Vaccine · 2026
Spike antibody levels and risk of SARS-CoV-2 reinfection: a two-year cohort study in previously infected adults.
СтатьяНазвание и аннотация: Перевод пока не подготовлен
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Wiwe Elias Frost, Jørgensen Mona, Brandt Lisbeth, Talouzi Nessrin, Roed Casper, Harboe Zitta Barrella, Fischer Thea Kølsen, Hansen Young Bae Lee, Hillig Thore
Аннотация
BACKGROUND: The need for a validated correlate of protection (CoP) for SARS-CoV-2 remains unmet, particularly in immunosuppressed or vulnerable populations. Antibody quantification is widely available, but the relationship with reinfection risk remains uncertain.
METHODS: We conducted a two-year cohort study in Denmark including 2960 adults with previous SARS-CoV-2 infection and more than 9000 plasma samples collected between 2020 and 2022. Spike antibody concentrations were measured using the Roche Elecsys® Anti-SARS-CoV-2 S assay. Weekly antibody levels were modelled by nonlinear mixed-effect models and linked to reinfection risk using a competing-risk Cox regression explicitly adjusted for infection pressure and individual testing frequency.
FINDINGS: Among 1600 participants with longitudinal antibody follow-up, 133 reinfections were observed during a median of 22 weeks at risk. Each tenfold (log10) increase in spike antibody level was associated with a 28 % reduction in reinfection hazard (HR 0.72, 95 % CI 0.57-0.90, p = 0.0045). This effect was consistent across multiple sensitivity analyses and robust to fluctuations in infection pressure and testing practices. No discrete antibody threshold was identified, suggesting a continuous, dose-response association between antibody concentration and protection.
INTERPRETATION: Higher spike antibody levels were consistently associated with lower risk of SARS-CoV-2 reinfection, supporting their use as continuous markers of protection. Although assay-specific and without a single protective cutoff, antibody measurements may help monitor patient groups prone to poor vaccine responses-such as those receiving chemotherapy or immune-modulating drugs-and guide individualized revaccination once immune competence recovers.
METHODS: We conducted a two-year cohort study in Denmark including 2960 adults with previous SARS-CoV-2 infection and more than 9000 plasma samples collected between 2020 and 2022. Spike antibody concentrations were measured using the Roche Elecsys® Anti-SARS-CoV-2 S assay. Weekly antibody levels were modelled by nonlinear mixed-effect models and linked to reinfection risk using a competing-risk Cox regression explicitly adjusted for infection pressure and individual testing frequency.
FINDINGS: Among 1600 participants with longitudinal antibody follow-up, 133 reinfections were observed during a median of 22 weeks at risk. Each tenfold (log10) increase in spike antibody level was associated with a 28 % reduction in reinfection hazard (HR 0.72, 95 % CI 0.57-0.90, p = 0.0045). This effect was consistent across multiple sensitivity analyses and robust to fluctuations in infection pressure and testing practices. No discrete antibody threshold was identified, suggesting a continuous, dose-response association between antibody concentration and protection.
INTERPRETATION: Higher spike antibody levels were consistently associated with lower risk of SARS-CoV-2 reinfection, supporting their use as continuous markers of protection. Although assay-specific and without a single protective cutoff, antibody measurements may help monitor patient groups prone to poor vaccine responses-such as those receiving chemotherapy or immune-modulating drugs-and guide individualized revaccination once immune competence recovers.