Anti-pneumococci vaccination: role and indications in the prevention of community acquired infections of the lower respiratory tract.

Objective - The authors had for aim to evaluate the effectiveness and clini cal indications of the anti pneumococcal vaccine. Methods - Seventy one articles were selected after a computerized research including the most recent studies on immunogenicity, all the prospective do uble blind randomized trials, and retrospective studies (case-control and i ndirect cohort studies). The evaluation concerned exclusively non conjugate d vaccine. Results - The immune response was significant among vaccinated patients inc luding elderly ones; antibody response was reduced or absent among immune-c ompromised patients. Only one study among 11 randomized trials concerned th e 23-valent vaccine. According to the results of these trials and of 2 meta -analyses, efficacy in preventing pneumococcal bacteremia and pneumococcal pneumonia is clearly established in young adults (with a response rate reac hing around 80% for vaccine serotypes). Clinical studies in older adults, a dults with risk factors, or immune-compromised adults are inconclusive, usu ally because the number of patients was too small. Retrospective case-contr ol and indirect cohort studies confirmed the clinical efficiency of pneumoc occal vaccination. They showed that pneumococcal vaccination was efficient in 50-80% of the patients to prevent invasive pneumococcal diseases, includ ing in older patients and those with associated diseases, particularly with COPD or cardiovascular diseases. Efficiency was not demonstrated in immune -compromised patients. The vaccine proved safe with a good tolerance. Vacci nation is recommended by the WHO and various advisory national committees i n North America and Europe for elderly patients and those with associated d iseases. (C) 2001 Editions scientifiques et medicales Elsevier SAS.