The potential economic value of a cutaneous leishmaniasis vaccine in seven endemic countries in the Americas

Abstract

Cutaneous leishmaniasis (CL) and its associated complications, including mucocutaneous leishmaniasis (MCL) and diffuse CL (DCL) have emerged as important neglected tropical diseases in Latin America, especially in areas associated with human migration, conflict, and recent deforestation. Because of the limitations of current chemotherapeutic approaches to CL, MCL, and DCL, several prototype vaccines are in different states of product and clinical development. We constructed and utilized a Markov decision analytic computer model to evaluate the potential economic value of a preventative CL vaccine in seven countries in Latin America: Bolivia, Brazil, Colombia, Ecuador, Mexico, Peru, and Venezuela. The results indicated that even a vaccine with a relatively short duration of protection and modest efficacy could be recommended for use in targeted locations, as it could prevent a substantial number of cases at low-cost and potentially even result in cost savings. If the population in the seven countries were vaccinated using a vaccine that provides at least 10 years of protection, an estimated 41,000-144,784 CL cases could be averted, each at a cost less than the cost of current recommended treatments. Further, even a vaccine providing as little as five years duration of protection with as little as 50% efficacy remains cost-effective compared with chemotherapy; additional scenarios resembling epidemic settings such as the one that occurred in Chaparral, Colombia in 2004 demonstrate important economic benefits.

Figure 1

Cutaneous Leishmaniasis Model Structure, a. Health States, b. Uninfected Health State, c. Cutaneous Leishmaniasis Health State, d. Prior Infection Health State, e. Mucocutaneous or Diffuse Leishmaniasis Health State.

Figure 2

Cost per Cutaneous Leishmaniasis (CL) Case Averted. (doses=2, vaccine cost= $0.5/dose, duration of protection = 5 years, compliance with full vaccine regimen = 100%, revaccination = 100%).