general population study in Spain to assess benefits of 23-valent pneumococcal vaccine (see DOI: 10.1093/cid/ciu002). PPV-23 was recommended for all people over 60 yo. 27,204 people in the cohort were followed prospectively from 2008-2011, of whom 8981 received the vaccine. mean age 72. primary outcome: hospitalization for pneumococcal community-acquired pneumonia (CAP), and all-cause CAP. pneumoccocal etiology determined if pos blood culture, pos sputum culture with no other likely bacterial pathogen, or positive urinary antigen test. results:
–incidence rate (per 1000 person-years) were 0.21 for bacteremic pneumococcal CAP, 1.45 for nonbacteremic pneumococcal CAP, and 7.51 for all-cause CAP. None of these were significantly different between vaccinated and unvaccinated.
–BUT, in those vaccinated within the past 5 years (n=2390) there was a reduced risk of bacteremic pneumococcal CAP (HR=0.38, .09-1.68), nonbacteremic pneumococcal CAP (HR=0.52, .29-.92), overall pneumococcal CAP (HR=0.49, .29-.84), and all-cause CAP (HR=0.75, .58-.98). [the latter 3 were statistically significant]
note: this is not a randomized controlled trial, only an observational study comparing these outcomes in those who elected to take the vaccine vs those who did not, and there were differences between those vaccinated and not (though, not surprisingly, those choosing vaccination were sicker: older, more likely to have chronic pulmonary, heart, liver, or kidney disease and more htn, hyperlipidemia, obesity, smoking, cancer, alcoholism, immunocompromise). but there also may be unknown biases in this type of trial.
pneumococcal vaccine (PPV-23) is somewhat mixed in the studies of effectiveness, with more suggestion that it helps with invasive pneumococcal disease (recent cochrane review suggested vaccine efficacy of 74% for invasive disease). there was initial concern of severe/anaphyllactic reactions if revaccinated soon after a first dose, though subsequent trials indicated that this really did not happen if there was a several-year hiatus. other previous studies have found significant decreases in antibody levels after 3-5 years (and, i must admit, based on those studies, low cost, and apparent lack of toxicity, i have been revaccinating people every 5-6 years all along and have not seen any toxicity in patients receiving 3-4 shots). but it should be stated that this is not the CDC recommendation — for normal risk: one vaccination at age 65. for high risk (age 19-65) revaccinate one time after 5 years, then again at age 65 if at least 5 years after last vaccination,
geoff