23-Valent pneumococcal revaccination offers short-term protection for elderly.

2003 APR 2 - (NewsRx.com & NewsRx.net) -- by Maria G. Essig, MS, ELS, senior medical writer - A brief but significant immune response was obtained in frail elderly adults by revaccination with a 23-valent pneumococcal polysaccharide vaccine if given at least 5 years after the primary vaccination, according to a report in the Journal of the American Geriatrics Society.

Thomas E. Lackner and colleagues at the University of Minnesota and Johns Hopkins University administered a primary pneumococcal polysaccharide vaccine (PPV) to 67 elderly adults (older than 65 years) who resided in six skilled nursing facilities in the Minneapolis area. At least 5 years later the subjects were revaccinated with a 23-valent PPV, and investigators measured levels of IgG antibodies specific for serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F at 1 and 12 months postvaccination.

One month after revaccination, all IgG antibody levels were significantly higher than baseline, but by 12 months only antibodies against serotypes 6B and 18C remained above baseline levels.

"One month after revaccination, the mean increase in antibody concentration over baseline was significantly greater than 1.4-fold for six of the seven serotypes and the aggregate," reported Lackner and his collaborators. "However, the increase was not significantly greater than 1.4 at one year for any of the serotypes or the aggregate."

The subjects tolerated the vaccine well, with only minor adverse reactions occurring in 11.3% (Pneumococcal polysaccharide revaccination: Immunoglobulin G seroconversion, persistence, and safety in frail, ...