The Amazon II: Leishmaniasis and Chagas Diseases

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Chagas disease and leishmaniasis are the most important vector-borne protozoan NTDs. Almost all of the 8-9 million cases of Chagas disease (with approximately 50,000 new cases annually) occur in poor rural and, increasingly, many new urban and peri-urban areas of Latin America. Of these cases, an estimated 5.4 million people will develop chronic Chagas heart disease, while 900,000 will develop megaesophagus and megacolon. In LAC, the burden of disease caused by Trypanosoma cruzi infection is between five to ten times greater than malaria. Chagas disease is disproportionately represented among people living in poverty. The disease has also emerged or re-emerged in areas of conflict in Chiapas State, Mexico and Colombia. The major approaches to control including improved case management and vector control programs, together with housing improvement through regional programs. In LAC, both cutaneous and visceral forms of leishmaniasis result primarily from zoonotic transmission from either canine or sylvatic reservoir hosts. The most important determinants for the emergence of both new world zoonotic cutaneous leishmaniasis (ZCL) and zoonotic visceral leishmaniasis (ZVL) include poverty, urbanization, and human migration. Leishmania mexicana, L. amazonensis, L. braziliensis, L panamensis, L. peruviana, and L. guyanensis are the major species that cause new world ZCL. Approximately 62,000 cases of ZCL occur primarily in Brazil, Colombia, and Venezuela, where urbanization near Lutzomyia sandfly breeding sites have led to an increase in the number of cases. In addition, the emergence of ZCL n Colombia is linked to several decades of armed and guerilla internal conflict fueled by cocaine production and trafficking. In northeastern Brazil, ZVL (L. chagasi) has become an important infection in the favelas of Forteleza, Salvador do Bahia, and other urban centers; ZVL has also emerged in Rio de Janeiro and Belo Horizonte. A regional leishmaniasis control action plan is now being implemented.