Objective Characterize the foci of visceral leishmaniasis infection in Neiva with a clinical and epidemiological approach. Materials and Methods Six children consulted medical services with hepatosplenomegaly. They were found to have anemia and leukopenia. The diagnosis was performed by bone marrow (five patients) and spleen (1 patient) aspiration. An active search for cases was carried out in the community. Anti-Leishmania infantum antibodies were also sought out using indirect immunofluorescence (IIF) in symptomatic patients and in dogs (IFI, rK39). House calls were made in order to carry out educational activities and to collect disease vectors. Patients received miltefosine, amphotericin B or Glucantime®. Results LV was confirmed in seven children. In six of them, the bone marrow or spleen aspirate contained amastigotes. The IIF was positive in 4 patients and negative in 3. One child was detected throught the active community search, confirmed by the clinic with IIF (1:32). Six patients were cured with liposomal amphotericin B (o deoxycholate) and one patient was cured with Glucantime®. The canine seroprevalence in 1182 dogs was 6.1% (IFI and rK39); the positive animals were destroyed. L. longipalpis was found in the houses. This is the principal vector of LV in Colombia. Conclusions The study showed that two zones of Neiva have children infected with LV. Diagnostic confirmation must include aspiration of bone marrow and IIFs. Treatment with miltefosine was not helpful, but liposomal amphotericin B is an ideal therapy. To control LV, active case searching, community education and vector and reservoir control is necessary.

Objetivo Estudiar clínica y epidemiológicamente focos de leishmaniasis visceral (LV) urbana en Neiva (Colombia). Materiales y Métodos Seis niños consultaron por hepato-esplenomegalia. Presentaban anemia y leucopenia. Se realizó biopsia por aspiración de medula ósea (5 pacientes) y de bazo (1 paciente). Se hizo búsqueda activa de casos en la comunidad y de anticuerpos anti-Leishmania infantum por inmunofluorescencia indirecta (IFI) en los sintomáticos y en reservorios caninos (IFI, rK39). Se hicieron visitas domiciliarias para educación comunitaria y búsqueda de vectores. Los pacientes recibieron Miltefosina, Anfotericina B o Glucantime®. Resultados Se confirmó LV en siete niños. En seis, el aspirado de medula ósea o bazo demostró amastigotes. La IFI fue positiva en 4 pacientes y negativa en 3. Un niño se detectó por búsqueda activa comunitaria, con clínica de LV, confirmada por IFI (1:32). La miltefosina no fue útil en 6 de los 7 casos. La Anfotericina B liposomal o deoxicolato, curó 6 pacientes y el Glucantime® uno. La seroprevalencia en 1182 caninos (IFI y rK39) fue de 6.1 %; los animales positivos fueron sacrificados. Se demostró Lu. longipalpis, vector de LV, en el peridomicilio. Conclusiones Demostramos LV urbana en dos comunas de Neiva. La confirmación diagnóstica incluyó aspiración de medula ósea e IFI. La Miltefosina no fue útil. La Anfotericina B liposomal fue la terapia ideal. Para controlar la LV es necesario hacer BAC, educación comunitaria, control de vectores y reservorios.

Objetivo Estudiar clínica y epidemiológicamente focos de leishmaniasis visceral (LV) urbana en Neiva (Colombia). Materiales y Métodos Seis niños consultaron por hepato-esplenomegalia. Presentaban anemia y leucopenia. Se realizó biopsia por aspiración de medula ósea (5 pacientes) y de bazo (1 paciente). Se hizo búsqueda activa de casos en la comunidad y de anticuerpos anti-Leishmania infantum por inmunofluorescencia indirecta (IFI) en los sintomáticos y en reservorios caninos (IFI, rK39). Se hicieron visitas domiciliarias para educación comunitaria y búsqueda de vectores. Los pacientes recibieron Miltefosina, Anfotericina B o Glucantime®. Resultados Se confirmó LV en siete niños. En seis, el aspirado de medula ósea o bazo demostró amastigotes. La IFI fue positiva en 4 pacientes y negativa en 3. Un niño se detectó por búsqueda activa comunitaria, con clínica de LV, confirmada por IFI (1:32). La miltefosina no fue útil en 6 de los 7 casos. La Anfotericina B liposomal o deoxicolato, curó 6 pacientes y el Glucantime® uno. La seroprevalencia en 1182 caninos (IFI y rK39) fue de 6.1 %; los animales positivos fueron sacrificados. Se demostró Lu. longipalpis, vector de LV, en el peridomicilio. Conclusiones Demostramos LV urbana en dos comunas de Neiva. La confirmación diagnóstica incluyó aspiración de medula ósea e IFI. La Miltefosina no fue útil. La Anfotericina B liposomal fue la terapia ideal. Para controlar la LV es necesario hacer BAC, educación comunitaria, control de vectores y reservorios.

Objective Characterize the foci of visceral leishmaniasis infection in Neiva with a clinical and epidemiological approach. Materials and Methods Six children consulted medical services with hepatosplenomegaly. They were found to have anemia and leukopenia. The diagnosis was performed by bone marrow (five patients) and spleen (1 patient) aspiration. An active search for cases was carried out in the community. Anti-Leishmania infantum antibodies were also sought out using indirect immunofluorescence (IIF) in symptomatic patients and in dogs (IFI, rK39). House calls were made in order to carry out educational activities and to collect disease vectors. Patients received miltefosine, amphotericin B or Glucantime®. Results LV was confirmed in seven children. In six of them, the bone marrow or spleen aspirate contained amastigotes. The IIF was positive in 4 patients and negative in 3. One child was detected throught the active community search, confirmed by the clinic with IIF (1:32). Six patients were cured with liposomal amphotericin B (o deoxycholate) and one patient was cured with Glucantime®. The canine seroprevalence in 1182 dogs was 6.1% (IFI and rK39); the positive animals were destroyed. L. longipalpis was found in the houses. This is the principal vector of LV in Colombia. Conclusions The study showed that two zones of Neiva have children infected with LV. Diagnostic confirmation must include aspiration of bone marrow and IIFs. Treatment with miltefosine was not helpful, but liposomal amphotericin B is an ideal therapy. To control LV, active case searching, community education and vector and reservoir control is necessary.

Triatoma venosa presents a restricted geographical distribution in America and is considered as a secondary vector of Chagas disease in Colombia and Ecuador. A total of 120 adult insects were collected in domestic and peridomestic habitats in an endemic area of the department of Boyacá, Colombia, in order to determine their genetic structure through morphometric and molecular techniques. The head and wings of each specimen were used for the analyses of size, shape, and sexual dimorphism. A significant sexual dimorphism was found, although no differences in size among the studied groups were detected. Differences were found in the analyzed structures except for male heads. DNA was extracted from the legs in order to carry out the internal transcriber space-2 (ITS-2) amplification and the randon amplified polymorphic DNA (RAPD) analyses. Length polymorphisms were not detected in the ITS-2. Fst and Nm values were estimated (0.047 and 3.4, respectively). The high genetic flow found among the insects captured in the domicile and peridomiciliary environment does not permit a genetic differentiation, thus establishing the peridomicile as an important place for epidemiological surveillance.

Triatoma venosa es uno de los principales vectores secundarios de la enfermedad de Chagas en Colombia. Para estudiar su estructura genetica se colectaron 30 individuos adultos de T. venosa en los municipios de Somondoco (veredas de Cabrera y Barreras), Guateque (veredas de Llano Grande, Tincachoque, y Cantoras) y Sutatenza (veredas de Sisquique, Ovejeras, el Gaque y Piedra Larga), departamento de Boyaca, provenientes de dos habitats diferentes (peridomestico y domestico). El ADN genomico de cada individuo se amplified por RAPD utilizando 4 iniciadores, los productos se visualizaron mediante electroforesis en geles de poliacrilamida al 6% tenidos con plata. Al realizar un analisis mediante el programa SYNTAX 2000 y RAPDPLOT se obtuvo un dendrograma donde no se define un cluster para cada poblacion de insectos evaluada. Al analizar la matriz de datos con RAPDFST se obtuvo un Fst de Wright de 0,047 y de Weir & Cockerham de 0,056. La tasa efectiva de migracion en este analisis fue de 5,0 con la metodologia de Wright, y de 4,2 con la de Weir & Cockerham. Estos resultados preliminares indican una gran movilidad de los insectos entre los dos habitats y un elevado flujo genetico que no permite el establecimiento de diferenciacion genetica entre las poblaciones domesticas y peridomesticas analizadas.

Triatoma venosa is one of the main secondary vectors of Chagas Disease in Colombia. To study its genetic structure, 30 adult individuals of T. venosa were collected in the municipalities of Somondoco (villages of Cabrera and Barreras), Guateque (villages of Llano Grande, Tincachoque, and Cantoras) and Sutatenza (villages of Sisquique, Ovejeras, el Gaque and Piedra Larga) department of Boyaca, from two different habitats (peridomestic and domestic). Genomic DNA of each individual was amplified by RAPD using 4 primers; the products were visualized after polyacrilamide gel electrophoresis followed by 6% silver staining. The dendrogram obtained after analysis with SYNTAX 2000 and RAPDPLOT software did not define a cluster for each insect population evaluated. When the binary matrix was analyzed with RAPDFST software, the Wright's Fst was 0,047 and Weir & Cockerham's Fst was 0,056. The effective migration rate in this analysis was 5,0 under Wright's methodology and 4,2 under Weir & Cockerham's methodology. These preliminary results indicate a high mobility of the insects between the two habitats and a high genetic flow, which do not allow the establishment of genetic differentiation between the domestic and peridomestic populations analyzed.

Con el fin de estudiar la estructura genética de poblaciones silvestres, peridomésticas y domésticas de Triatoma dimidiata se empleó la técnica de amplificación azarosa de polimorfismos de ADN (RAPD). Se calculó el grado de flujo genético existente entre las poblaciones para estimar el riesgo epidemiológico que representan las poblaciones no domiciliadas en la transmisión de la enfermedad de Chagas. Se analizaron 14 individuos silvestres, 10 individuos peridomésticos y 15 domésticos. Se obtuvo un Fst de Wright de 0.071 que denota que hay poca diferenciación genética, y una tasa efectiva de migración (Nm) de 3.3 que indica que por lo menos 3 individuos migran por generación. Estos hallazgos sugieren que las poblaciones no domiciliadas de T. dimidiata representan un riesgo epidemiológico en la transmisión de la enfermedad de Chagas dado que pueden colonizar las viviendas. Por lo tanto deben plantearse: la vigilancia epidemiológica no sólo de la población domiciliada sino también de la peridomiciliada; nuevas y mejores alternativas de control encaminadas a los reservónos en el peridomicilio, y un programa de educación permanente de las personas en riesgo de adquirir la enfermedad.

In order to study the genetic structure of sylvatic, peridomestic and domestic populations of Triatoma dimidiata, we used the randomly amplified polymorphic DNA (RAPD) technique. The genetic flow among populations was estimated to determine the epidemiológica! risk of nondomiciliated populations in the transmission of Chagas disease. Fourteen sylvatic, 10 peridomestic and 15 domestic insects were analyzed. The estimated Wright 's Fst was 0.071 showing low genetic differentiation and an effective migration rate Nm of 3.3 suggesting a movement of at least tnree individuáis per generation. These findings suggest that nondomiciliated populations of T. dimidiata represent an epidemiológica! menace for the transmission of Chagas disease, due to their ability to colonize dwelling. It is necessary to perform: an epidemiológica! surveillance not only of the domestic populations but also on the peridomestic ones. It is also important to carry out new and better control alternatives for reservoirs, and to offer a permanent education program to people at risk of infection.