Evaluation of Meningococcal Serogroup C Bactericidal Antibodies after Primary Vaccination: A Multicentre Study, Italy
- PMID: 35632534
- PMCID: PMC9144765
- DOI: 10.3390/vaccines10050778
Evaluation of Meningococcal Serogroup C Bactericidal Antibodies after Primary Vaccination: A Multicentre Study, Italy
Abstract
Here, we evaluated over time in different cohorts of children vaccinated against serogroup C Neisseria meningitidis, the presence of antibodies with neutralizing activity. A total of 348 sera samples of enrolled children by year since vaccination (<1 year- up to 5 years), starting from February 2016 to December 2017, were collected in three collaborating centers. Meningococcal serogroup C (MenC) antibody titers were measured with a serum bactericidal antibody (SBA) assay using rabbit complement (rSBA) following standard operating procedures. The cut-off of rSBA titer ≥ 8 is considered the correlate of protection. We observed a significantly declining of bactericidal rSBA titers by 23% every year, for every 1-year from vaccination (Adjusted PR = 0.77, 95% CI: 0.71−0.84). The proportions of children with bactericidal antibodies, immunized with the meningococcal serogroup C conjugate (MCC) vaccine, declined from 67.7% (95% CI: 48.6−83.3%) one year after vaccination, to 36.7% (95% CI: 19.9−56.1%) five years after vaccination (chi-square for linear trend, p < 0.001). Children vaccinated with the tetravalent meningococcal serogroup ACWY vaccine resulted in a high proportion of bactericidal rSBA MenC titer ≥ 1:8 (90.6%, 95% CI: 79.3−96.9%) after a mean time of seven months. Overall, the results provide some evidences on the evaluation of meningococcal serogroup C bactericidal antibodies after primary vaccination.
Keywords: Neisseria meningitidis; bactericidal antibody; meningococcal conjugate vaccine.
Conflict of interest statement
The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.
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References
-
- Istituto Superiore Di Sanità ISS Surveillance Data on Invasive Bacterial Diseases, Consolidated Report 2019. [(accessed on 20 April 2022)]. Available online: https://www.iss.it/-/rapporto-consolidato-mib-2019.
-
- PNPV 2005–2007. [(accessed on 20 April 2022)]; Available online: http://www.salute.gov.it/imgs/C_17_pubblicazioni_543_allegato.pdf.
-
- PNPV 2012–2014. [(accessed on 20 April 2022)]; Available online: http://www.salute.gov.it/imgs/C_17_pubblicazioni_1721_allegato.pdf.
-
- PNPV 2017-2019. [(accessed on 20 April 2022)]; Available online: http://www.salute.gov.it/imgs/C_17_pubblicazioni_2571_allegato.pdf.
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