Peer-reviewed article
Impacts of vaccination, school attendance, and nutrition on SARS-CoV-2 antibody titer in a prospective birth cohort in Brazil.
Moin S Vahora, Otávio Leão, Mariângela Freitas da Silveira, Marlos Rodrigues Domingues, Pedro C Hallal et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined how COVID-19 vaccination, school attendance, and nutritional status affect immune response in seven-year-old Brazilian children from a birth cohort. Vaccinated children had significantly higher antibody titers than unvaccinated children, and longer school enrollment was associated with stronger immune response. Stunted (malnourished) children showed weaker antibody responses to natural infection but not when vaccinated, suggesting vaccination can overcome immune deficits caused by poor nutrition.
Key points
- Vaccinated children had 0.29 optical density titer units higher antibody levels than unvaccinated children
- Each month of school attendance was associated with a 0.15 unit increase in COVID-19 antibody titer
- Stunting was associated with lower COVID-19 titers in unvaccinated children but not in vaccinated children
- Vaccination appears to overcome the negative effects of malnutrition on immune response to COVID-19
Limitations
The study is observational and cannot establish causation. It measures only antibody titer as a proxy for immunity and does not assess clinical outcomes such as infection rates or disease severity.
Abstract
In this study, we examine the association between COVID-19 vaccination and antibody titer and whether this association varies by nutritional status and duration of school attendance using linear regression models applied to seven-year-old children from the 2015 Pelotas (Brazil) Birth Cohort (n = 2956). Antibody titers were 0.29 optical density (OD) titer units higher among vaccinated compared with unvaccinated children (95 % CI: 0.24, 0.34). Duration of school enrollment was associated with increased antibody titer, with each month being associated with a 0.15 unit increase in OD titer (95 % CI: 0.14, 0.16). Stunting was associated with lower COVID-19 titers among unvaccinated children (-0.10, 95 % CI: -0.21,0.004), but not among vaccinated children. Stunted children may have poorer immune responses to natural infection, but vaccination can overcome this deficit. Population-wide follow-up vaccination may be beneficial, particularly prior to school entry and for stunted children to reduce the risk of natural infection.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- COVID-19 vaccination
- Population
- Seven-year-old children from the 2015 Pelotas Birth Cohort in Brazil (n=2956)
Key finding
Vaccinated children had 0.29 OD titer units higher antibody levels than unvaccinated children (95% CI: 0.24, 0.34)