Streptococcus pneumoniae continues to cause a substantial burden of disease and death in adults, despite nearly 100 years of research into disease prevention and the availability of a licensed vaccine. To date, uptake of the vaccine has generally been limited to older adults and those with chronic illness in high income countries. Coverage has been generally suboptimal, perhaps because of the continued controversy about the vaccine’s efficacy against various clinical end points and within different populations.

In the linked randomised controlled trial (doi:10.1136/bmj.c1004), Maruyama and colleagues assess the effects of the 23-valent pneumococcal polysaccharide vaccine in 1006 nursing home residents in Japan.1 This is the first trial of this type for many years, and the first to show that this vaccine protects against all cause pneumonia (vaccine efficacy 44.8%, 95% confidence interval 22.4 to 60.8) and pneumococcal pneumonia (vaccine efficacy 63.8%, 32.1 to 80.7) in older adults.

Pneumonia is the most common presentation of pneumococcal disease in adults, and it was outbreaks of pneumococcal pneumonia in …