A recent study published in BMJ Thorax highlights significant changes in the landscape of pneumococcal pneumonia among adults hospitalized with community-acquired pneumonia (CAP) over the past decade.
The data, drawn from a prospective cohort of over 5,000 patients, reveals that the proportion of CAP cases caused by pneumococcus has nearly doubled, rising from 36.4% in 2013 to 66.9% in 2023. Notably, serotype 3 has become the dominant strain, increasing from 13.4% to 48.8% during the same period.
Serotype 3 pneumonia was found to be more common in older adults, men, and those with chronic renal disease. However, despite its prevalence, it was not linked to greater disease severity, critical care needs, or higher mortality rates.
These findings raise important questions about the effectiveness of current vaccination strategies, as serotype 3 continues to thrive despite widespread infant immunization programs, suggesting limited herd protection.
