Immunologic memory 5 years after meningococcal A/C conjugate vaccination in infancy.
Infant vaccination with meningococcal conjugates may provide long-term protection against disease. Antibody levels and immunologic memory were assessed in 5-year-old Gambian children who received meningococcal A/C conjugate vaccination (MenA/C) in infancy. At 2 years, they were randomized to receive a booster of MenA/C (conjugate group), meningococcal A/C polysaccharide (MPS group), or inactivated polio vaccine (IPV group). All groups were revaccinated with 10 microg MPS at 5 years of age, as were 39 previously unvaccinated age-matched control subjects. Before revaccination, titers were higher in the conjugate and MPS groups than in control subjects (P<.001); titers for the IPV group were similar to those for control subjects. Ten days after revaccination, the conjugate and IPV groups had similar serogroup C serum bactericidal antibody titers (3421 vs. 2790, respectively). These levels were significantly higher than those in the MPS (426) and control (485) groups (P<.001). Thus, immunologic memory was sustained for > or =5 years; however, MPS challenge at 2 years interfered with a subsequent memory response.
MacLennan
J
J
Oxford Vaccine Group, Dept. of Pediatrics, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom. jenny.maclennan@ceid.ox.ac.uk
Obaro
S
S
Deeks
J
J
Lake
D
D
Elie
C
C
Carlone
G
G
Moxon
E R
ER
Greenwood
B
B
D000328:Adult; D000907:Antibodies, Bacterial / Q000097:blood; D002675:Child, Preschool; D005714:Gambia; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary; D007156:Immunologic Memory; D007223:Infant; D008585:Meningitis, Meningococcal / Q000517:prevention & control; D022401:Meningococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D009345:Neisseria meningitidis / Q000276:immunology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D014611:Vaccination; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology
D000907:Antibodies, Bacterial; D022401:Meningococcal Vaccines; D011135:Polysaccharides, Bacterial; D018074:Vaccines, Conjugate