October 10, 1994

Immunogenicity of Pneumococcal Revaccination in Patients With Chronic Disease

Author Affiliations

From the Arctic Investigations Program, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska (Drs Davidson, Parkinson, and Lanier and Mss Bulkow and Chamblee); the Department of Medicine, Alaska Native Medical Center, Anchorage (Drs Davidson and Grabman); the Division of Immunization, National Center for Preventive Services, Centers for Disease Control and Prevention, Atlanta, Ga (Dr Williams); and the Department of Microbiology and Immunology, State University of New York Health Science Center at Brooklyn (Dr Schiffman). Dr Davidson is now with the Department of Medicine, Alaska Native Medical Center, Anchorage. Dr Lanier is now with the Alaska Area Native Health Service, Anchorage.

Arch Intern Med. 1994;154(19):2209-2214. doi:10.1001/archinte.1994.00420190111013

Background:  To prevent serious pneumococcal infections, 23-valent pneumococcal polysaccharide vaccine is recommended for individuals over 24 months of age with chronic predisposing diseases and for healthy older adults. This nonrandomized controlled study in rural Alaska assessed the immunogenicity of revaccination in adults.

Methods:  Twenty-six adults, 33 to 88 years of age, vaccinated a mean of 7.4 years before this study, were matched to 26 previously unvaccinated subjects by age, number of chronic diseases, sex, and ethnicity. One or more chronic diseases were validated in 62% of subjects (32 of 52). All received a first or second intramuscular dose of pneumococcal vaccine. Antibody levels were determined by radioimmunoassay for 12 pneumococcal capsular serotypes immediately before and 20 to 84 days after vaccination.

Results:  Six to 9 years after primary vaccination, over one third of serotype-specific antibody levels were below 500 ng of antibody nitrogen per milliliter, equal to the percentage in unvaccinated subjects of similar age. Antibody levels against all pneumococcal serotypes rose to similar levels after primary vaccination and revaccination, and 54% and 55%, respectively, of subjects who received primary vaccination and revaccination had at least a 1.4-fold increase in antibody levels. Only the antibody level for serotype 4 remained low. Neither gender nor age affected peak response. For those with chronic diseases, there was a trend toward fewer low antibody levels against three or more serotypes after revaccination (two subjects [13%]) than after primary vaccination (five subjects [31%]).

Conclusions:  Following the initial immunization of highrisk and elderly patients with pneumococcal polysaccharide, pneumococcal antibody levels appear to wane with time. Primary vaccination and revaccination 6 or more years after a first dose of pneumococcal vaccine stimulate comparable mean antibody levels.(Arch Intern Med. 1994;154:2209-2214)