Early humoral and cellular responses after bivalent SARS‐CoV‐2 mRNA‐1273.214 vaccination in long‐term care and retirement home residents in Ontario, Canada: An observational cohort study
Bibliographic record
Abstract
Abstract Immunogenicity of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) bivalent mRNA‐1273.214 vaccine (Original/Omicron B.1.1.529 [BA.1]) is underreported in vulnerable older adults in congregate care settings. In residents of 26 long‐term care and retirement homes in Ontario, Canada, humoral (i.e., serum anti‐spike and anti‐receptor binding domain [anti‐RBD]) IgG and IgA antibodies and live SARS‐CoV‐2 neutralization) and cellular (i.e., CD4 + and CD8 + activation‐induced marker spike‐specific T cell memory) responses were assessed 7–120 days postvaccination with four monovalent mRNA vaccines ( n = 494) or subsequent bivalent mRNA‐1273.214 vaccination (fifth vaccine) ( n = 557). Within 4 months, anti‐spike and anti‐RBD antibody levels were similar after monovalent and bivalent vaccination in infection‐naïve individuals. Hybrid immunity (i.e., vaccination and natural infection) generally increased humoral responses. After bivalent vaccination, compared to monovalent vaccination, residents with hybrid immunity had elevated anti‐spike and anti‐RBD IgG and IgA antibodies. Omicron BA.1 antibody‐mediated neutralization, and CD8 + T cell memory responses to the Omicron BA.1 spike protein, were also higher after bivalent vaccination. Humoral and cellular responses were, therefore, noninferior within 4 months of bivalent mRNA‐1273.214 vaccination compared to monovalent mRNA vaccination. Waning of humoral but not cellular immunity was particularly evident in individuals without hybrid immunity. Continued monitoring of vaccine‐associated and hybrid immunity against emerging Omicron variants of concern is necessary to assess longevity of protection.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".