Objective: To estimate the effect of 7-valent pneumococcal conjugate vaccine (PCV7) on rates of pneumonia-related health care utilization and costs in children younger than 2 years.
Design: Retrospective population study.
Setting: Approximately 40 large employers each year, from 1997 to 2004.
Participants: Enrollees in the MarketScan databases collected by Thomson Medstat.
Main exposure: Pneumococcal conjugate vaccine immunization program.
Main outcome measures: Rates of International Classification of Diseases, Ninth Revision-coded hospitalizations and ambulatory visits due to all-cause and pneumococcal pneumonia and their medical expenditures.
Results: Comparing the rates in 2004 with those in the baseline period of 1997 to 1999 among children younger than 2 years, hospitalizations due to all-cause pneumonia declined from 11.5 to 5.5 per 1000 children (52.4% decline; P < .001) and ambulatory visits due to all-cause pneumonia declined from 99.3 to 58.5 per 1000 children (41.1% decline; P < .001). Rates of hospitalizations due to pneumococcal pneumonia declined from 0.6 to 0.3 per 1000 children (57.6% decline; P < .001) and rates of ambulatory visits declined from 1.7 to 0.9 per 1000 children (46.9% decline; P < .001). Projecting from these data to the US population, the total estimated direct medical expenditures for all-cause pneumonia-related hospitalizations and ambulatory visits in young children were reduced from an annual average of $688.2 million during the period of 1997 to 1999 to $376.7 million in 2004 (45.3% decline and approximately $310 million decrease).
Conclusions: In children younger than 2 years, the age group targeted for vaccination, pneumonia-related health care utilization in a privately insured population declined substantially following PCV7 introduction. These results suggest that PCV7 may play an important role in reducing the burden of pneumonia, resulting in major savings in medical care cost.