[Circulación de Leishmania infantum y Trypanosoma cruzi en perros domésticos de áreas urbanas de Sincelejo, región Caribe de Colombia].

Introducción. La enfermedad de Chagas y la leishmaniasis tradicionalmente se han considerado zoonosis endémicas de áreas rurales del país. Sin embargo, la aparición de casos de estas enfermedades en áreas urbanas sugiere nuevos ciclos de circulación de estos parásitos. Por esta razón, se ha propuesto a los perros como centinelas de estos agentes zoonóticos, dado su rol como huéspedes accidentales o reservorios. Objetivo. Evaluar la circulación silenciosa de Leishmania spp. y Trypanosoma cruzi en perros de zonas urbanas de la ciudad de Sincelejo, Sucre. Materiales y métodos. Se analizaron 100 muestras de sangre de perros para amplificar la región ITS1 de Leishmania spp. Las muestras positivas se utilizaron para amplificar la región conservada del minicírculo del ADN del cinetoplasto de Leishmania infantum y para el análisis de polimorfismos de longitud de fragmentos de restricción con la endonucleasa HaeIII. Por otra parte, se amplificó un fragmento del ADN satelital de T. cruzi. Además, se evaluó la presencia de infecciones por Ehrlichia canis y Anaplasma platys, como potencialmente modificadoras de las manifestaciones clínicas. Resultados. De los 100 perros estudiados, se detectó: Leishmania spp. en 32, T. cruzi en 12, ambos parásitos en 7 y L. infantum en 18. Se encontraron infecciones por anaplasmatáceos en 18, y coinfecciones por bacterias y parásitos en 8 de los perros. En general, 47 de los animales estaban infectados por, al menos, un agente etiológico. Conclusión. Se demuestra la circulación de L. infantum y T. cruzi en zonas urbanas de Sincelejo, así como coinfecciones de estos parásitos junto con parásitos de la familia Anaplasmataceae. El presente estudio demuestra la conveniencia del uso de perros en la vigilancia epidemiológica de estos agentes zoonóticos.

Circulación de Leishmania infantum y Trypanosoma cruzi en perros domésticos de áreas urbanas de Sincelejo, región Caribe de Colombia / Silent circulation of Leishmania infantum and Trypanosoma cruzi among urban dogs from Sincelejo city, Caribbean region of Colombia

Introducción. La enfermedad de Chagas y la leishmaniasis tradicionalmente se han considerado zoonosis endémicas de áreas rurales del país. Sin embargo, la aparición de casos de estas enfermedades en áreas urbanas sugiere nuevos ciclos de circulación de estos parásitos. Por esta razón, se ha propuesto a los perros como centinelas de estos agentes zoonóticos, dado su rol como huéspedes accidentales o reservorios. Objetivo. Evaluar la circulación silenciosa de Leishmania spp. y Trypanosoma cruzi en perros de zonas urbanas de la ciudad de Sincelejo, Sucre. Materiales y métodos. Se analizaron 100 muestras de sangre de perros para amplificar la región ITS1 de Leishmania spp. Las muestras positivas se utilizaron para amplificar la región conservada del minicírculo del ADN del cinetoplasto de Leishmania infantum y para el análisis de polimorfismos de longitud de fragmentos de restricción con la endonucleasa HaelII. Por otra parte, se amplificó un fragmento del ADN satelital de T. cruzi. Además, se evaluó la presencia de infecciones por Ehrlichia canis y Anaplasma platys, como potencialmente modificadoras de las manifestaciones clínicas. Resultados. De los 100 perros estudiados, se detectó: Leishmania spp. en 32, T. cruzi en 12, ambos parásitos en 7 y L. infantum en 18. Se encontraron infecciones por anaplasmatáceos en 18, y coinfecciones por bacterias y parásitos en 8 de los perros. En general, 47 de los animales estaban infectados por, al menos, un agente etiológico. Conclusión. Se demuestra la circulación de L. infantum y T. cruzi en zonas urbanas de Sincelejo, así como coinfecciones de estos parásitos junto con parásitos de la familia Anaplasmataceae. El presente estudio demuestra la conveniencia del uso de perros en la vigilancia epidemiológica de estos agentes zoonóticos.

Introduction: Leishmania infantum and Trypanosoma cruzi are considered endemic zoonotic agents in rural areas of the country; however, there is a high risk of urbanization due to anthropogenic processes. For this reason, dogs have been proposed as sentinels of these zoonoses given their role as patients, hosts and/or reservoirs. Objective: To assess the silent circulation of Leishmania spp. and T. cruzi parasites in canines from urban areas of Sincelejo, Sucre. Materials and methods: One hundred canine blood samples were used to amplify the ITS1 region of Leishmania spp. Positive samples were used to amplify the conserved region of the kinetoplast DNA minicircle of L. infantum and for restriction fragment length polymorphism analysis with HaelII endonuclease. In addition, a satellite DNA of T. cruzi was amplified. Also, the presence of Ehrlichia canis and Anaplasma platys was evaluated as infections that can influence clinical symptoms and health of animals. Results: Leishmania spp. was detected in 32% (32/100) and T. cruzi in 12% (12/100) of the animals, and 7% (7/100) of the samples were positive for both parasites. Also, L. infantum and infections with Anaplasmataceae family parasites were both detected in 18 % (18/100) of the samples. In the same way, co-infections with bacteria and parasites were found in 8 % (8/100) of the animals. Overall, 47 % (47/100) of the animals were infected with at least one agent. Conclusion: The circulation of L. infantum and T. cruzi, as well as co-infections of pathogens of the Anaplasmataceae family, is demonstrated in urban areas of Sincelejo. The present study demonstrates the convenience of canines as epidemiological surveillance sentinels of these zoonotic agents.

[First report of the F1534C mutation associated with cross-resistance to DDT and pyrethroids in Aedes aegypti from Colombia].

INTRODUCTION: The main strategy for the control of Aedes aegypti, vector of dengue, chikungunya and Zika viruses, is based on the use of insecticides to reduce its populations. However, their use has led to insect resistance to these chemicals. Objective: To determine the presence of the F1534C mutation associated with cross-resistance to DDT and pyrethroids in A. aegypti in Sincelejo, Colombia. Materials and methods: We studied nine specimens of A. aegypti that showed resistance to lambdacyhalothrin in bioassays developed by the Secretaría de Salud de Sucre. We used a semi-nested PCR as previously described by Harris, et al., to amplify exon 31 of the para gene of the voltage-dependent sodium channel of A. aegypti. We sequenced, edited, and analyzed PCR products with the MEGA 5 software. Results: We detected the wild and mutant alleles of exon 31 in all of the nine mosquitoes tested, and observed the substitution of thymine for guanine in the nucleotide sequence of the mutant allele, producing a change to UGC in the UUC codon, which led to the replacement of phenylalanine by cysteine in residue 1534 of the protein. Conclusion: The nine mosquitoes analyzed presented a heterozygote genotype for the F1534C mutation, whose phenotypic effect is knockdown resistance (kdr) to DDT and pyrethroids.

Diferencias genéticas entre poblaciones de Aedes aegypti de municipios del norte de Colombia, con baja y alta incidencia de dengue / Genetic differences between populations of Aedes aegypti from municipalities in northern Colombia, with high and low dengue incidence

Introducción. Aedes aegypti es el principal vector del dengue en zonas urbanas. A pesar de su importancia epidemiológica, se desconoce la variabilidad genética de las poblaciones del vector en Colombia. Objetivo. Determinar la variabilidad genética del gen mitocondrial ND4 , que codifica para la subunidad 4 de la enzima NADH-deshidrogenasa, entre poblaciones de Ae. aegypti de los municipios de Sincelejo y Guaranda, donde se registra alta y baja incidencia de dengue, respectivamente. Materiales y métodos. A partir del material genético extraído de 36 hembras de Ae. aegypti , se determinó la secuencia parcial del gen mitocondrial ND4 y se estimaron los parámetros de diversidad de nucleótidos, diversidad haplotípica, estructura genética y flujo de genes entre las poblaciones de Sincelejo y Guaranda. También, se analizó la varianza molecular y se construyó una red haplotípica. Resultados. Se obtuvieron 36 secuencias de nucleótidos de 282 pb; éstas presentaron doce sitios polimórficos y se agruparon en diez haplotipos, dos presentes en ambas poblaciones, tres exclusivos de la población de Sincelejo y cinco de la población de Guaranda. Los estimadores de estructura genética ( F ST =0,15) y de flujo de genes ( Nm =1,40) evidencian diferenciación genética y un limitado intercambio de genes entre las poblaciones. Conclusión. Las poblaciones de Ae. aegypti de Sincelejo y Guaranda son genéticamente divergentes.

Introduction: Aedes aegypti is the principal vector of dengue in urban areas. Despite its epidemiological importance, the genetic variability of Colombian populations of this species is unknown. Objetive: To determine the genetic variability of mitocondrial gene ND4, which codes for subunit 4 of the enzyme NADH deshydrogenase, between populations of Ae. aegypti from municipalities of Sincelejo and Guaranda. The incidences of dengue reported from these two localities are high and low, respectively. Materials and methods: Genetic material extracted from 36 females of Ae. aegypti was used to determine the partial sequence of the mitocondrial gene ND4 as well as to estimate the parameters of nucleotidic and haplotypic diversities, genetic structure and gene flow between the Sincelejo and Guaranda populations. The molecular variance was also analysed and a haplotypic network constructed. Results: In all 36 nucleotide sequences of 282pb were obtained. These presented 12 polymorphic sites and could grouped into 10 haplotypes, two of them present in both populations, three exclusive to the Sincelejo population and five to that of Guaranda. The estimators of genetic structure ( F ST = 0.15) and gene flow ( Nm = 1.40) are both indicative of genetic differentiation and a limited exchange of genes between the populations. Conclusions: The Sincelejo and Guaranda populations of Ae. aegypti are genetically divergent.

Actualización de la distribución de especies del género Haemagogus(Díptera: Culicidae) en la Región Caribe colombiana / Registry and distribution update of the species of the Haemagogus (Diptera: Culicidae) genus in the Caribbean region of Colombia

Introducción. Los mosquitos del género Haemagogus son importantes en salud pública, porque algunas de sus especies han sido involucradas como vectores del virus de la fiebre amarilla en su ciclo selvático. Objetivo. Actualizar la distribución de especies del género Haemagogus en las áreas urbanas y periurbanas de los departamentos de Atlántico y Sucre de la Región Caribe. Materiales y métodos. El material entomológico se recolectó mediante larvitrampas en los departamentos de Atlántico y Sucre, durante los años 2010 y 2011. El 80 % de los ejemplares inmaduros se preservó en alcohol al 70 %; algunos se mantuvieron vivos para obtener series entomológicas. La determinación taxonómica se hizo con las claves y descripciones de Arnell (1973). Resultados. En Atlántico, 2,32 % (871) de los 37.573 Culicidae inmaduros eran larvas del género Haemagogus. En Sucre se recolectaron 44 larvas del mismo género (1,22 % de los 3. 611 culícidos). Las especies del género Haemagogus fueron determinadas o identificadas como Hg. equinus, Hg. anastasionis y Hg. celeste en ambos departamentos. En los dos, la mayor abundancia de especies del género Haemagogus se registró durante los meses de mayor precipitación, de junio a noviembre. Conclusión. Se registra la presencia de Hg. anastasionis, Hg. celeste y Hg. equinus en recipientes artificiales en áreas urbanas y periurbanas de los departamentos de Atlántico y Sucre, y se amplía su distribución en la Región Caribe colombiana.

Introduction: The mosquitoes of the Haemagogus (Williston, 1896) genus are relevant in public health because of the involvement of some species as vectors of yellow fever in its sylvan cycle. Objective: To update the distribution of the species of the Haemagogus genus in urban and periurban areas in the departments of Atlántico and Sucre in the Caribbean region of Colombia. Materials and methods: The entomological material was collected in the departments of Atlántico and Sucre by means of larval traps during 2010 to 2011. Eighty per cent of the immature forms were preserved in 70% alcohol. Some were kept alive for the sake of obtaining entomological series. Taxonomical determination was done with Arnell's keys and description, 1973. Results: In Atlántico, 2.32% of 37.573 immature Culicidae (871) were larvae of the Haemagogusgenus. In Sucre, 44 larvae of the same genus were collected (1.22% of 3.611). The species collected in both regions were Hg. equinus, Hg. anastasionis, and Hg. celeste. The Haemagogus genus was most abundant during the months of heaviest rainfall, from June to November. Conclusion: The presence of Hg. anastasionis, Hg. celeste and Hg. equinus was detected in artificial containers, in urban and periurban areas of Atlántico and Sucre. Their distribution in the Caribbean region of Colombia has widened.

[Genetic differences between populations of Aedes aegypti from municipalities in northern Colombia, with high and low dengue incidence]. / Diferencias genéticas entre poblaciones de Aedes aegypti de municipios del norte de Colombia, con baja y alta incidencia de dengue.

INTRODUCTION: Aedes aegypti is the principal vector of dengue in urban areas. Despite its epidemiological importance, the genetic variability of Colombian populations of this species is unknown. OBJETIVE: To determine the genetic variability of mitocondrial gene ND4, which codes for subunit 4 of the enzyme NADH deshydrogenase, between populations of Ae. aegypti from municipalities of Sincelejo and Guaranda. The incidences of dengue reported from these two localities are high and low, respectively. MATERIALS AND METHODS: Genetic material extracted from 36 females of Ae. aegypti was used to determine the partial sequence of the mitocondrial gene ND4 as well as to estimate the parameters of nucleotidic and haplotypic diversities, genetic structure and gene flow between the Sincelejo and Guaranda populations. The molecular variance was also analysed and a haplotypic network constructed. RESULTS: In all 36 nucleotide sequences of 282 pb were obtained. These presented 12 polymorphic sites and could grouped into 10 haplotypes, two of them present in both populations, three exclusive to the Sincelejo population and five to that of Guaranda. The estimators of genetic structure (FST = 0.15) and gene flow (Nm = 1.40) are both indicative of genetic differentiation and a limited exchange of genes between the populations. CONCLUSIONS: The Sincelejo and Guaranda populations of Ae. aegypti are genetically divergent.

[Registry and distribution update of the species of the Haemagogus (Diptera: Culicidae) genus in the Caribbean region of Colombia]. / Actualización de la distribución de especies del género Haemagogus (Díptera: Culicidae) en la Región Caribe colombiana.

INTRODUCTION: The mosquitoes of the Haemagogus (Williston, 1896) genus are relevant in public health because of the involvement of some species as vectors of yellow fever in its sylvan cycle. OBJECTIVE: To update the distribution of the species of the Haemagogus genus in urban and periurban areas in the departments of Atlántico and Sucre in the Caribbean region of Colombia. MATERIALS AND METHODS: The entomological material was collected in the departments of Atlántico and Sucre by means of larval traps during 2010 to 2011. Eighty per cent of the immature forms were preserved in 70% alcohol. Some were kept alive for the sake of obtaining entomological series. Taxonomical determination was done with Arnell's keys and description, 1973. RESULTS: In Atlántico, 2.32% of 37.573 immature Culicidae (871) were larvae of the Haemagogus genus. In Sucre, 44 larvae of the same genus were collected (1.22% of 3.611). The species collected in both regions were Hg. equinus, Hg. anastasionis , and Hg. celeste . The Haemagogus genus was most abundant during the months of heaviest rainfall, from June to November. CONCLUSION: The presence of Hg. anastasionis, Hg. celeste and Hg. equinus was detected in artificial containers, in urban and periurban areas of Atlántico and Sucre. Their distribution in the Caribbean region of Colombia has widened.

Molecular identification of the parasites causing cutaneous leishmaniasis on the Caribbean coast of Colombia.

All clinical manifestations of leishmaniasis exist in Colombia, the cutaneous form being the most frequent in the department of Sucre, where the Leishmania species associated with cutaneous leishmaniasis (CL) is unknown. This study was carried out to determine which Leishmania species was responsible for CL in Sucre, based on amplification and sequencing of the Cyt b gene. Isolates of Leishmania were obtained after CL diagnosis of eight patients who received attention in several health care centers of the study area. The nucleotide sequences obtained from patients were compared to Leishmania reference strains and six of the isolates identified as Leishmania (Viannia) braziliensis, the remaining two being identified as Leishmania (Viannia) panamensis and Leishmania (Viannia) guyanensis. This represents the first report of the presence of L. (V.) guyanensis on the Caribbean coast of Colombia.

[Natural infection of Lutzomyia cayennensis cayennensis with trypanosomatid parasites (Kinetoplastida: Trypanosomatidae) in Los Montes de Maria, Colombia]. / Infección natural de Lutzomyia cayennensis cayennensis con parásitos tripanosomatídeos (Kinetoplastida: Trypanosomatidae) en los Montes de Maria, Colombia.

The presence of sand flies naturally infected with trypanosomatid parasites was determined in Los Montes de Maria, Colombia, a region considered endemic for visceral and cutaneous leishmaniasis. Phlebotomines were collected using CDC light-traps, and sticky traps soaked with castor oil placed in the peri and intradomestic habitats. Six species of Lutzomyia were morphologically identified among the 159 sand flies captured: Lu. evansi, Lu. cayennensis cayennensis, Lu. trinidadensis, Lu. atroclavata, Lu. gomezi and Lu. dubitans. A DNA band of 800 pb corresponding to the small-subunit ribosomal RNA gene (ssrRNA) of the family Trypanosomatidae was amplified in one pool of nine females of Lu. cayennensis cayennensis. This finding constitutes the first evidence of natural infection of this sand fly species with trypanosomatid parasites in Los Montes de Maria.