10 research outputs found
Long-lasting hyporesponsivenss induced by the 23-valent pneumococcal polysaccharide vaccine (PPV23) in asplenic patients with beta-thalassemia major
We have previously shown that multiple vaccinations with 23-valent
pneumococcal polysaccharide vaccine (PPV23s) resulted in attenuated
antibody responses to subsequent 7-valent conjugate vaccine (PCV7) in
asplenic adults with beta-thalassemia major (Orthopoulos et al. Vaccine
2009; 27:350). However, there is evidence that PPV23-induced immune
hyporesponsiveness could be overcome with time (Papadatou et al. Clin
Infect Dis 2014; 59:862).
In the current study we investigate the duration of hyporesponsiveness
in the same cohort seven years after the original study vaccinations.
Patients received one dose of 13-valent conjugate vaccine (PCV13) and
antibody levels were measured before and one month after vaccination.
Antibodies increased significantly after vaccination with PCV13, but
were lower than post-PCV7 seven years earlier. Lower pre-vaccination
antibody levels were associated with more robust response to PCV13.
Our findings suggest that PPV23 should be used cautiously in asplenic
adults vaccinated with multiple PPV23s in the past. Measurement of
anti-pneumococcal antibodies before and after vaccination could be used
to optimise timing of vaccinations and certify vaccine immunogenicity in
such individuals. (C) 2015 Elsevier Ltd. All rights reserved