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Triatoma sordida is an endemic species to South America, currently considered the species most frequently found in the peridomestic environment in Brazil. This triatomine has a wide ecological tolerability that allows it to inhabit several ecotopes and use different food sources. Although the species is considered predominantly peridomestic, it is also capable of colonizing households and forming numerous intra-household colonies, leading to its inclusion among the priorities for triatomine control campaigns in Brazil. All Brazilian populations of T. sordida are considered as T. sordida sensu stricto by chromosomal analyses (which highlights their epidemiological importance), although molecular studies that characterize the genetic diversity of these populations are scarce, being restricted only to the region of Minas Gerais. Thus, several populations of this vector distributed in the states of Bahia, Goiás, Mato Grosso do Sul, and Minas Gerais were analyzed using mitochondrial markers (cyt b and nd1). Low nucleotide diversity, high haplotypic diversity, low genetic distance, and high FST value were observed, as well as the formation of a monophyletic clade of the Brazilian populations of T. sordida, which confirms that this species has low genetic variability, with all specimens in Brazil grouped in T. sordida sensu stricto. In addition to the genetic and evolutionary importance for the knowledge of the biology of these vectors, these results are important from an epidemiological point of view, thus being able to direct vector control programs.

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Leptolegnia chapmanii is a facultative pathogen of many species of mosquitoes, among which species of the genus Aedes, Culex and Anopheles stand out for their medical and sanitary importance. The potential of L. chapmanii as an alternative to control lies in its virulence, pathogenicity and specificity against the larval stages of mosquitoes, and because of its harmlessness to non-target species such as fish and amphibians, among others. The natural presence of L. chapmanii had been reported in Argentina, Brazil and the United States. Its presence is possible in other countries throughout the American continent. The development of protocols to produce, formulate, store and apply products based on this microorganism is one of the objectives proposed for the group of Entomopathogenic Fungi at the Centro de Estudios Parasitológicos y de Vectores, Universidad Nacional de La Plata. The efficacy of L. chapmanii as controller is affected by external factors such as temperature, pH, salinity and radiation among others. The process of transfer from the research centers to industry implies many phases. In this way, our project with L. chapmanii is in an initial phase, where we are working on a laboratory scale in proof of concept. We hope to begin soon with the efficacy, efficiency, stability and ecotoxicological safety tests, at the laboratory, semi-field and field scale.

Leptolegnia chapmanii es un microorganismo patógeno facultativo de diversas especies de mosquito, entre las que se destacan, por su importancia médica y sanitaria, especies de los géneros Aedes, Culex y Anopheles. El potencial de L. chapmanii como alternativa de control radica en la virulencia, capacidad patógena y grado de especificidad que presenta hacia los estadios larvales de las diferentes especies de mosquito, y por su inocuidad frente a organismos acuáticos no blanco como, por ejemplo, peces y anfibios. Su presencia natural ha sido reportada en Argentina, Brasil, y Estados Unidos, pensándose como posible en otros países dentro del continente americano. La eficacia de L. chapmanii como controlador se ve influenciada por factores externos, como la temperatura, la radiación y el pH, entre otros. Uno de los objetivos de trabajo del Grupo de Hongos Entomopatógenos del Centro de Estudios Parasitológicos y de Vectores de la Universidad Nacional de La Plata, corresponde al desarrollo de protocolos para la producción, formulación, almacenamiento y aplicación de productos basados en este microorganismo. Con este referente, estamos desarrollando un proyecto con L. chapmanii que se encuentra en la fase inicial, en la que se está trabajando la prueba de concepto a escala de laboratorio. Se espera continuar en el futuro con estudios de eficacia, eficiencia, estabilidad y seguridad ecotoxicológica, a diferentes escalas.

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Leptolegnia chapmanii es un microorganismo patógeno facultativo de diversas especies de mosquito, entre las que se destacan, por su importancia médica y sanitaria, especies de los géneros Aedes, Culex y Anopheles. El potencial de L. chapmanii como alternativa de control radica en la virulencia, capacidad patógena y grado de especificidad que presenta hacia los estadios larvales de las diferentes especies de mosquito, y por su inocuidad frente a organismos acuáticos no blanco como, por ejemplo, peces y anfibios. Su presencia natural ha sido reportada en Argentina, Brasil, y Estados Unidos, pensándose como posible en otros países dentro del continente americano. La eficacia de L. chapmanii como controlador se ve influenciada por factores externos, como la temperatura, la radiación y el pH, entre otros. Uno de los objetivos de trabajo del Grupo de Hongos Entomopatógenos del Centro de Estudios Parasitológicos y de Vectores de la Universidad Nacional de La Plata, corresponde al desarrollo de protocolos para la producción, formulación, almacenamiento y aplicación de productos basados en este microorganismo. Con este referente, estamos desarrollando un proyecto con L. chapmanii que se encuentra en la fase inicial, en la que se está trabajando la prueba de concepto a escala de laboratorio. Se espera continuar en el futuro con estudios de eficacia, eficiencia, estabilidad y seguridad ecotoxicológica, a diferentes escalas.

Leptolegnia chapmanii is a facultative pathogen of many species of mosquitoes, among which species of the genus Aedes, Culex and Anopheles stand out for their medical and sanitary importance. The potential of L. chapmanii as an alternative to control lies in its virulence, pathogenicity and specificity against the larval stages of mosquitoes, and because of its harmlessness to non-target species such as fish and amphibians, among others. The natural presence of L. chapmanii had been reported in Argentina, Brazil and the United States. Its presence is possible in other countries throughout the American continent. The development of protocols to produce, formulate, store and apply products based on this microorganism is one of the objectives proposed for the group of Entomopathogenic Fungi at the Centro de Estudios Parasitológicos y de Vectores, Universidad Nacional de La Plata. The efficacy of L. chapmanii as controller is affected by external factors such as temperature, pH, salinity and radiation among others. The process of transfer from the research centers to industry implies many phases. In this way, our project with L. chapmanii is in an initial phase, where we are working on a laboratory scale in proof of concept. We hope to begin soon with the efficacy, efficiency, stability and ecotoxicological safety tests, at the laboratory, semi-field and field scale.

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INTRODUCTION: Natural populations of Anopheles darlingi, the main malaria vector in Colombia, have shown phenotypic variations in some of their diagnostic characters. OBJECTIVE: To characterize morphometric variations in wing spot patterns and diagnostic characters of the hind leg of adult females of An. darlingi collected in areas where malaria is endemic. MATERIALS AND METHODS: Patterns of the costal vein spots of wild females of An. darling populations collected in the departments of Chocó, Guaviare, Meta and Vichada were analyzed using linear and morphometric approaches. The second tarsomere of the hind leg of females was characterized by linear morphometric analysis. RESULTS: We found 19 patterns of spots in the costal vein; patterns I (n=118/240, 49%) and VI (n=66, 28%) were the most frequent. The proportion of the basal dark area of hind tarsomere II and the length of hind tarsomere II (DSIII2/Ta-III2) constituted a robust diagnostic character as it represented 89% (n=213/240) of the total specimens studied. Significant differences were found in the wing shape (F=1.65, df =50, p<0.001) and the wing size (F=3.37, df=5, p=0.005) among populations from different locations. The smallest centroid size (2.64 mm) was found in populations from Chocó. CONCLUSIONS: We registered 11 new wing spot patterns in the costal vein and the dominance of the patterns I and VI for populations of An. darlingi from Colombia. We confirmed DSIII2/TaIII2 ratio as a robust diagnostic character for the taxonomy of this species. We found differences between the size and shape of the wings of An. darlingi populations in accordance to their geographical distribution, which constitute important bionomic aspects for this malaria vector.

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BACKGROUND: The Zika virus disease (ZVD) has had a huge impact on public health in Colombia for the numbers of people affected and the presentation of Guillain-Barre syndrome (GBS) and microcephaly cases associated to ZVD. METHODS: A retrospective descriptive study was carried out, we analyze the epidemiological situation of ZVD and its association with microcephaly and GBS during a 21-month period, from October 2015 to June 2017. The variables studied were: (i) ZVD cases, (ii) ZVD cases in pregnant women, (iii) laboratory-confirmed ZVD in pregnant women, (iv) ZVD cases associated with microcephaly, (v) laboratory-confirmed ZVD associated with microcephaly, and (vi) ZVD associated to GBS cases. Average number of cases, attack rates (AR) and proportions were also calculated. The studied variables were plotted by epidemiological weeks and months. The distribution of ZVD cases in Colombia was mapped across the time using Kernel density estimator and QGIS software; we adopted Kernel Ridge Regression (KRR) and the Gaussian Kernel to estimate the number of Guillain Barre cases given the number of ZVD cases. RESULTS: One hundred eight thousand eighty-seven ZVD cases had been reported in Colombia, including 19,963 (18.5%) in pregnant women, 710 (0.66%) associated with microcephaly (AR, 4.87 cases per 10,000 live births) and 453 (0.42%) ZVD associated to GBS cases (AR, 41.9 GBS cases per 10,000 ZVD cases). It appears the cases of GBS increased in parallel with the cases of ZVD, cases of microcephaly appeared 5 months after recognition of the outbreak. The kernel density map shows that throughout the study period, the states most affected by the Zika outbreak in Colombia were mainly San Andrés and Providencia islands, Casanare, Norte de Santander, Arauca and Huila. The KRR shows that there is no proportional relationship between the number of GBS and ZVD cases. During the cross validation, the RMSE achieved for the second order polynomial kernel, the linear kernel, the sigmoid kernel, and the Gaussian kernel are 9.15, 9.2, 10.7, and 7.2 respectively. CONCLUSIONS: This study updates the epidemiological analysis of the ZVD situation in Colombia describes the geographical distribution of ZVD and shows the functional relationship between ZVD cases and GBS.

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Resumen Introducción. Las enfermedades transmitidas por vectores representan más de 17 % de todas las enfermedades infecciosas y causan anualmente un millón de defunciones a nivel mundial. En Colombia, la malaria, el dengue, la enfermedad de Chagas y las leishmaniasis son condiciones endemoepidémicas persistentes. Objetivo. Determinar el comportamiento epidemiológico de las enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016. Materiales y métodos. Se hizo un estudio descriptivo del comportamiento epidemiológico de las principales enfermedades transmitidas por vectores en zonas urbanas y rurales de Colombia entre 1990 y 2016, con la información proveniente de fuentes oficiales secundarias. Resultados. En el periodo estudiado se registraron 5'360.134 casos de enfermedades transmitidas por vectores, de los cuales 54,7 % fueron de malaria y 24,9 % de dengue. Estos casos concentraron el 80 % de la carga acumulada de casos de enfermedades transmitidas por vectores. Las medianas de las tasas de incidencia fueron 1.371 y 188 por 100.00 habitantes para malaria y dengue, respectivamente. Además, los casos de chikungunya fueron 774.831 desde su introducción en el 2014 y, los de Zika, 117.674 desde su aparición en 2015. En las zonas rurales predominaron las enfermedades parasitarias transmitidas por vectores como la malaria, las leishmaniasis y la enfermedad de Chagas. A nivel urbano, predominaron el dengue, el chikungunya y el Zika. Conclusiones. La transmisión en Colombia de estas enfermedades es persistente en las zonas urbanas y en las rurales, y de tipo endemoepidémico en los casos de malaria, dengue, leishmaniasis y enfermedad de Chagas. Dicha transmisión se ha dado de manera focalizada y con patrones variables de intensidad. Asimismo, se mantienen las condiciones que han favorecido la transmisión emergente de nuevas arbovirosis.

Abstract Introduction: Vector-borne diseases account for more than 17% of all infectious diseases and annually they cause one million deaths worldwide. In Colombia, malaria, dengue, Chagas disease, and leishmaniasis are persistent endemo-epidemic events. Objective: To determine the behavior and transmission scenarios of vector-borne diseases in Colombia between 1990 and 2016. Materials and methods: We conducted a descriptive study on the epidemiological behavior of the main vector-borne diseases in Colombia between 1990 and 2016 based on information from official secondary sources. Results: During the study period, there were 5,360,144 cases of vector-borne diseases, 54.7% of which were due to malaria and 24.9% to dengue, accounting for 80% of the cumulative disease burden of vector-borne disease cases. The median incidence rates were 1,371 and 188 per 100,000 inhabitants for malaria and dengue, respectively. In addition, emerging events such as Chikungunya registered 774,831 cases since its introduction in 2014, while 117,674 Zika fever cases were reported since its emergence in 2015. In rural settings, parasitic vector-borne diseases such as malaria, leishmaniasis and Chagas disease predominated, while in urban scenarios dengue, chikungunya and Zika were predominant. Conclusions: Persistent epidemic and endemic transmission of vector-borne diseases in urban and rural settings in Colombia was observed mainly in the case of malaria, dengue, leishmaniasis and Chagas disease. Such transmission was focused and had variable intensity patterns. On the other hand, the conditions that have favored the emergence of new arboviruses persist.

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Resumen Introducción. Las poblaciones naturales de Anopheles darlingi, principal transmisor de la malaria en Colombia, han mostrado plasticidad fenotípica en algunos de sus caracteres diagnósticos. Objetivo. Caracterizar las variaciones morfométricas de los patrones alares y de la pata posterior en poblaciones naturales de An. darlingi recolectados en localidades colombianas donde la malaria es endémica. Materiales y métodos. Se analizaron los patrones de manchas de la vena costal del ala de hembras silvestres recolectadas en los departamentos de Chocó, Guaviare, Meta y Vichada mediante morfometría lineal y geométrica. El segundo tarsómero posterior de las hembras se analizó mediante morfometría lineal. Resultados. Se encontraron 19 patrones de manchas de la vena costal. Los patrones I, con 49 % (n=118/240) y VI, con 28 % (n=66), fueron los más frecuentes. La proporción del área oscura basal (DS-III2 ) y del tarsómero posterior (Ta-III2 ) constituyó una característica sólida de diagnóstico, pues representó el 89 % (n=213/240) del total de especímenes analizados. Se encontraron diferencias significativas en la forma (F=1,65; gl=50; p<0,001) y el tamaño (F=3,37; gl=5; p=0,005) del ala entre las poblaciones de diferentes localidades. El centroide de menor tamaño (2,64 mm) se encontró en las poblaciones de Chocó. Conclusiones. Se registraron 11 patrones nuevos para las manchas de la vena costal y se confirmó la dominancia de los patrones alares I y VI en las poblaciones de An. darlingi de Colombia, así como la relación de DS-III2 y Ta-III2 como un rasgo sólido de diagnóstico para la taxonomía de la especie. Se encontraron diferencias en el tamaño corporal de las poblaciones evaluadas, lo cual reviste importancia para el análisis de aspectos bionómicos de la especie.

Abstract Introduction: Natural populations of Anopheles darlingi, the main malaria vector in Colombia, have shown phenotypic variations in some of their diagnostic characters. Objective: To characterize morphometric variations in wing spot patterns and diagnostic characters of the hind leg of adult females of An. darlingi collected in areas where malaria is endemic. Materials and methods: Patterns of the costal vein spots of wild females of An. darling populations collected in the departments of Chocó, Guaviare, Meta and Vichada were analyzed using linear and morphometric approaches. The second tarsomere of the hind leg of females was characterized by linear morphometric analysis. Results: We found 19 patterns of spots in the costal vein; patterns I (n=118/240, 49%) and VI (n=66, 28%) were the most frequent. The proportion of the basal dark area of hind tarsomere II and the length of hind tarsomere II (DSIII2 /Ta-III2) constituted a robust diagnostic character as it represented 89% (n=213/240) of the total specimens studied. Significant differences were found in the wing shape (F=1.65, df =50, p<0.001) and the wing size (F=3.37, df=5, p=0.005) among populations from different locations. The smallest centroid size (2.64 mm) was found in populations from Chocó. Conclusions. We registered 11 new wing spot patterns in the costal vein and the dominance of the patterns I and VI for populations of An. darlingi from Colombia. We confirmed DSIII2/TaIII2 ratio as a robust diagnostic character for the taxonomy of this species. We found differences between the size and shape of the wings of An. darlingi populations in accordance to their geographical distribution, which constitute important bionomic aspects for this malaria vector.

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