Leishmaniasis in Brazil. XIX: Visceral leishmaniasis in the Amazon Region, and the presence of Lutzomyia longipalpis+ on the Island of Marajo, Para State

Abstract

Sporadic cases of visceral leishmaniasis in Amazonian Brazil appear limited to Pará State, in the lower Amazon valley and principally near the Atlantic coast. The fox Cerdocyon thous (L.) has been incriminated as a natural host of the causative parasite, Leishmania donovani chagasi, but past doubts have existed over the identification of the most likely vector as Lutzomyia (Lutzomyia) longipalpis (Lutz & Neiva, 1912). Investigations on two of five recent cases of visceral leishmaniasis of man in the Districts of Cachoeira do Arari and Salvaterra, on the eastern part of the Island of Marajó, Pará showed undoubted Lu. longipalpis to be abundant in one house and in numerous chicken-houses. This is the first record of Lu. longipalpis on Marajó Island, and the finding supports previous implication of this sandfly in the epidemiology of visceral leishmaniasis in other parts of Pará. Morphological differences have been noted between this insect from Marajó and other specimens from more highly endemic regions in the States of Ceará and Minas Gerais, Brazil.

Ecology of the Leishmania Species in the Guianan Ecoregion Complex

“…It was found naturally infected in Pará 81,125 and experimental transmission was demonstrated. 126 Rates of infection support the suggestion that this canid, which is commonly associated with forested or wooded areas, may represent the primitive natural host of L. 81,113 Although foxes are shy animals, they often invade farms and houses of rural areas in search of food. Since no infections were detected in a large number of rodents and marsupials, it has been proposed that an enzootic may be maintained in foxes by a sylvatic population of Lu.…”

“…111 This vector may exist as a species complex with different genetic profiles and biologic properties. [112][113][114][115][116][117] Lutzomyia longipalpis is typically a peri-domestic phlebotomine sand fly in dry regions. American visceral leishmaniasis has not been associated with forested regions.…”

“…80 This vector is abundantly found in houses, farm buildings and chicken coops, where it feeds on a wide variety of domestic animals, especially chickens and dogs. 113,[118][119][120] It appears to be the ideal vector for a synanthropic zooanthroponosis. However, this vector is usually not markedly anthropophilic and is generally more attracted to dogs, which are considered the main reservoir host of the parasite.…”

Breeding structure of the sand fly Lutzomyia longipalpis (Lutz & Neiva) in Brazil.

“…[4][5][6][7] In this region, VL causes more than 16,000 new clinical infections annually and fatalities are common especially among children. More than 90% of the VL cases reported from Latin America are in Brazil.…”

Sandfly pheromones: Their biology and potential for use in control programs

“…It is also the vector of cutaneous and atypical cutaneous leishmaniasis in Brazil, the rest of South America and Central America (Lainson & Rangel, 2005). In South America L. longipalpis has a wide but discontinuous distribution from Southern Mexico to Northern Argentina and inhabits a wide range of biotypes from the Andes to sea level (Young & Duncan, 1994) and from semi-arid to the lower Amazon basin (Lainson et al, 1983) within the rural, peri-urban and urban environment. It feeds on a wide range of host domesticated animals including dogs, pigs, chickens, goats, cattle as well native animals including the presumed natural host Cerdocyon thous, the South American fox.…”