Revaccination of High-Risk Adults With Pneumococcal Polysaccharide Vaccine

Re-vaccinating adults with the pneumococcal polysaccharide vaccine appears to be safe. This vaccine is used to protect people from infection with Streptococcus pneumoniae. Elderly people in particular are at high risk of this infection. However, after vaccination, blood levels of protective antibodies decline over time, prompting some doctors to re-vaccinate people. A 1999 study found that people who were re-vaccinated were more likely to develop a reaction at the injection site compared to those being vaccinated for the first time. However, the reaction was minor and did not last long.