The potential of dengue infection is of prime public health concern in tropical and subtropical countries. In Colombia, the management of this disease is based mainly on epidemiological monitoring and vector control. This study, covering the period 2015-2022, adds to this approach by investigating a tool that identifies dengue risk zones considering its environmental and sociodemographic determinants. For this purpose, an analytical, comparative, ecological study was carried out in three stages: i) selection of indicators associated with the occurrence of dengue through hierarchical analysis; ii) execution of a spatial-based Ordinary Least Squares (OLS) regression technique; and iii) multi-criteria analysis of the risk data obtained. Consequently, two optimal models, one for the rainy season (R2=0.5761; AIC=366.3929) and the other for the dry season (R2=0.8560; AIC=440.7557) were obtained for the Dengue Incidence Rate (DIR) during the study period mainly based on socio-demographic and environmental variables. A dengue risk map was generated, showing the impact on three neighbourhoods in the municipality of Piamonte in the Cauca Department covering both seasons. In conclusion, the dengue risk map made it possible to identify highrisk areas and also to identify the determinants of disease occurrence, which can contribute to improving disease management in tropical and subtropical regions.

Aedes aegypti mosquitoes are the main vector of human arbovirosis in tropical and subtropical areas. Their adaptation to urban and rural environments generates infestations inside households. Therefore, entomological surveillance associated with spatio-temporal analysis is an innovative approach for vector control and dengue management. Here, our main aim was to inspect immature pupal stages in households belonging to municipalities at high risk of dengue in Cauca, Colombia, by implementing entomological indices and relating how they influence adult mosquitos' density. We provide novel data for the geographical distribution of 3,806 immature pupal stages of Ae. aegypti. We also report entomological indices and spatial characterization. Our results suggest that, for Ae. aegypti species, pupal productivity generates high densities of adult mosquitos in neighbouring households, evidencing seasonal behaviour. Our dataset is essential as it provides an innovative strategy for mitigating vector-borne diseases using vector spatial patterns. It also delineates the association between these vector spatial patterns, entomological indicators, and breeding sites in high-risk neighbourhoods.

Dengue is an arbovirus transmitted by mosquitoes of the genus Aedes and is one of the 15 main public health problems in the world, including Colombia. Where limited financial resources create a problem for management, there is a need for the department to prioritize target areas for public health implementation. This study focuses on a spatio-temporal analysis to determine the targeted area to manage the public health problems related to dengue cases. To this end, three phases at three different scales were carried out. First, for the departmental scale, four risk clusters were identified in Cauca (RR ≥ 1.49) using the Poisson model, and three clusters were identified through Getis-Ord Gi* hotspots analysis; among them, Patía municipality presented significantly high incidence rates in the time window (2014–2018). Second, on the municipality scale, altitude and minimum temperature were observed to be more relevant than precipitation; considering posterior means, no spatial autocorrelation for the Markov Chain Monte Carlo was found (Moran test ˂ 1.0), and convergence was reached for b1–b105 with 20,000 iterations. Finally, on the local scale, a clustered pattern was observed for dengue cases distribution (nearest neighbour index, NNI = 0.202819) and the accumulated number of pupae (G = 0.70007). Two neighbourhoods showed higher concentrations of both epidemiological and entomological hotspots. In conclusion, the municipality of Patía is in an operational scenario of a high transmission of dengue.

Los mosquitos Aedes aegypti son el principal vector de las arbovirosis humanas en zonas tropicales y subtropicales. Su adaptación a entornos urbanos y rurales genera infestaciones en el intradomicilio de las viviendas. De aquí que, la vigilancia entomológica en asociación con el análisis espacial y el análisis espacio-temporal sean un enfoque innovador para el control de vectores y la gestión del dengue.El objetivo principal de la investigación fue realizar una comparación de la vigilancia entomológica, mediante el uso de índices cuantitativos de pupas y de adultos en tres municipios de alto riesgo de dengue Patía (El Bordo), Miranda y Piamonte del departamento del Cauca, con el fin de examinar cómo influye la productividad de pupas, entre índices entomológicos, en la densidad de mosquitos adultos y otros patrones espaciales y temporales. Ae. aegypti , sus índices entomológicos y su caracterización espacial. Los resultados sugieren que, para las especies de Ae. aegypti , la productividad de pupas genera altas densidades de adultos en las viviendas vecinas, evidenciando un comportamiento estacional.Estos resultados son de gran importancia ya que proporciona una estrategia innovadora para la mitigación de enfermedades transmitidas por vectores utilizando patrones espaciales de los vectores y su asociación con indicadores entomológicos y lugares de cría en barrios de alto riesgo para la transmisión del dengue.

Vector-borne diseases are responsible for more than 17% of human cases of infectious diseases. In most situations, effective control of debilitating and deadly vector-bone diseases (VBDs), such as malaria, dengue, chikungunya, yellow fever, Zika and Chagas requires up-to-date, robust and comprehensive information on the presence, diversity, ecology, bionomics and geographic spread of the organisms that carry and transmit the infectious agents. Huge gaps exist in the information related to these vectors, creating an essential need for campaigns to mobilise and share data. The publication of data papers is an effective tool for overcoming this challenge. These peer-reviewed articles provide scholarly credit for researchers whose vital work of assembling and publishing well-described, properly-formatted datasets often fails to receive appropriate recognition. To address this, GigaScience's sister journal GigaByte partnered with the Global Biodiversity Information Facility (GBIF) to publish a series of data papers, with support from the Special Programme for Research and Training in Tropical Diseases (TDR), hosted by the World Health Organisation (WHO). Here we outline the initial results of this targeted approach to sharing data and describe its importance for controlling VBDs and improving public health.

This study evaluated the effect of Calcium hydroxide (Ca(OH)2 Mg(OH)2) on third stages Pi. evansi larvae mortality under experimental laboratory conditions. Three treatments containing a mixture of phlebotomine natural breeding soil (substrate) and Calcium hydroxide at different concentrations were used: Treatment 1 (T1), 1 kg of substrate mixed with 56.2 g of lime; Treatment 2 (T2), 1 kg of substrate mixed with 62.5 g of lime; and Treatment 3 (T3), 1 kg of substrate mixed with 70 g of lime. in addition, a sample of substrate without lime was used as a control for each treatment. The mortality in T1 was 1% at 24 h and 12% at 48 h, reaching a maximum of 56% at 72 h of exposure. For T2, mortality was progressive, starting with 12% at 12 h, 36% at 24 h, 52% at 48 h, and 100% at 72 h; while T3 showed mortality percentages of 94% and 100% between 12 and 24 h of exposure. Therefore, T3 was the most effective to according to the Kaplan-Meier survival analysis. This study showed that treatments over 62 g of Calcium hydroxide per 1 kg of substrate offer a starting point for immature stage control under laboratory conditions. With these results, we propose to evaluate the cost-effectiveness and feasibility of the application, of the latter concentration, under field conditions in urban environments for its application in vector control programs.

The Culicidae family has two of the most important disease vector genus: Aedes spp. and Culex spp. Both of these are involved in the transmission of arboviruses. Here, we provide novel data for the geographical distribution of 2,383 specimens in the Culicidae family. We also report the percentage of houses infested with these vectors, and Shannon and Simpson diversity indices in three municipalities located in Cauca, Colombia. This dataset is relevant for research on vector-borne diseases because Aedes spp. can transmit arboviruses such as dengue, Zika and chikungunya, and Culex spp. is a well-known vector of West Nile virus and Venezuelan equine encephalitis.

In the Caribbean region of Colombia, Lutzomyia evansi is recognized as the vector for Leishmania infantum and Leishmania braziliensis. Identifying breeding sites and surveying abundance of immature phlebotomine sand flies in urban foci of leishmaniasis are useful tool to design new vector control strategies. The objective of this study was to describe the natural breeding sites of Lu. evansi in peridomiciliary vegetation in a peri-urban area of the Colombian Caribbean region. Between 2013 and 2015, 466 microhabitats were sampled, collecting 621 kg of soil samples. The explored microhabitats were bases and tree holes, fallen trees, animal caves, leaf litter, domestic animal shelters, and the inside of dwellings. The immature phlebotomines were recovered by direct search under the stereoscope and incubation of soil samples. In total, 103 microhabitats, associated with 17 arboreal species, were identified as natural breeding sites. Of 422 immature sandflies detected, 98.6% were found in soils at the base of the trees. Eight species of the genus Lutzomyia were identified, of which Lu. evansi (52.6%) was the most abundant, followed by Lu. rangeliana, Lu. cayennensis cayennensis, Lu. atroclavata, Lu. micropyga, Lu. trinidadensis, Lu. dubitans and Lu. gomezi. The arboreal species Cordia alba was the most used by phlebotomines for the development of their immature stages. From 63 natural breeding sites identified 268 immatures were recovered including 176 Lu. evansi. The accumulated precipitation showed correlation (R2 = 0.643, p = 0.013) with the abundance of developmental stages, which increased in September and October. The natural breeding sites of Lu. evansi exhibited a local pattern of occurrence dependent on rainfall. The physicochemical analysis of the soil samples showed that the natural sites for C. alba were categorized as fertile loam soils. This is the first systematic study that estimates the temporal variation of immature sand flies in peridomiciliary vegetation in a peri-urban focus of leishmaniasis in Colombia.

The study of transmission foci involves the clinical characterization of disease within a focus using active surveillance of human cases, characterization of the population group that is most frequently infected or at highest risk of becoming infected, diagnosis and treatment of infected people and identification of the conceptions, attitudes, beliefs and practices related to the disease. An entomological survey is necessary to determine the geographical distribution of species and incrimination of vector species, the ecological characteristics of the zone (macro-focus), times of the year and day of highest biting activity and places in homes in which the most frequent contact between the people and the vectors occurs. A survey of peri-domestic and wild mammals in the area is advisable to try to identify potential reservoir hosts. Using this information, it is feasible to design specific and accurate prevention and effective, rational and economic control measures and define the times of the year and locations in which these measures must be applied. In this chapter, a description of the application of the eco-epidemiological method to the study of leishmaniasis transmission foci is provided. A special emphasis is placed on the methodology, multidisciplinary work and analysis of findings.

BACKGROUND & OBJECTIVESEcoepidemiological studies of cutaneous leishmaniasis and regular monitoring of Lutzomyia species have generated a knowledge base that can be used for control and prevention strategies targeted at the disease transmission dynamics in focal areas of Colombia. In this study, the presence and spatial distribution of phlebotomines of medical importance in the municipalities of Tierralta (El Loro and Tuis Tuis villages) and Valencia (Guadua and Mieles villages) were determined.METHODSEntomological surveys were performed in 2015 (months of June, September and November) and samples were collected via CDC-traps located in intradomicilary and peridomiciliary areas in the municipalities of Tierralta and Valencia (Department of Córdoba, Colombia). Active searches were also carried out with a mouth aspirator to collect adult phlebotomines from resting sites. ANOVA and Kruskal-Wallis tests were performed to assess if the differences between the communities of phlebotomines. Spatial distribution maps of the Lutzomyia species were generated.RESULTSA high species diversity of Lutzomyia was observed with a total of 1677 Lutzomyia individuals belonging to 12 species. Among these species, Lu. panamensis was the most abundant (80.18%). The composition of the intradomicilary and peridomiciliary phlebotomines varied significantly (F = 0.9962; df = 1; p = 0.02895). Species like Lu. carpenteri, Lu. camposi, Lu. dysponeta, Lu. atroclavata and Lu. yuilli yuilli were recorded for the first time in the Department of Córdoba, Colombia.INTERPRETATION & CONCLUSIONThe spatial distribution shows that Lu. panamensis and Lu. gomezi are predominant and present in areas with high concentration of houses. This study provides basic information on new records of phlebotomines in the Department of Córdoba. The results suggest that greater vector-human contact occurs in the peridomiciliary environment and that a high number of Lutzomyia species associated with the transmission of leishmaniasis are present in Colombia.

Background The location of the microhabitats where immature phlebotomine sand flies of the genus Lutzomyia develop is one of the least-known aspects of this group of medically important insects. For this reason strategies of source reduction approach for their control have not been possible in contrast to other insect vectors (such as mosquitoes), because their juvenile stages in terrestrial microhabitats is difficult to detect. Methods Direct examination of soil samples, incubation of substrates and the use of emergence traps were the methods used to identify juvenile stages in 160 soil samples from urban and forest habitats within the foci of Leishmania transmission in Colombia. Immatures collected were identified subsequent from the rearing and emergence of adults using taxonomic keys or the analysis of the mitochondrial marker cytochrome oxidase I. Plant species associated with the natural breeding sites were identified and physicochemical properties of the soils were analyzed. Results A total of 38 (23.7%) sampling sites were identified as breeding sites, 142 phlebotomine sand flies were identified, belonging to 13 species of the genus Lutzomyia and two of Brumptomyia . The greatest numbers of immature were found within the tabular roots (51 immature sand flies from eight positive sites) and bases of trees (35 immature sand flies from 11 sites). The characterization and presence of the tree species (mainly Ceiba pentadra, Anacardium excelsum, Pseudosamanea guachapale ) and the physicochemical properties (relative humidity and carbon/nitrogen ratio) of the soils associated with these breeding sites are significant factors in explaining the diversity and abundance of phlebotomine sand flies. Conclusions Immature phlebotomine sand flies of the genus Lutzomyia in Colombia can be found in a wide variety of breeding sites rich in organic matter, high relative humidity and are associated with a typical vegetation of each locality. These results provide new perspectives for the study of the ecology of the genus Lutzomyia in Colombia and the development of vector control strategies.

Objetivo: La leishmaniasis cutanea (LC) afecta principalmente a las poblaciones humanas mas pobres y que tienen dificultad en el acceso a los servicios de salud. El cambio climatico y las variaciones ambientales alteran la dinamica epidemiologica de la LC, haciendo mas complejo el diseno e implementacion de estrategias de control. Por lo tanto, es fundamental conocer la ecoepidemiologia de cada foco de transmision para poder adaptar mejor las medidas de control a cada situacion. El objetivo de este trabajo fue describir un foco endemico de LC en el corregimiento Puerto Valdivia, Antioquia. Metodos: Para la colecta de flebotomineos se usaron trampas CDC y Shannon y busqueda activa en sitios de reposo. Los mamiferos silvestres se capturaron mediante trampas Tomahawk®, tomando de ellos muestra de tejido para diagnostico por cultivo del parasito y metodos moleculares. Adicionalmente se tomo muestra de sangre para cultivo y deteccion de anticuerpos anti-Leishmania, a los perros llevados voluntariamente por sus duenos al centro de salud. Los casos de LC en humanos fueron evaluados mediante examen directo y aspirado de lesion para cultivo de parasitos y diagnostico molecular. Resultados: Se identificaron taxonomicamente trece especies de flebotomineos, incluyendo Lutzomyia trapidoi, Lu. gomezi, Lu. yuilli, Lu. panamensis, Lu. olmeca bicolor y Lu. hartmanni, cuya importancia medica ha sido reportada en la literatura. Se detectaron anticuerpos contra Leishmania en dos de las 32 muestras de sueros procedentes de los perros. Se capturaron dos especies de mamiferos silvestres: Didelphis marsupialis (n=3) y Proechimys semispinosus (n=1), en los cuales el diagnostico molecular y aislamiento del parasito fueron negativos. La especie de parasito circulante en pacientes se identifico como Leishmania (V.) panamensis. Conclusion: La transmision de la enfermedad en este corregimiento esta favorecida por la coexistencia de seis especies de flebotomineos altamente antropofilicas e incriminadas como vectores, particularmente para L. (V.) panamensis, especie circulante en la zona de estudio. Se sugiere implementar estudios de vigilancia entomologica para determinar el vector principal de la LC Puerto Valdivia, y poder asi recomendar las medidas mas adecuadas de prevencion y control para este foco.

Objective: cutaneous leishmaniasis (CL) affects mainly the poorest human populations with difficult access to health services. Climate change and environmental fluctuations modify the epidemiological dynamics of CL, complicating the design and implementation of control strategies. It is therefore fundamental to study the ecoepidemiology of each transmission focus in order to better adapt control measures to each situation. Our objective was to describe an endemic focus of CL in Puerto Valdivia, Antioquia. Methods: We collected sandflies with CDC and Shannon traps, and as well as through active search for resting sites. Samples were taken from wild mammals captured with Tomahawk (R) traps, and from dogs volunteered by their owners. We diagnosed human CL cases through direct examination and aspirate of the lesion. All samples obtained were processed through parasite culture and molecular methods. Results: Thirteen species of sandflies were taxonomically identified, of which Lutzomyia trapidoi, Lu. gomezi, Lu. yuilli, Lu. panamensis, Lu. olmeca bicolor and Lu. hartmanni are of medical importance according to literature. Antibodies against Leishmania were detected in two of the 32 sera samples obtained from the dogs. Two species of wild mammals were captured: Didelphis marsupialis (n=3) and Proechimys semispinosus (n=1), which were negative for both parasite isolation in culture and molecular diagnosis. The parasite species found in patients was Leishmania (V.) panamensis. Conclusion: the transmission of the disease is favored by the coexistence of six species of highly anthropophilic sandflies that have been incriminated as vectors, particularly of L. (V.) panamensis, which is present in the area of study. We suggest the implementation of entomological surveillance studies to determine the main vector of CL in Puerto Valdivia, to recommend the most appropriate prevention and control measures for this focus.

Las leishmaniasis son endémicas en >98 países con 14 millones de infectados. Leishmania sobrevive en los mamíferos aún después del tratamiento pero se desconoce su capacidad de persistir en piel sana e infectar vectores. Para demostrar la migración de Leishmania (Viannia) panamensis a piel sana, su persistencia en estos sitios durante estados crónicos de infección y la infectividad de los parásitos persistentes para Lutzomyia longipalpis, se inocularon 10 hámsters intradérmicamente en pata con 2x10(7)promastigotes de L. (V.) panamensis. Los hámsters se sacrificaron a las 13 (fase aguda) y 53 (fase crónica) semanas post-infección. Biopsias de lesión, piel sana y otros tejidos se analizaron por reacción en cadena de la polimerasa (PCR) con el gen Hsp70 y qPCR con el gen DNA polymerase. La transmisión de los parásitos a Lu. longipalpis se determinó mediante xenodiagnóstico. Todas las muestras de fase aguda (excepto oreja contralateral) y todas las muestras de fase crónica fueron positivas, aunque la positividad en fase crónica fue menor que en fase aguda. Dos animales de fase aguda y un animal de fase crónica fueron infecciosos al vector, después de alimentarse sobre la lesión. No hubo ningún insecto positivo en los alimentados sobre piel sana. Se reporta por primera vez la diseminación y persistencia de L. (V) panamensis, y se confirma la persistencia en un periodo de 53 semanas. Sin embargo la carga parasitaria en tejidos diferentes al sitio de inóculo fue baja y no se detectó su transmisión al vector. La PCR con Hsp70 y qPCR con DNA polymerase son técnicas útiles en la determinación del estatus infeccioso en los hospederos vertebrados.

Leishmaniasis are endemic in >98 countries with 14 million people infected. Leishmania survives in mammal hosts even after treatment but the capacity to persist in healthy skin and infect sandflies from these sites is poorly understood. To demonstrate migration of Leishmania (V.) panamensis into healty skin, persistence in these sites during chronic stages of infection and infectivity of persistant parasites to Lutzomyia longipalpis 10 hamsters were inoculated intradermally in the hind footpad, with 2x107 L. (V.) panamensis promastigotes. Hamsters were sacrificed at 13 (acute phase) and 53 (chronic phase) weeks post-infection. Biopsies from lesion, healty skin and othert tissues were screened by Hsp70 polymerase chain reaction (PCR) and DNA polymerase qPCR. Transmission of parasites to sandflies was determined by xenodiagnosis. Positivity was observed in all samples of acute infection group except the contralateral ear and chronic infection group, although the percentage of positivity in chronic infection was lower than that for acute infection. Two animals of the acute infection group and one from the chronic infection group were infective to sand flies after feeding over the lesion site. No infections were found in sandflies fed from healthy skin. Dissemination and persistence of L. (V.) panamensis was reported for first time and persisntace is confirmed for a period of 53 weeks. However, parasite load in tissues different from the inoculation site was lower and transmission to the sand fly vectors from these sites was not observed. Hsp70 PCR and qPCR are useful techniques for determining infection status of vertebrate hosts.

INTRODUCTION:Diverse taxonomical and molecular studies suggest that Lutzomyia longipalpis , main vector of visceral leishmaniasis in Latin America, is a complex of species widely distributed throughout the continent and adapted to different habitats.OBJECTIVE:To carry out entomological surveillance in the area of influence of the Miel I Hydroelectric Plant.MATERIALS AND METHODS:Adhesive traps were used in a transect covering an area of approximately 400 km for the capture of insects, which were then identified using the Young and Duncan taxonomical key.RESULTS:This study reports the presence of Lutzomyia longipalpis in the municipalities of Norcasia at an altitude of 392 masl, and in Marquetalia at 1,387 masl.CONCLUSIONS:We suggest that the increase in the geographical and altitudinal distribution could be related to the existence of the Lu. longipalpis species complex, or to environmental factors, such as the rise in temperature due to global climate changes, which create the establishment of Lu. longipalpis , generating a new epidemiological risk for new visceral leishmaniasis foci in the country.

Introduction. Diverse studies at a taxonomical and molecular level suggest that Lutzomyia longipalpis , main vector of visceral leishmaniasis in Latin America, is a complex of species with wide distribution throughout the continent and adaptation to different habitats. Objective. To carry out entomological surveillance in the area of influence of the Hydroelectric Plant Miel I. Materials and methods. Adhesive traps were used in a transect covering an area of approximately 400km for the capture of insects, which were then identified using the taxonomical key of Young and Duncan. Results. This study reports the presence of Lutzomyia longipalpis in the municipalities of Norcasia at an altitude of 392masl and in Marquetalia at 1387masl. Conclusions. We suggest that the increase in the geographical and altitudinal distribution could be related to the existence of the " Lutzomyia longipalpis " species complex, or to environmental factors such as the rise in temperature due to global climate change which creates the establishment of Lu. longipalpis , generating a new epidemiological risk for new visceral leishmaniasis foci in the country. doi: http://dx.doi.org/10.7705/biomedica.v33i2.762

Objective  To evaluate the environmental and ecological factors associated with Leishmania transmission and vector abundance in Chaparral, Tolima‐Colombia.