In 1999, in the .Hospital del Niño.. a new case of visceral leishmaniasis was identified in a 2 years old child from Taipiplaya in the Caranavi district. For this reason, a visceral leishmaniasis evaluation using serological and molecular tests was realized on 122 healthy people and also on one leishmania cutanea infected person. Leishmania spp was present in 32,3 % of the studied people and 14,4 % had an anti-rk39 antibody, attesting the existence of Leishmania chagasi responsible for visceral leishmaniasis. The possibility of mixed infections with other Leishmania species as well as mixed infections Leishmania spp and Trypanosama cruzi, responsible for chagas disease should not be discarded

En 1999, en el Hospital del Niño se registró un nuevo caso de Leishmaniasis visceral sobre un niño de dos años proveniente del cantón de Taipiplaya (Provincia Caranavi). Por este motivo se realiza en este cantón una evaluación transversal de la leishmaniasis visceral mediante pruebas serológicas y moleculares involucrando a 122 inpiduos clínicamente sanos y un inpiduo con infección positiva a Leishmania cutánea, Se demostró la circulación de Leishmania sp. en 32,3% de sujetos estudiados. El 14,4% de la población examinada presentó anticuerpos anti-rk39, demostrándose la circulación de Leishmania chagasi responsable de la leishmaniasis visceral. No podemos descartar la posibilidad de la existencia de coinfecciones mixtas inter-especie de Leishmania como también de coinfecciones mixtas por Leishmania sp y Trypanosoma cruzi, responsable de la enfermedad de Chagas

En 1999, en el Hospital del Niño se registró un nuevo caso de Leishmaniasis visceral sobre un niño de dos años proveniente del cantón de Taipiplaya (Provincia Caranavi). Por este motivo se realiza en este cantón una evaluación transversal de la leishmaniasis visceral mediante pruebas serológicas y moleculares involucrando a 122 individuos clínicamente sanos y un individuo con infección positiva a Leishmania cutánea, Se demostró la circulación de Leishmania sp. en 32,3% de sujetos estudiados. El 14.4% de la población examinada presentó anticuerpos anti-rk39, demostrándose la circulación de Leishmania chagasi responsable de la leishmaniasis visceral. No podemos descartar la posibilidad de la existencia de coinfecciones mixtas inter-especie de Leishmania como también de coinfecciones mixtas por Leishmania sp. y Trypanosoma cruzi, responsable de la enfermedad de Chagas.

In 1999, in the "Hospital del Niño". a new case of visceral leishmaniasis was identified in a 2 years old child from Taipiplaya in the Caranavi district. For this reason, a visceral leishmaniasis evaluation using serological and molecular tests was realized on 122 healthy people and also on one leishmania cutanea infected person. Leishmania spp was present in 32,3 % of the studied people and 14,4 % had an anti-rk39 antibody, attesting the existence of Leishmania chagasi responsible for visceral leishmaniasis. The possibility of mixed infections with other Leishmania species as well as mixed infections Leishmania spp and Trypanosama cruzi, responsible for chagas disease should not be discarded.

A sylvatic Triatoma infestans DM (dark morph) population detected in the Bolivian Chaco was characterized and compared with various domestic ones. The degree of differentiation of DM was clearly within the T. infestans intra-specific level. Nevertheless marked chromatic and morphometric differences as well as differences in antennal pattern, chromosome banding and randomly amplified polymorphic DNA support the hypothesis of a distinct population. Continuous exchange of insects between wild and domestic habitats seems unlikely in the Chaco.

The restriction fragment length polymorphism of the 195 bp repeated DNA sequence of Trypanosoma cruzi was analyzed among 23 T. cruzi stocks giving a reliable picture of the whole phylogenetic variability of the species. The profiles observed with the enzymes Hinf I and Hae III were linked together and supported the existence of two groups. Group 1 shows a 195 bp repeated unit (Hinf I) and high molecular weight DNA (Hae III), while group 2 presents a ladder profile for each enzyme, which is a characteristic of tandemly repeated DNA. The two groups, respectively, clustered stocks pertaining to the two principal lineages evidenced by isoenzyme and RAPD markers. The congruence among these three independent genomic markers corroborates the existence of two real phylogenetic lineages in T. cruzi. The specific monomorphic profiles for each major phylogenetic lineage suggest the existence of ancient sexuality and cryptic biological speciation.