Effect of pneumococcal vaccine on morbidity from acute lower respiratory tract infections in Papua New Guinean children.

Abstract

The effect of a 14-valent pneumococcal polysaccharide vaccine on morbidity from acute lower respiratory tract infection (ALRI) was determined in a randomized double-blind controlled trial in children under the age of 5 years living in the Paupa New Guinea highlands. The vaccine did not protect against mild ALRI. Vaccine efficacy in the study as a whole was 28% for moderate/severe ALRI, which was not statistically significant though consistent with the significant effect on mortality. Children entered the trial in five separate cohorts 4 months apart. The incidence of disease and vaccine efficacy varied between cohorts and with age. There was no vaccine effect in the first cohort, which had a..