The sandfly fauna, anthropophily and the seasonal activities of Pintomyia spinicrassa (Diptera: Psychodidae: Phlebotominae) in a focus of cutaneous leishmaniasis in northeastern Colombia.

This study was conducted to identify the sandfly fauna and the anthropophilic species in a coffee-growing area of Villanueva, Norte de Santander, Colombia, a focus of American cutaneous leishmaniasis, and to analyse the relationship between the most frequent species and rainfall, relative humidity and temperature, with the aim of contributing to epidemiological surveillance in the area. Sandfly collections were performed fortnightly between February 2006-September 2007 using automatic light traps, Shannon traps, protected human bait and aspiration in resting places. A total of 7,051 sandflies belonging to 12 species were captured. Pintomyia spinicrassa (95.7%) predominated. Pintomyia oresbia and Lutzomyia sp. of Pichinde were found in the state of Norte de Santander for the first time. Pi. spinicrassa, Pintomyia nuneztovari, Micropygomyia venezuelensis, Lutzomyia (Helcocyrtomyia) scorzai and Lu. (Helcocyrtomyia) sp. were captured on the protected human bait. A significant association between Pi. spinicrassa abundance and the total rainfall and the average temperature and humidity 10 days before the collection was observed. The dominance of Pi. spinicrassa, a recognised vector of Leishmania braziliensis, especially during the dry periods, indicates that the risk of parasite transmission may increase.

The sandfly fauna, anthropophily and the seasonal activities of Pintomyia spinicrassa (Diptera: Psychodidae: Phlebotominae) in a focus of cutaneous leishmaniasis in northeastern Colombia

This study was conducted to identify the sandfly fauna and the anthropophilic species in a coffee-growing area of Villanueva, Norte de Santander, Colombia, a focus of American cutaneous leishmaniasis, and to analyse the relationship between the most frequent species and rainfall, relative humidity and temperature, with the aim of contributing to epidemiological surveillance in the area. Sandfly collections were performed fortnightly between February 2006-September 2007 using automatic light traps, Shannon traps, protected human bait and aspiration in resting places. A total of 7,051 sandflies belonging to 12 species were captured. Pintomyia spinicrassa (95.7%) predominated. Pintomyia oresbia and Lutzomyia sp. of Pichinde were found in the state of Norte de Santander for the first time. Pi. spinicrassa, Pintomyia nuneztovari, Micropygomyia venezuelensis, Lutzomyia (Helcocyrtomyia) scorzai and Lu. (Helcocyrtomyia) sp. were captured on the protected human bait. A significant association between Pi. spinicrassa abundance and the total rainfall and the average temperature and humidity 10 days before the collection was observed. The dominance of Pi. spinicrassa, a recognised vector of Leishmania braziliensis, especially during the dry periods, indicates that the risk of parasite transmission may increase.

[Definition of appropriate temperature and storage conditions in the detection of Leishmania DNA with PCR in phlebotomine flies]. / Definición de las condiciones de temperatura y almacenamiento adecuadas en la detección de ADN de Leishmania por PCR en flebotominos.

For epidemiological studies and control programs of leishmaniasis, taxonomic identification of the etiologic agent of the disease in the insect vector is of critical importance. The implementation of molecular techniques such as the polymerase chain reaction (PCR) has permitted great advances in the efficacy and sensitivity of parasite identification. Previously, these investigations involved labor-intensive dissections and required expert personnel. The present work evaluates the effects of storage methods of phlebotomine samples in the optimization of PCR identification of Leishmania. Females of Lutzomyia longipalpis, from the colony of the Instituto Nacional de Salud, were experimentally infected with Leishmania chagasi (= L. infantum), from the upper Magdalena Valley (Quipile, Cundinamarca, Colombia). The infected insects were preserved in three solutions: 100% ethanol, 70% ethanol, and TE; subsamples of each class were stored at -80 degrees C, -20 degrees C and room temperature. To determine infection rates, samples were dissected and screened microscopically. Chelex 100 was used for extraction of total Leishmania DNA. For PCR amplification, the kinetoplastic minicircle DNA primers OL1 and OL2 of Leishmania were used, and the products were visualized by electrophoresis in 1% agarose gels. For each of the 3 storage conditions, amplifications were successful, producing a approximately 120 base pair product unique to Leishmania. The results demonstrated the advantage of PCR as a routine screening method for detecting infected flies in endemic foci of visceral leishmaniasis. Since storage method did not affect PCR amplification success, the most cost effective method -70% ethanol at room temperature--is the option recommended for storing entomological samples in vector incrimination studies.

Definición de las condiciones de temperatura y almacenamiento adecuadas en la detección de ADN de Leishmania por PCR en flebotominos / Definition of appropriate temperature and storage conditions in the detection of Leishmania DNA with PCR in phlebotomine flies

For epidemiological studies and control programs of leishmaniasis, taxonomic identification of the etiologic agent of the disease in the insect vector is of critical importance. The implementation of molecular techniques such as the polymerase chain reaction (PCR) has permitted great advances in the efficacy and sensitivity of parasite identification. Previously, these investigations involved labor-intensive dissections and required expert personnel. The present work evaluates the effects of storage methods of phlebotomine samples in the optimization of PCR identification of Leishmania. Females of Lutzomyia longipalpis, from the colony of the Instituto Nacional de Salud, were experimentally infected with Leishmania chagasi (= L. infantum), from the upper Magdalena Valley (Quipile, Cundinamarca, Colombia). The infected insects were preserved in three solutions: 100 ethanol, 70 ethanol, and TE; subsamples of each class were stored at -80 degrees C, -20 degrees C and room temperature. To determine infection rates, samples were dissected and screened microscopically. Chelex 100 was used for extraction of total Leishmania DNA. For PCR amplification, the kinetoplastic minicircle DNA primers OL1 and OL2 of Leishmania were used, and the products were visualized by electrophoresis in 1 agarose gels. For each of the 3 storage conditions, amplifications were successful, producing a approximately 120 base pair product unique to Leishmania. The results demonstrated the advantage of PCR as a routine screening method for detecting infected flies in endemic foci of visceral leishmaniasis. Since storage method did not affect PCR amplification success, the most cost effective method -70 ethanol at room temperature--is the option recommended for storing entomological samples in vector incrimination studies.

Especies de Lutzomyia (Diptera: Psychodidae) posibles vectores de leishmaniasis en la ciudad de Bucaramanga, Santander, Colombia / Lutzomyia species (Diptera: Psychodidae) possible leishmaniasis vector in the city of Bucaramanga, Santander, Colombia

Debido al registro, en los últimos cinco años, de ciento veinticinco casos urbanos de leishmaniasis cutánea en la ciudad de Bucaramanga, se desarrolló el presente estudio con el fin de determinar las especies del género Lutzomyia existentes en la ciudad y sus implicaciones en salud pública. La búsqueda de los flebotomíneos se hizo en ocho zonas de la ciudad en los meses de septiembre a diciembre de 1996, utilizando como técnicas de muestreo trampas de luz tipo CDC y aspiración directa en cebo humano protegido y en sitios de reposo. Los insectos fueron preservados en alcohol al 70 por ciento y aclarados con KOH y fenol. Se capturaron 212 especímenes pertenecientes a once especies del género Lutzomyia y una del género Brumptomyia. Entre las especies antropofílicas encontradas, L. ovallesi y L. gomezi se destacan por ser reconocidas como vectores de Leishmania braziliensis L. ovallesi fue la especie de mayor distribución en la ciudad, L. gomezi la más abundante en las capturas con cebo humano; las dos se encontraron en barrios donde se ha informado el mayor número de casos de la enfermedad. El hallazgo de estas especies en la ciudad sugiere la posibilidad de que los habitantes de Bucaramanga puedan infectarse en el área urbana y crea la necesidad de continuar estudios que contribuyan a interrumpir el ciclo de transmisión

Strongyloidiasis. Métodos Diagnósticos

La strongyloidiasis se diagnostica rutinariamente por el examen directo de las heces del paciente. Esta no es la mejor ni la única manera de dilucidar la enfermedad, pues actualmente se cuenta con métodos inmunológicos indirectos y técnicas directas más sensibles y confiables que permiten la mayor captación de casos agudos y portadores crónicos de la infección