Modeling the economic value of a Chagas' disease therapeutic vaccine

Abstract

The health burden of Chagas' disease (resulting from Trypanosoma cruzi infection) in Latin America (estimated to outweigh that of malaria by 5-fold and affect 2-6 million people in Mexico alone) has motivated development of therapeutic vaccines to prevent infection progression to severe disease. Our economic model for a Chagas' therapeutic vaccine in Mexico suggests that a vaccine would be highly cost-effective and in many cases economically dominant (providing both cost savings and health benefits) throughout a range of protection durations, severe adverse event risk, and dosing regimens and would be most likely to provide a positive return on investment if the vaccine prevented (rather than delayed) the onset of cardiomyopathy.

Figure 1. Model structure. (A) Health states. Death from Chagas’ related or other causes could occur at any health state, see Table 1 for mortality probabilities. ^aAll individuals entered the model in the Indeterminate health state (B) Transition probabilities for vaccinated individuals in the indeterminate health state. ^aAll individuals on the “Vaccinate” branch received the first dose of the vaccine. Receipt of subsequent doses was dependent upon compliance and the number of doses in a full vaccine course. ^bIncluded, but not limited to cardiomyopathy