Cost-effectiveness of the introduction of the pneumococcal polysaccharide vaccine in elderly Colombian population.

BACKGROUND: Streptococcus pneumoniae causes community-acquired pneumonia, otitis media and meningitis, with higher incidences at the extremes of life. PPV-23 vaccine is widely used in prevention of pneumonia and invasive pneumococcal disease in older adults in developed countries. We developed an evaluation of cost-effectiveness of implementing PPV-23 in Colombian population over 60 years.

METHODS: The number of cases of pneumonia and meningitis in patients over 60 years and the proportion by S. pneumoniae was estimated based on a review of literature. A decision tree model with a 5-year time horizon was built to evaluate the cost-effectiveness of the implementation of the PPV-23 in this population. Direct health care costs of out- and in-patients were calculated based on expenditure records from the Bogota public health system. Incremental cost-effectiveness ratios per life saved and per year of life gained were estimated based on the decision tree model. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS: Without vaccination 4460 (range 2384-8162) bacteremic pneumococcal pneumonias and 141 (range 73-183) pneumococcal meningitis would occur among people over 60 years old in Colombia. In the first year, vaccination with PPV-23 at US$8/dose would save 480 (range 100-1753) deaths due to Invasive and non-invasive pneumococcal disease. Vaccination would results in US$3400/deaths averted (range US$1028-10,862) and US$1514/life years gained (range US$408-5404).

CONCLUSION: Vaccination with PPV-23 in over 60 years is a highly cost-effective public health measure in Colombia. Despite some limitations, the results are robust, and may help developing countries to perform informed decisions about the introduction of the vaccine.