Revaccination with a 23-Valent Pneumococcal Polysaccharide Vaccine Induces Elevated and Persistent Functional Antibody Responses in Adults Aged ⩾65 Years

摘要: BACKGROUND: Older adults are at high risk of developing invasive pneumococcal disease, but the optimal timing and number vaccine doses needed to prevent disease among this group unknown. We compared revaccination with 23-valent polysaccharide (PN23) primary vaccination for eliciting initial persistent functional antibody responses. METHODS: Subjects aged > or = 65 years were enrolled. Functional (opsonic) total immunoglobulin (Ig) G levels measured following either PN23 (n 60) 3-5 after receiving a first 60). Antibody against serotypes 4, 14, 23F was prevaccination (day 0), 30 days vaccination, 5 vaccination. RESULTS: By day 30, both induced significant increases in opsonic IgG levels. Day slightly lower not significantly different than those Year similar groups remained higher subjects. There good agreement between postvaccination CONCLUSIONS: Revaccination older comparable inducing elevated