Related Experiment Videos
[Reflections on the effectiveness of the new combined vaccines]
1Hôpital d'enfants Armand Trousseau, Paris.
Insights
Combination vaccines improve coverage but may affect immunogenicity. New PRP-T and acellular pertussis vaccines show lower antibody levels, impacting infant immunization recommendations.
Area of Science:
- Vaccinology
- Immunology
- Pediatric Infectious Diseases
Context:
- Combination vaccines simplify immunization schedules and enhance vaccine uptake.
- Recent vaccine combinations, particularly involving Haemophilus Influenzae type b (PRP-T) and pertussis vaccines, have raised concerns about immunogenicity.
Purpose:
- To evaluate the immunogenicity of novel combination vaccines, specifically the interference between PRP-T and pertussis components.
- To assess the impact of whole-cell versus acellular pertussis vaccines on anti-PRP antibody levels in combination vaccines.
Summary:
- While pertussis antibody interference is minimal, PRP-T vaccines combined with whole-cell pertussis show antibody levels linked to protective efficacy.
- PRP-T vaccines combined with acellular pertussis vaccines result in lower anti-PRP antibody levels, with fewer children achieving protective titers (>1 mcg/ml).
- These specific combinations are currently not recommended for primary infant immunization in France.
Impact:
- Highlights the need for extensive comparative trials to validate immunogenicity and efficacy of new vaccine combinations.
- Suggests that the number of components in future combination vaccines may be limited to ensure clinical efficacy.
- Informs current vaccination policies and future vaccine development strategies to maintain public health protection.
Abstract:
The combination vaccines are very useful to reduce the number of contacts required to immunize a child fully and to improve the vaccine coverage. Recently the new combinations between Haemophilus Influenzae vaccine (PRP-T) and pertussis vaccines in D-T-P (IVP) combined vaccines have suggested interferences with immunogenicity for PRP-T vaccines. The interference for pertussis antibodies is not significative. The depression of antiPRP antibodies is shown with the whole-cell pertussis vaccine, but the level of antibodies is related to a good protective efficacy. Inversely, when PRP-T vaccine is combined with acellular pertussis vaccines, the antibodies levels are lower, especially the number of children with a level higher than 1 mcg/ml. At the present time, these combinations between PRP-T vaccines and acellular pertussis vaccines are not recommended for primary immunization in infants in France. Such constations emphasize the necessity to perform wide comparative trials to test immunogenicity for all the next combinations between old and new vaccines. A decrease in immunogenicity of combination vaccines is acceptable as long as protective efficacy is preserved. It is possible that the growing number of new vaccines to combine will be limited to keep a clinical efficacy.