Use of pneumonia vaccine in children reduced rates in adults age 65+
Within a year of introduction of PCV7 (7-valent pneumococcal conjugate vaccine) for use in the U.S. in infants, children under 2 years, and high risk children ages 2 to 4; invasive pneumococcal disease rates in unvaccinated individuals age 65 and older fell by 18%.
Whitney, Cynthia G., Monica M. Farley, James Hadler, Lee H. Harrison, Nancy M. Bennett, et al.; for the Active Bacterial Core Surveillance of the Emerging Infections Program Network. Decline in Invasive Pneumococcal Disease After the Introduction of Protein-Polysaccharide Conjugate Vaccine. N Engl J Med. 2003; 348(18): 1737-46. http://www.nejm.org/doi/full/10.1056/NEJMoa022823