American leishmaniasis epidemiology in Brazil

Abstract

We have tried to demonstrate in this paper that visceral and cutaneous leishmaniasis are a great public health problem in Brazil. In relation to visceral leishmaniasis, the recognition of new foci denotes the increasing spread of endemic areas, but the areas of highest importance are located mainly at the northeastern region. It calls attention to its suburban character in cities like Sao Luis, Teresina and Rio de Janeiro. L. longipalpis is the only vector known for the disease in domiciliary environment. The dog constitutes the main source for L.d. chagasi, while canids such as Dusicyon velulus and Cerdocyon thous have epidemiological roles. Other vectors for this parasite remain yet as unknown in the enzootic and sylvatic cycles.Cutaneous leishmaniasis have a distribution in almost all the States of Brazil and, at least, two epidemiological patterns exist. The first, corresponds to the classic form of man entering in contact with the agent in virgin forests, like the Amazonian forest and so, there is a permanent risk for epidemics. The second, refers to the occurrence of this disease in areas after forest devastation as in the State of Sao Paulo and in other southeastern States. There are three nosological entities for the cutaneous leishmaniasis in Brazil, their agents being L.m. amazonensis, L. guyanensis and L.b. braziliensis. Five sandfly species have been incriminated as the main vectors in the transmission of the disease in different localities. They are P. flaviscutellatus, P. umbratilis, P. welcomei, P. whitmani and P. intermedius. As for the main natural reservoir of cutaneous leishmaniasis, it remains unknown the one relative to L.b. braziliensis.Resume-Au cours de nos travaux sur la leishmaniose viscerale et cutanee, il devient evident qu'elles representent un grand probleme de sante publique au Bresil nonobstant que se vraie prevalence soit encore ignoree.En ce qui concerne a la leishmaniose viscerale, la decouverte de nouveaux foyers denote l'acroissement de la distributions des surfaces endemiques. Cependant, les plus considerables se trouvent, surtout, a la region nord-est. On signe aussi le caractere suburbain de cette maladie aux villes de Sao Luiz, Teresina et Rio de Janeiro. La Lutzomyia longipalpis est l'unique vecteur connu de cette maladie avec un habitat domiciliaire. Le chien reste le principal reservoir de la Leishmania donovani chagasi mais d'autres especes de canin, tels que le Dusicyon vetulus et le Cerdocyon thous ont un role epidemiologique secondaire. Au cycle biologique sylvestre, les vecteurs restent encore inconnus.Les leishmanioses cutanees sont repandues par presque tous les etats bresilens et ainsi done, deux patrons epidemiologiques de la maladie ont ete classifies: le premier, fait rapport a la forme classique par laquelle Thome peut l'acquerir, e'est-a-dire, au contact avec l'agent, a l'Amazonie, ayant comme resultat um risque permanent d'epidemie. Le deuxiene fait egard a l'occurrence de la maladie aux regions de forets entierment devastees aux Etats de Sao Paulo et d'au...