ArticleBMC infectious diseases2021
Haemophilus influenzae type b (Hib) seroprevalence in France: impact of vaccination schedules.
Article in BMC infectious diseases, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.
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Who cites it
16 citing papers in PubMed, 21 citations in OpenAlex.
- Carriage ofVaccines · 2026Review
- Resurgence of invasive Haemophilus influenzae type b disease in France, 2017-2024: epidemiological, genomic, and immunological insights.NPJ vaccines · 2026Article
- Product- and schedule-specific vaccine effectiveness against invasiveEuro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2026Article
- Multi-Antigen Protein Vaccine Confers Protection in a Murine Model Against IntranasalVaccines · 2026Article
- Characteristics of Haemophilus influenzae Isolates Responsible for Invasive Infections in Poland in 2018-2023.Infectious diseases and therapy · 2026Article
- Infant protection from invasiveHuman vaccines & immunotherapeutics · 2025Review
- Epidemiology of Bacterial Meningitis in the Lombardy Region, Italy, from 2014 to 2024: An Observational, Retrospective Study.Microorganisms · 2025Article
- Epidemiology of invasive Haemophilus influenzae infections in Belgium: 2018-2022.European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology · 2025Article
- Article
- Vaccine-preventable Pediatric Acute Bacterial Meningitis in France: A Time Series Analysis of a 19-Year Prospective National Surveillance Network.The Pediatric infectious disease journal · 2024Article
- Population immunity to pneumococcal serotypes in Kilifi, Kenya, before and 6 years after the introduction of PCV10 with a catch-up campaign: an observational study of cross-sectional serosurveys.The Lancet. Infectious diseases · 2023Observational
- Scale-Up of Capsular Polysaccharide Production Process byBioengineering (Basel, Switzerland) · 2022Article
- Changes in InvasiveMicroorganisms · 2022Article
- From Genetics to Epigenetics: Top 4 Aspects for Improved SARS-CoV-2 Vaccine Designs as Paradigmatic Examples.Global medical genetics · 2022Review
- Cellular and Humoral Immune Response to a Third Dose of BNT162b2 COVID-19 Vaccine - A Prospective Observational Study.Frontiers in immunology · 2022Observational
- Increase in invasive disease caused byEuro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin · 2021Article
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Authors and funding
7 authors at 1 institution in 1 country.
Funding
Abstract
backgroundHaemophilus influenzae serotype b (Hib) conjugate vaccine was introduced in France in 1992 as a 3 + 1 scheme at 2, 3, and 4 months (primary vaccination) with a booster at the age of 16-18 months. The vaccination was simplified in 2013 to a 2 + 1 scheme at 2 and 4 months (primary immunization) and a booster at the age of 11 months. The coverage was 95.4% in France at 24 months in 2017. During the period 2017-2019 the number of Hib invasive infections increased with several cases of vaccine failure.
methodsThe numbers and proportions of Hib invasive isolates during the period 2017-2019 were compared and vaccine failure cases were explored. A seroprevalence study was performed by measuring anti-polyribosyl-ribitol phosphate (PRP) IgG concentrations by ELISA among children < 5 years of age at the time of sampling covering the periods of the 3 + 1 or 2 + 1 schemes of Hib vaccination. A collection of residual 232 sera was tested (group 3 + 1 n = 130) and (group 2 + 1, n = 102) was used.
resultsAnti-PRP IgG concentrations were significantly higher in toddlers of 2 years (median 2.9 μg/ml) in the 3 + 1 group while these concentrations showed a median of 0.58 μg/ml among children in 2 + 1 group. The proportion of children of 2 years of age who achieved 1 μg/ml threshold (56%) was higher in the 3 + 1 group than that observed in the 2 + 1 group (25%). All the detected cases of vaccine failure received the 2 + 1 scheme and anti-PRP IgG levels were less than 1 μg/ml at the admission. However, these levels increased significantly 1 month after the admission suggesting a secondary immune response to the Hib infection.
conclusionsThe simplification of the vaccination to a 2 + 1 scheme seems to reduce the level of anti PRP IgG. Hib antibodies wane rapidly after the 11 months booster and may not be enough to ensure long term protection. Surveillance of cases and monitoring of titres need to be continued to inform future vaccination policy.
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