in PF<br>
vac were seen between virus variants, gender, and age.<br>
</p><p>DISCUSSION: Given the waning of protection against death, continuous surveillance of population immunity status, particularly among the most vulnerable population groups, could help to further fine-tune vaccination recommendations.</p>}},
author = {{Dietler, Dominik and Kahn, Fredrik and Inghammar, Malin and Björk, Jonas}},
issn = {{1469-0691}},
language = {{eng}},
month = {{08}},
number = {{12}},
pages = {{1573--1580}},
publisher = {{Wiley-Blackwell}},
series = {{Clinical Microbiology and Infection}},
title = {{Waning protection after vaccination and prior infection against COVID-19-related mortality over 18 months}},
url = {{http://dx.doi.org/10.1016/j.cmi.2023.08.007}},
doi = {{10.1016/j.cmi.2023.08.007}},
volume = {{29}},
year = {{2023}},
}