Interpretation criteria : serotypes 1*, 2, 3*, 4*, 5*, 6A*, 6B*, 7F*, 8, 9N, 9V*, 10A, 11A, 12F, 14*, 15B, 17F, 18C*, 19A*, 19F*, 22F, 23F* et 33F.
An anti-pneumococcal vaccine response can be considered as "appropriate" in the presence of 1) antibody titers after vaccination ≥ 0.35 μg / mL ** for at least 50% of the serotypes included in the vaccine and / or 2) an increase in antibody titers ≥ 2 times (before versus after vaccination) for at least 50% of the serotypes included in the vaccine.
It is important to note that IgG antibodies induced following Prevenar 13® immunization correspond to a humoral immune response directed against protein-conjugated antigens. In contrast, IgG antibodies induced following Pneumovax23® immunization correspond to a humoral immune response directed against polysaccharide antigens.
Polysaccharide antigens from the pneumococcal serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F are included in Prevenar 13® vaccine. Polysaccharides antigens from the pneumococcal serotypes 1, 2, 3, 4, 5, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F and 33F are included in Pneumovax23® vaccine.
Polysaccharide antigens from the pneumococcal serotype 6A is only present in Prevenar 13®.
"Natural" anti-pneumococcal humoral immune responses.
In the absence of vaccination, anti-pneumococcal antibodies generated as part of immune responses to "natural" exposures to pneumoccus reflect a humoral immune response directed against polysaccharide antigens. The proportion of serotypes against which antibody titers are found to be ≥ 0.35 μg / mL varies from one individual to another and indicates exposure to one or more pneumococcal serotypes.
Antibodies directed against 22F polysaccharide are not measured by our method.
* Polysaccharides included in Prevenar 13 vaccine.
* *Siber et al., Vaccine 25 (2007) 3816-3826.