Burden of vaccine-preventable pneumococcal disease in hospitalized adults: A Canadian Immunization Research Network (CIRN) Serious Outcomes Surveillance (SOS) network study

In total, 4769 all-cause CAP cases and 81 cases of IPD (non-CAP) were identified. Of the 4769 all-cause CAP cases, a laboratory test for S. pneumoniae was performed in 3851, identifying 14.3% as CAPSpn. Of CAP cases among whom all four diagnostic test were performed, S. pneumoniae was identified in 23.2% (144/621). CAPSpn cases increased with age and the disease burden of illness was evident in terms of requirement for mechanical ventilation, intensive care unit admission, and 30-day mortality. Of serotypeable CAPSpn or IPD results, predominance for serotypes 3, 7F, 19A, and 22F was observed. The proportion of hospitalized CAP cases caused by a PCV13-type S. pneumoniae ranged between 7.0% and 14.8% among cases with at least one test for S. pneumoniae performed or in whom all four diagnostic tests were performed, respectively. Overall, vaccine-preventable pneumococcal CAP and IPD were shown to be significant causes of morbidity and mortality in hospitalized Canadian adults in the three years following infant PCV13 immunization programs in Canada.