In children, Prevnar is extremely effective, according to data from the U.S. Centers for Disease Control and Prevention. In a study of 37,000 infants in California, the initial version of the vaccine, Prevnar 7, reduced the incidence of pneumococcal disease, a major cause of death in children, by 90 percent.
Since the U.S. began routinely vaccinating children against pneumococcal disease, the incidence of invasive disease due to the strains of the bacteria included in Prevnar 7 decreased 99 percent, states the CDC. A small increase in the number of cases due to strains not included in Prevnar 7 has declined since the introduction of its successor, Prevnar 13.
In adults over 65, Prevnar 13 is 75 percent effective in preventing invasive pneumococcal disease and 45 percent effective in preventing pneumonia, according to the CDC. The latest version of the vaccine, Pneumovax 23, which has 23 serotypes, has an overall efficacy of between 50 and 80 percent.
Pneumococcal disease is an illness caused by the bacterium Streptococcus pneumoniae, states Medical News Today. It causes pneumonia, meningitis and blood infections, which costs many people their lives. As of Aug. 3, 2015, the price of the Prevnar 13 vaccine is about $152 per dose, while the cost of Pneumovax 23 is about $72 says the CDC.