The cost of epidemiological transition: A study of a decrease in pertussis vaccination coverage

Direct costs of programs with the vaccination rate at 90% remained systematically lower than the expected cost of pertussis disease in the case of non prevention. The stability over time of the vaccination coverage at a constant level of 90% made it possible to ensure the largest cost saving strategy during the period of 14 years of analysis. Transitions to programs with a lower proportion of vaccinated children systematically incurred an incremental direct cost for society. The amount of that cost rose with the size of the drop in the new vaccination coverage and diminished, due to the J-curve optimistic effect, when the fall in vaccination rate generated a delayed increase in notification cases of pertussis.