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COVID-19 seroprevalence changes over time, with infection, vaccination, and waning immunity. Seroprevalence estimates are needed to determine when increased COVID-19 vaccination coverage is needed, and when booster doses should be considered, to reduce the spread and disease severity of COVID-19 infection. We use an age-structured model including infection, vaccination and waning immunity to estimate the distribution of immunity to COVID-19 in the Canadian population. This is the first mathematical model to do so. We estimate that 60–80% of the Canadian population has some immunity to COVID-19 by late Summer 2021, depending on specific characteristics of the vaccine and the waning rate of immunity. Models results indicate that increased vaccination uptake in age groups 12–29, and booster doses in age group 50+ are needed to reduce the severity COVID-19 Fall 2021 resurgence.
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This content will become publicly available on April 1, 2026
Basic reproduction numbers for infection and vaccination age epidemic models
The basic reproduction number R_0 for an infection age and vaccination age structured epidemic model is investigated. The connection of R_0 to the infection age transmission rate and the vaccination age immunization rate is analyzed. The model emphasizes the importance of pre-symptomatic infectiousness and vaccination efficacy. The model is applied to the COVID–19 epidemic in New York State.
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- Award ID(s):
- 2421378
- PAR ID:
- 10603875
- Publisher / Repository:
- American Institute of Mathematical Sciences
- Date Published:
- Journal Name:
- Numerical Algebra, Control and Optimization
- Volume:
- 0
- Issue:
- 0
- ISSN:
- 2155-3289
- Page Range / eLocation ID:
- 0 to 0
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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