Repeat revaccination with 23-valent pneumococcal polysaccharide vaccine among adults aged 55-74 years living in Alaska: no evidence of hyporesponsiveness.
BACKGROUND
Older adults are at highest risk of invasive pneumococcal disease (IPD) and are recommended to receive vaccination with 23-valent pneumococcal polysaccharide vaccine (PPV23). Antibody concentrations decline following vaccination. We evaluated the immunogenicity and reactogenicity of revaccination and repeat revaccination.


METHODS
Adults aged 55-74 years were vaccinated with a 1st to 4th dose of PPV23. Participants were eligible for revaccination if a minimum of 6 years had passed since their last dose of PPV23. Blood collected on the day of vaccination and 30 days later was analyzed by ELISA for IgG to five serotypes. Functional antibody activity was measured using an opsonophagocytic killing (OPK) assay. Reactions to vaccination were documented.


RESULTS
Subjects were vaccinated with a 1st dose (n=123), 2nd dose (n=121), or 3rd or 4th dose (n=71) of PPV23. The post-vaccination IgG geometric mean concentrations (GMCs) were similar among first-time vaccinees and re-vaccinees for all serotypes with the exception of a lower GMC for serotype 1 in re-vaccinees. The post-vaccination OPK geometric mean titers (GMTs) were similar among first-time vaccinees and re-vaccinees with the exception of a higher GMT for serotype 6B in re-vaccinees. Compared to first-time vaccinees, re-vaccinees reported more joint pain (p=0.004), fatigue (p=0.019), headache (p=0.014), swelling (p=0.006), and moderate limitation in arm movement (p=0.025).


CONCLUSIONS
Repeat revaccination with PPV23, administered 6 or more years after the prior dose, was immunogenic and generally well tolerated.
Arctic Investigations Program, Centers for Disease Control and Prevention (CDC), 4055 Tudor Centre Dr., Anchorage, AK 99508, USA. llhammitt@gmail.com
Laura L
LL
Hammitt
Lisa R
LR
Bulkow
Rosalyn J
RJ
Singleton
J Pekka
JP
Nuorti
Kim Boyd
KB
Hummel
Karen M
KM
Miernyk
Carolyn
C
Zanis
Melissa
M
Whaley
Sandra
S
Romero-Steiner
Jay C
JC
Butler
Karen
K
Rudolph
Thomas W
TW
Hennessy
D000368:Aged; D000413:Alaska; D000907:Antibodies, Bacterial / Q000097:blood; D000915:Antibody Affinity; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007117:Immunization, Secondary; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D010587:Phagocytosis; D011008:Pneumococcal Infections / Q000517:prevention & control*; D022242:Pneumococcal Vaccines / Q000009:adverse effects / Q000276:immunology*; D011446:Prospective Studies
C414006:23-valent pneumococcal capsular polysaccharide vaccine; D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D022242:Pneumococcal Vaccines