Seasonal Trends in Pneumococcal Carriage in COPD Patients

Patients suffering from chronic obstructive pulmonary disease (COPD) commonly get exacerbations of their illness which have many potential triggers including infection. The most common cause of lung infection/pneumonia is an organism named Streptococcus pneumoniae. In Ireland a 13-valent pneumococcal conjugated vaccine (PCV-13) was recently introduced into the childhood vaccination programme. This study aims to investigate the carriage rate of S. pneumoniae in COPD patients over one year and to determine if isolates of S. pneumoniae found within the COPD population would be covered by the PCV-13 vaccine.

This study aims to determine the potential contribution of S. pneumoniae to the morbidity of patients with COPD in Ireland and if the PCV-13 has potential for reducing infective exacerbations in this cohort. A group of 150 COPD patients are being monitored at quarterly intervals over one year. At each study visit patients report changes to COPD-related medication, recent hospitalisations and exacerbations and provide a sputum sample (or pharyngeal swab if not possible) which is assessed for the presence of S. pneumoniae. The specific objectives of the study are: 1. To monitor the carriage rate of pneumococci in a cohort of Irish patients with COPD during and outside periods of acute exacerbation over a one year period. 2. To assess the COPD exacerbation rate amongst this group of patients. 3. To monitor changes in the proportion of patients positive for pneumococci carriage over a full season and to document those patients intermittently or permanently colonised. 4. To characterise S. pneumoniae isolates carried by COPD patients in terms of their genetic evolution, comparison with strains in other countries, and antimicrobial susceptibility. 5. To assess the proportion of colonised COPD patients that would be covered by current and future pneumococcal vaccines.