Natural infection of Lutzomyia rangeliana (Ortiz, 1952) (Diptera: Psychodidae) with Leishmania in Barquisimeto, Lara State, Venezuela

Pathogens, reservoirs, and vectors involved in the transmission of vector-borne and zoonotic diseases in a Colombian region

The ecology of vector-borne diseases (VBDs) is an important system of great complexity, which involves the knowledge about the pathogens and animal species entailed in maintaining transmission cycles in a given locality, including those that act as vectors and reservoirs for the transmitted pathogens. To understand the ecology of some VBDs, we studied vectors, reservoirs, and pathogens of different VBDs, including dengue, leishmaniasis, Chagas disease, malaria, Zika, and chikungunya in the municipality of La Mesa, Cundinamarca, Colombia, a locality close to the capital, Bogotá. Vectors and mammals were sampled in urban and rural areas between May and August 2019. Molecular analyses were performed for the detection of pathogens in mammals and vectors, and of blood-meal sources in insects. Several vectors and mammals collected in this study have been involved in pathogen transmission cycles or may have a potential role in them. The findings of this study suggest that in the municipality of La Mesa, there are both vector and potential reservoir species, which are or could be implicated in the maintenance of the cycles of vector-borne diseases such as leishmaniasis and Chagas disease. Although arbovirus infections, such as dengue, are reported in the municipality, arbovirus presence was not detected. These findings highlight the importance of ongoing surveillance of vectors and associated control operations in La Mesa, of relevance to other locations where vectors and animal hosts also occur.

FLEBOTOMÍNEOS (PSYCHODIDAE: PHLEBOTOMINAE) EN LA ZONA PERIURBANA DE MONTERÍA (CÓRDOBA- COLOMBIA)

El objetivo de este trabajo fue determinar la diversidad de flebotomíneos (Diptera: Psychodidae) en la zona peri-urbana de Montería, (Córdoba-Colombia). Los especímenes se colectaron en cuatro localidades alrededor de Montería con trampas CDC y aspiradores bucales durante febrero y junio de 2018. Los individuos se fragmentaron y aclararon con lactofenol para su posterior identificación mediante claves taxonómicas especializadas. Se estimó la diversidad con el índice de Shannon-Wiener, las localidades se compararon usando la distancia de Bray-Curtis y se cuantificó la riqueza con los índices de Chao 2 y Jacknife 2. Se identificaron seis especies: Micropygomyia cayennensis, Lutzomyia gomezi, Pintomyia rangeliana, Micropygomyia micropyga, Psathyromyia shannoni y Pintomyia evansi. Los sitios de muestreo fueron similares en cuanto a diversidad. Se concluye que la zona peri-urbana de Montería está habitada por especies generalistas de dípteros de la familia Psychodidae que constituyen un riesgo epidemiológico. La riqueza en el área se ve afectada por las características propias de las especies encontradas.

FLEBOTOMINOFAUNA Y PRIMER REGISTRO DE Lutzomyia aclydifera (DIPTERA: PSYCHODIDAE) EN EL CARIBE COLOMBIANO

Uno de los focos de leishmaniasis más importante de Colombia está en Los Montes de María, Departamento de Bolívar, específicamente en El Carmen de Bolívar. A la fecha están registradas 19 especies del género Lutzomyia, en este departamento, algunas con antecedentes como vectores de Leishmania spp. La presente nota informa la abundancia y la diversidad de la flebotominofauna en la zona rural de El Carmen de Bolívar. Mediante el uso de trampas de CDC, se colectaron 1327 hembras del género Lutzomyia entre enero a noviembre de 2018: Lu. evansi (81 %), Lu. panamensis (15,5 %), Lu. gomezi (2,9 %), Lu. dubitans (0,15 %), Lu. aclydifera (0,07 %), Lu. c. cayennensis (0,07 %), Lu. rangeliana (0,07 %) y Lu. serrana (0,07 %). La mayor abundancia de flebotomíneos se presentó en noviembre y la menor en abril, coincidiendo con los meses de lluvia y sequía, respectivamente; mientras que en enero se presentó la mayor diversidad. En esta investigación sobresalen Lu. evansi, Lu. panamensis y Lu. gomezi por sus antecedentes como vectores de Leishmania en el Departamento de Bolívar y otras regiones del país. Se reporta por primera vez para el Caribe Colombiano la especie Lu. aclydifera, la cual deberá ser vigilada en cuanto a su capacidad vectorial para Leishmania.

Behavioral Aspects of Phlebotomine Sand Flies Associated with a Case of Cutaneous Leishmaniasis in Atlántico, Northern Colombia

After the first autochthonous case of cutaneous leishmaniasis was reported in the Atlántico department in the Caribbean region of Colombia, entomological sampling was conducted in the specific areas where the infection might have occurred. CDC traps were installed inside and outside dwellings in the peri-urban and rural areas of a settlement in the municipality of Luruaco. Sampling was performed during the night with protected human bait, and phlebotomine sand flies were actively sampled from potential diurnal resting sites within dwellings. Ten species of the genus Lutzomyia were identified; Lutzomyia evansi was the dominant species (78%) in the rural and peri-urban areas as well as in the different sampled habitats, followed by Lutzomyia panamensis and Lutzomyia gomezi. There was a 100% household infestation by Lu. evansi, and its indoor mean abundance was 13.3 sand flies/CDC trap/night. The indoor mean abundance of Lu. panamensis and Lu. gomezi was only 0.9 and 0.8 sand flies/CDC trap/night, respectively. Female Lu. evansi were collected with protected human bait, mostly in the peridomestic area, with sustained activity during the night and a slight increase in the activity from 19:00 to 23:00 hours. Of the total sand flies captured in the diurnal resting sites, 73.1% were collected from the walls of bedrooms and corresponded to Lu. evansi, Lutzomyia cayennensis cayennensis, and Lutzomyia trinidadensis. Owing to their vectorial importance, the species on which entomological surveillance should be focused are Lu. evansi, Lu. panamensis, and Lu. gomezi. The biting and resting behavior reported in this study will help guide vector prevention and the control of leishmaniasis within the study area.

Surveillance of phlebotomine fauna and Didelphis marsupialis (Didelphimorphia: Didelphidae) infection in an area highly endemic for visceral leishmaniasis in Colombia

INTRODUCTION

The study of the interaction between the parasite, the vector and the mammalian hosts, including man, allows to understand the behavior of the leishmaniases.

OBJECTIVE

To determine the presence of Lutzomyia species and to detect the Leishmania infection in Didelphis marsupialis in an endemic area for visceral leishmaniasis.

MATERIALS AND METHODS

Phlebotomine fauna and individuals of D. marsupialis were collected with CDC and Tomahawk™ traps, respectively. The species of Lutzomyia were identified using the Young and Duncan key (1994). Ear and tail biopsies and blood samples from D. marsupialis were taken to identify the Leishmania species by amplifying a fragment of the gene associated with the 70 kD heat shock protein.

RESULTS

Seven Lutzomyia species were identified: Lu. evansi, Lu. gomezi, Lu. panamensis, Lu. dubitans, Lu. cayennensis cayennensis, Lu. rangeliana and Lu. trinidadensis. The first three species have epidemiological importance in Colombia because of their implications in the transmission of the Leishmania parasite. Sixty-five tissue samples from 19 D. marsupialis individuals were negative for Leishmania spp.

CONCLUSIONS

The presence of the Lutzomyia species that have been identified as vectors for Leishmania inside and around houses in the village of El Bledo, in El Carmen de Bolívar represents a risk of infection. Furthermore, the presence of Lu. panamensis is reported for first time in El Carmen de Bolívar in Colombia. Although the lack of detection of Leishmania spp. in D. marsupialis samples may suggest that D. marsupialis does not play an important role in the transmission cycle of Leishmania in this region, it is necessary to carry out further longitudinal studies to confirm this hypothesis.

REGISTROS NUEVOS DE ESPECIES DE Lutzomyia (DIPTERA: PSYCHODIDAE) EN EL DEPARTAMENTO DE CESAR, COLOMBIA

<p>El estudio de los insectos asociados a la epidemiología de la leishmaniasis, en la Costa Caribe colombiana, se ha concentrado en los departamentos de Sucre y Córdoba, por consiguiente existe un escaso conocimiento de la fauna de flebotomíneos del resto de la región. En la presente nota se presentan cuatro nuevos registros de <em>Lutzomyia</em> spp., para el departamento de Cesar. Los insectos fueron colectados con dos trampas de luz tipo CDC, equipadas con LED de color azul, en el Balneario Hurtado de la ciudad de Valledupar, Cesar. Se recolectaron en total 50 flebotomíneos, los cuales estuvieron representados por las especies <em>Lutzomyia cayennensis</em> <em>cayennensis</em> (38 %), <em>L. evansi</em> (28 %), <em>L. trinidadensis</em> (14 %), <em>L. venezuelensis</em> (10 %), <em>L. micropyga</em> (6 %) y <em>L. rangeliana</em> (2 %). Como primeros registros para el departamento sobresalen <em>L. evansi</em>, <em>L. venezuelensis</em>, <em>L. micropyga</em> y <em>L. </em><em>rangeliana</em>, con lo que se eleva a ocho el número de especies reportadas hasta la fecha en el Cesar. Entre los nuevos registros se destaca el hallazgo de <em>L. evansi</em>, reconocido vector de <em>Leishmania</em> spp. en la Costa Caribe de Colombia. </p><p><strong>New Records of Species of <em>Lutzomyia</em> (Diptera: Psychodidae) From the Department of Cesar, Colombia</strong></p><p>Studies of the insects associated with the epidemiological cycle of leishmaniasis on the Caribbean coast of Colombia have been focused on the departments of Sucre and Córdoba. The phlebotomine sand fly fauna of the rest of the Caribbean region remains little known. In the present study four species of the genus <em>Lutzomyia</em> are reported from the department of Cesar for the first time. Sand flies were sampled using two CDC light traps with blue color LEDs at Balneario Hurtado, a tourist area in the city of Valledupar. A total of 50 phlebotomine sand flies were collected, of which the species <em>Lutzomyia cayennensis cayennensis</em> (38 % of the sample) and <em>L. trinidadensis</em> (14 %) were already known from the departament. Specimens of <em>L. evansi</em> (28 %), <em>L. venezuelensis</em> (10 %), <em>L. micropyga</em> (6 %) and <em>L. rangeliana</em> (2 %) represent the first records of these species for Cesar, raising the number of known occurrences from the department to eight species. Noteworthy among the new records is the sandfly <em>L. evansi</em>, recognized vector de <em>Leishmania</em> spp. in the Colombian Caribbean coast.</p><p><strong> </strong></p>