In the per-protocol analysis of first episodes of infections due to vaccine-type strains , community-acquired pneumonia occurred in @ persons in the PCV@ group and @ persons in the placebo group ( vaccine efficacy , @ % ; @ % confidence interval -LSB- CI -RSB- , @ to @ ) , nonbacteremic and noninvasive community-acquired pneumonia occurred in @ persons in the PCV@ group and @ persons in the placebo group ( vaccine efficacy , @ % ; @ % CI , @ to @ ) , and invasive pneumococcal disease occurred in @ persons in the PCV@ group and @ persons in the placebo group ( vaccine efficacy , @ % ; @ % CI , @ to @ ) .