The 2030 Agenda for Sustainable Development is a plan of action for people, planet and prosperity. Thousands of years and centuries of colonisation have passed the precarious housing conditions, food insecurity, lack of sanitation, the limitation of surveillance, health care programs and climate change. Chagas disease continues to be a public health problem. The control programs have been successful in many countries in reducing transmission by T. cruzi; but the results have been variable. WHO makes recommendations for prevention and control with the aim of eliminating Chagas disease as a public health problem. Climate change, deforestation, migration, urbanisation, sylvatic vectors and oral transmission require integrating the economic, social, and environmental dimensions of sustainable development, as well as the links within and between objectives and sectors. While the environment scenarios change around the world, native vector species pose a significant public health threat. The man-made atmosphere change is related to the increase of triatomines’ dispersal range, or an increase of the mobility of the vectors from their sylvatic environment to man-made constructions, or humans getting into sylvatic scenarios, leading to an increase of Chagas disease infection. Innovations with the communities and collaborations among municipalities, International cooperation agencies, local governmental agencies, academic partners, developmental agencies, or environmental institutions may present promising solutions, but sustained partnerships, long-term commitment, and strong regional leadership are required. A new world has just opened up for the renewal of surveillance practices, but the lessons learned in the past should be the basis for solutions in the future.

The multiplicity of epidemiological scenarios shown by Chagas Disease, derived from multiple transmission routes of the aetiological agent, occurring on multiple geo-ecobiosocial settings determines the complexity of the disease and reveal the difficulties for its control. From the first description of the link between the parasite, the vector and its domestic habitat and the disease that Carlos Chagas made in 1909, the epidemiological scenarios of the American Trypanosomiasis has shown a dynamic increasing complexity. These scenarios changed with time and geography because of new understandings of the disease from multiple studies, because of policies change at the national and international levels and because human movements brought the parasite and vectors to new geographies. Paradigms that seemed solid at a time were broken down, and we learnt about the global dispersion of Trypanosoma cruzi infection, the multiplicity of transmission routes, that the infection can be cured, and that triatomines are not only a health threat in Latin America. We consider the multiple epidemiological scenarios through the different T. cruzi transmission routes, with or without the participation of a Triatominae vector. We then consider the scenario of regions with vectors without the parasite, to finish with the consideration of future prospects.

Abstract Vector-borne diseases (VBDs) continue to pose a challenge to the efforts of public health agencies by increasing their impact on the health of the affected communities. The common feature of VBDs is that the only way of preventing them is by avoid ing the contact between vectors and humans. There are no vaccines, and they will not be available shortly as tools for prevention and control in Argentina. Although dengue outbreaks attracted the attention of mass media from 2009, other VBDs have been affecting public health in Argentina for many decades, as Chagas disease and leishmaniasis. Over these, and others that could potentially settle in the national territory (West Nile, Lyme, etc.), there are repeated mass media claims and political declarations justifying their increase because of climate changes. The argument asserts that the “tropicalization” of the climate in temperate regions promotes the instal lation of VBDs in areas previously unfavorable for them. Although much evidence exists showing that the climate is changing, there is very little evidence that the climate is the main factor promoting the increase of VBDs. In this article, the influence of the so-called climate change on the situation of disease vectors in Argentina (with emphasis on triatomines) and vector control activities implemented by governmental public health agencies are discussed.

Resumen Las enfermedades transmitidas por vectores (ETVs) continúan siendo un desafío para los esfuerzos de agencias de salud pública, ya que mantienen o están aumentando su impacto sobre la salud de las comunidades afectadas. La característica común de las ETVs es que la única manera de prevenir exito samente nuevas infecciones es evitar el contacto entre vectores y humanos. No existen vacunas y no existirán en un futuro previsible para las principales ETVs que afectan la salud pública en Argentina. Aunque las epide mias de dengue desde 2009 atrajeron la atención mediática, otras ETVs, tales como Chagas o leishmaniasis, afectan la salud pública en Argentina desde hace décadas. Sobre ellas, y otras que potencialmente podrían instalarse en el territorio nacional (West Nile, Lyme, etc) hay repetidas referencias mediáticas que explican su recrudecimiento por el cambio climático. El argumento se basa en que la “tropicalización” del clima en regiones templadas promueve la instalación de ETVs en áreas previamente no favorables para ellas. Aunque existen muchas evidencias de que el clima está cambiando, son pocas las evidencias de que sea el clima el principal factor que promueve el recrudecimiento de las ETVs en Argentina. En este artículo, se discute la situación de los vectores de enfermedades en Argentina (con énfasis en triatominos), su vinculación con el llamado cambio climático y las actividades de control de vectores implementados por agencias gubernamentales de salud pública.

This is a description of experimental field studies that evaluated the efficacy of Telenomus fariai as a biological control agent of Triatoma infestans, the main vector of Trypanosoma cruzi (the aetiological agent of Chagas disease) in the Southern Cone countries of Latin America. The objective of this note is to report the inefficacy of T fariai to regulate the population abundance of T infestans under field conditions in a narrative way, as the original data have long been lost and unpublished because "negative” results were not published at the time (1980s). The aim is to correct that selective reporting and inform interested colleagues about efforts made on an idea that was (and probably still is) very appealing at the time the work was made.

Esta es una descripción de estudios experimentales hechos en campo para evaluar la eficacia de Telenomus fariai como agente de control biológico de Triatoma infestans, el principal vector de Trypanosoma cruzi (agente etiológico de la enfermedad de Chagas) en países del Cono Sur de Sud América. El objetivo de esta nota es informar la ineficacia de T fariai para regular la abundancia poblacional de T infestans bajo condiciones de campo en forma narrativa, ya que desafortunadamente los datos originales se perdieron hace tiempo, no publicados debido a que los resultados "negativos” no eran usualmente publicados al momento de los estudios (década de 1980). La finalidad de la nota es corregir el reporte selectivo e informar a colegas interesados acerca de los esfuerzos hechos sobre una idea que era (y probablemente aún es) muy atractiva al momento de realizar el trabajo.

Triatoma infestans is the main vector of the parasite that causes the Chagas disease in South America. It is known that T. infestans has different reproductive and development patterns depending on whether they feed on birds or mammals. Using the head of adult insects as an estimator of the specimen development, we attempt to determine if there are any differences in the sexual size dimorphism associated with the availability of the food resource in T. infestansof natural habitats in the Llanos Riojanos region (Argentina). The nutritional status resulted higher in chicken coops and, in both habitats, it was higher for females in relation to males. The centroid size was larger in females than in males from chicken coops, but not in the specimens from goat corrals. Centroid sizes revealed smaller medians in goat insects in comparison to those coming from chicken coops. Sexual size dimorphism occurs associated with differences in the nutritional status only for triatomines from chicken coops in natural habitats. The heads shape was not infuenced by the nutritional status. The sexual morphophysiological differences found in T. infestanshelp us understand aspects of the behavior of the species in diverse environments and its implications in the vectorial transmission o f Trypanosoma cruzi.

Triatoma infestanses el principal vector del parásito que causa la enfermedad de Chagas en Sudamérica. Se sabe que T. infestanstiene diferentes patrones reproductivos y de desarrollo dependiendo de si se alimentan de aves o mamíferos. Utilizando la cabeza de insectos adultos como estimador del desarrollo, se intenta determinar si existen diferencias en el dimorfsmo de tamaño sexual asociado con la disponibilidad del recurso alimenticio e n T. infestans de hábitats naturales en la región de Llanos Riojanos (Argentina). El estado nutricional fue mayor en gallineros y, en ambos hábitats, fue mayor para las hembras en relación con los machos. El tamaño centroide fue mayor en las hembras que en los machos de gallineros, pero no en los especímenes de corrales de cabras. Los tamaños centroide revelaron medianas más pequeñas en insectos de cabra en comparación con los procedentes de gallineros. El dimorfsmo sexual del tamaño se asocia con diferencias en el estado nutricional solo para triatominos de gallineros de habitats naturales. La conformación de las cabezas no se vio infuenciada por el estado nutricional. Las diferencias morfofsiológicas encontradas en T. infestans ayudan a comprender aspectos del comportamiento de la especie en diversos ambientes y sus implicaciones en la transmisión vectorial d eTrypanosoma cruzi.

Urban centers are dominated by species adapted to human presence. The intensity of human activity has a strong influence on habitat selection by animal populations across landscapes. The objectives of this study were to assess the abundance and the spatial distribution of the nests of two species of pigeons (Columba livia and Patagioenas maculosa), and evaluate the effects of human factors on the probability of nesting-site selection in different urban zones within a desert city. Nest abundance increased for Columba livia in city centers and for Patagioenas maculosa in zones away from them, in green areas. The most important variables influencing the probability of nesting-site selection by Columba livia were distance to the main square, distance to food sources and the interaction between distance to food sources and distance to water, along with type and height of buildings. For Patagioenas maculosa, the variables influencing the probability of nestingsite selection were distance to water, human population density, distance to food sources and the interaction between human population density and distance to food sources, along with tree height and diameter of tree canopy. This species selected Platanus×hispanica and Morus spp. as nesting sites. Nesting sites could be a limiting factor for these species, and our results have important implications for choosing appropriate control strategies for the management of urban pigeons in desert environments.

Los centros urbanos están dominados por especies adaptadas a la presencia humana. La intensidad de la actividad humana tiene una fuerte influencia sobre la selección del hábitat en poblaciones animales. Los objetivos de este estudio fueron estimar la abundancia y la distribución espacial de los nidos de dos especies de palomas (Columba livia and Patagioenas maculosa) y evaluar los efectos de factores humanos sobre la probabilidad de selección de sitios de nidificación en diferentes zonas en una ciudad de desierto. La abundancia de nidos de Columba livia aumentó en el centro de la ciudad y para Patagioenas maculosa en zonas alejadas del centro, en áreas verdes. Las variables más influyentes en la probabilidad de selección de sitios de nidificación para Columba livia fueron distancia a la plaza principal, distancia a las fuentes de alimento y la interacción entre la distancia a las fuentes de alimento y la distancia al agua, además del tipo y la altura de los edificios. Para Patagioenas maculosa las variables más influyentes en la probabilidad de selección de sitios de nidificación fueron la distancia al agua, la densidad poblacional humana, la distancia a las fuentes de alimento y la interacción entre la densidad poblacional humana y la distancia a las fuentes de alimento, además de la altura del árbol y el diámetro de la copa. Además, esta especie seleccionó Platanus×hispanica y Morus spp. como sitio de nidificación. Los sitios de reproducción podrían ser un factor limitante para estas especies; los resultados de este estudio tienen importantes implicancias para la elección de estrategias apropiadas de control en el manejo de palomas de ambientes urbanos en zonas desérticas.

Triatoma infestans is the most important vector of Chagas disease in Argentina. We report for the first time the presence of T. infestans (Klug) (Hemiptera: Reduviidae) associated with burrowing parrot nests Cyanoliseus patagonus (Psittasiformes: Psittacidae) built on abandoned adobe houses. The possible implications of this finding are discussed, for entomological surveillance of the vector.

Triatoma infestans es el vector más importante de la enfermedad de Chagas de la Argentina. Se cita por primera vez la presencia de T. infestans (Klug) (Hemiptera: Reduviidae) asociado a nidos de loro barranquero Cyanoliseus patagonus (Psittasiformes: Psittacidae) construidos en viviendas de adobe abandonadas. Se discuten las posibles implicancias de este hallazgo para la vigilancia entomológica del vector.

This article reports the effects of a pour-on formulation of cypermethrin (6% active ingredient) applied to chickens exposed to Triatoma infestans, the main vector of Chagas disease in rural houses of the Gran Chaco Region of South America. This study was designed as a completely random experiment with three experimental groups and five replicates. Third instar nymphs were fed on chickens treated with 0, 1 and 2 cc of the formulation. Nymphs were allowed to feed on the chickens at different time intervals after the insecticide application. Third-instar nymphs fed on treated chickens showed a higher mortality, took less blood during feeding and had a lower moulting rate. The mortality rate was highest seven days after the insecticide solution application and blood intake was affected until 30 days after the application of the solution.

The paper presents an analysis of the geographic distribution of Triatoma infestans based on biophysical variables recorded by meteorological satellites. The analysis includes data derived from a temporal Fourier Analysis of monthly images over a set of 14 derived statistical descriptors of the average, minimum, maximum, variability, amplitude and phase of the air temperature, land surface temperature, medium infrared radiation and a vegetation index remotely sensed by the AVHRR. Temporal series covered the period 1982-2000, and the area from Panamá to Tierra del Fuego. The analysis of individual variables showed that the annual phase of the normalised difference vegetation index identifies correctly 80% presence and absence sites of Triatoma infestans. The analysis confirms the importance of temperature (especially air temperature) for Triatoma infestans distribution, as 7 (out of 14) statistical descriptors associated with air temperature identified correctly >70% of presence and absence sites. A Stepwise Linear Discriminant Analysis showed that a function with six statistical descriptors (four of them associated with air temperature, one associated with medium infrared radiation, and one with the vegetation index) identified correctly 90% of presence and absence sites of Triatoma infestans. The analysis shows the important association between the environmental variables studied at the continental scale and the distribution of a strictly domestic and haematophagous species. The approach could be useful for large scale studies of the distribution of other species with more direct and causal relation with vegetation and climate than Triatoma infestans.

El trabajo presenta un análisis de la distribución geográfica de Triatoma infestans basado en variables biofísicas calculadas a partir de datos obtenidos por satélites meteorológicos. Se consideran datos derivados de un Análisis Temporal de Fourier sobre imágenes mensuales que contienen un conjunto de 14 descriptores estadísticos del promedio, mínimo, máximo, variabilidad, amplitud y fase de la temperatura del aire, la temperatura de superficie, la radiación infrarroja media y el índice de vegetación calculados con datos colectados por el sensor AVHRR. La serie temporal considerada cubre el período 1982-2000 y el área abarca desde Panamá hasta Tierra del Fuego. El análisis de variables individuales mostró que la fase anual del índice de vegetación identifica correctamente el 80% de los sitios donde Triatoma infestans está presente y ausente. El análisis confirmó la importancia de la temperatura (especialmente la del aire) sobre la distribución de Triatoma infestans, ya que 7 descriptores estadísticos de la temperatura del aire (de un total de 14) identificaron correctamente >70% de los sitios donde Triatoma infestans está ausente y presente. Un Análisis Lineal Discriminante por Pasos mostró que una función con seis descriptores estadísticos (cuatro asociados con la temperatura del aire, uno con la radiación infrarroja media y uno con el índice de vegetación) identificaron correctamente el 90% de los sitios donde Triatoma infestans está presente y ausente. El análisis muestra la importante asociación entre las variables estudiadas a escala continental y la distribución de una especie doméstica y hematófaga. El enfoque de trabajo puede resultar de utilidad en estudios de escala geográfica amplia sobre la distribución de otras especies con una relación más directa y causal con la vegetación y el clima que Triatoma infestans.

Delphacodes kuscheli is the vector of the Río Cuarto Corn Disease, which affects maize in central Argentina. This disease is endemic of Rio Cuarto Department in Córdoba Province. Preliminary studies indicate that the insect is present in Córdoba, La Pampa, San Luis, Santa Fe and Buenos Aires provinces, but there are few studies on the abundance in these places. Previous research showed that Delphacodes kuscheli arrives to maize plots from distant sources, and that there is a difference in the abundance of Delphacodes kuscheli in the endemic area and outside it. In this work we study the geographic variations of the population abundance of Delphacodes kuscheli along a transect that crosses the endemic area to verify whether there is a difference between the vector population dynamics within and outside the endemic area. Samples of dispersing individual were collected during three years by using sticky traps at two different heights. The samples were taken in eight sampling sites between the localities of Manfredi (Córdoba) and Mercedes (San Luis). Dispersive individuals of Delphacodes kuscheli were more abundant in the endemic area than outside it. The dispersive population captured with low traps had a higher proportion of females, but there were no differences at high traps. The correlation of density changes observed in high traps decreased with distance between sampling sites, but there was no relationship for low traps. It is discussed how these results could indicate that Delphacodes kuscheli is a species highly adapted to live in unstable habitats.

Delphacodes kuscheli es uno de los vectores del virus causante del Mal de Río Cuarto del Maíz en el área central de Argentina. Esta enfermedad es endémica del departamento de Río Cuarto en la Provincia de Córdoba. Si bien estudios previos sitúan al insecto en Córdoba, La Pampa, San Luis, Santa Fe y Buenos Aires, existen pocos estudios sobre su dinámica poblacional en un área extendida. En este trabajo se estudian las variaciones estacionales de la abundancia de poblaciones de individuos dispersivos de Delphacodes kuscheli a lo largo de una transecta con origen fuera del área endémica y que pasa por ésta. Se realizaron muestreos de individuos dispersivos a dos niveles de altura mediante trampas pegajosas durante tres años. Las muestras fueron tomadas en ocho sitios entre Manfredi (Córdoba) y Mercedes (San Luis). Los individuos dispersivos fueron más abundantes en el área endémica que fuera de ella. La proporción de hembras capturadas fue mayor que la de machos en las trampas bajas, mientras que no fue diferente en las trampas altas. Existió una correlación negativa entre los cambios temporales de densidad y la distancia de separación entre sitios de muestreo en el caso de las trampas altas, pero no para las trampas bajas. Se discute la relación entre los resultados observados y la adaptación a ambientes inestables por parte de Delphacodes kuscheli.

The larvae of Lepidoptera are very important crop pests in central Córdoba Province (Argentina), because of the yield losses they produce on corn and soybean. We compared the efficiency of two light traps, one with a 125 W mercury vapour lamp HPL type and other with a 15-W blacklight lamp. Moth catches were counted 1-3 times/week, from December 1997 to December 2000. The comparison of trap efficiency for each species was carried out with the slope of the relationship between week catches obtained for each trap. The mercury vapour trap was more efficient for most of the species, with some variations depending on the period that was analysed. There were no significant differences between traps for Agrotis malefida and Agrotis ipsilon, and the blacklight trap was more efficient for Helicoverpa zea, Spodoptera frugiperda and Spilosoma virginica. For 8 out of the 18 collected species the efficiency of the traps depended on the species density.

En el centro de la provincia de Córdoba las larvas de Lepidoptera constituyen plagas de gran importancia debido a las pérdidas de rendimiento que ocasionan en los cultivos de maíz y soja. En este trabajo se compara la eficiencia de captura de adultos de Lepidoptera en dos trampas de luz, una con lámpara de vapor de mercurio tipo HPL de 125 W y otra con un tubo de luz negra de 15 W. La recolección de adultos se realizó con una frecuencia de 1-3 veces por semana, desde diciembre 1997 hasta diciembre 2000. La comparación de la eficiencia de las trampas para cada especie se realizó estimando la pendiente de la relación entre las capturas semanales obtenidas por cada tipo de trampa. En general, se observó mayor eficiencia de captura en las trampas de luz de vapor de mercurio, con algunas variaciones de acuerdo al período analizado. No se observaron diferencias significativas entre ambas trampas para Agrotis malefida y Agrotis ipsilon, y la trampa de luz negra fue más eficiente solo para Helicoverpa zea, Spodoptera frugiperda y Spilosoma virginica. La eficiencia de las trampas resultó densodependiente en 8 de las 18 especies capturadas.

Aedes albifasciatus is an important common mosquito in Central Argentina. Its a confirmed vector of the Western Equine Encephalitis and is responsible for loss of milk production in dairy cattle during peak populations. This paper reports the flight activity pattern of Ae. albifasciatus for different seasons, in the southern coast of the Mar Chiquita Lake (Central Argentina). Data were collected by sampling two sites between 1992 and 1993 with CDC traps and human-bait captures. Adult mosquito population density, estimated by CDC trapping and human-bait, were highly correlated. However, when compared to other species, the proportion of Ae. albifasciatus was higher in human-bait collections. Adult female populations were active only when temperature were higher than 6§C. Two daily biting peaks were observed (dusk and dawn) during the spring, summer and autumn, and only one peak during winter (around 15:00 pm). Adult abundance was significantly correlated (R²= 0.71; p<0.01) with temperature and illumination.

Aedes albifasciatus is a flood water mosquito ocurring in the southern countries of South America. It is a competent vector of the Western Equine Encephalitis (WEE) and causes important losses on milk and beef production in central Argentina. Field work was carried out from December 1990 to March 1993, on a monthly basis during the dry season and biweekly during the rainy season. Larvae were collected using the 'dipping' technique and females with CDC traps baited with CO2. Field collected larvae were used to build laboratory cohorts, from which basic population parameters were estimated. Eggs survived up to six months on dry soil, although there was a linear decrease of viability with time. At 23ºC, larval development time was around nine days, and all adults emerged within one week. The estimation of larval development in the laboratory seems to be very near the development on the field, as larvae have been collected on average eight days after a rainfall. Egg to adult survival was 83%, with the highest mortality on fourth larval instar (6%). In the laboratory studies, sex proportion among the adults was 1:1, females lived longer than males (median 13 and five days, respectively), and adult survival pattern showed a constant number of individuals dying per unit time. Field collected females layed an average of 84 eggs per batch, and completing up to five gonotrophic cycles, suggesting an estimated survival of up to 35-50 days.

Because of the relative epidemiological significance of Triatoma sordida, T. guasayana and T. patagonica, and the need to resolve doubts about their taxonomic validity, we report here a detailed taxonomic comparison of the three species using multivariate analysis of morphometric measures combined with comparisons of their genitalia and antennal structures. From the 17 metric variables studied, the length of the second segment of the rostrum and the anteocular length provided a discrimination function able to separate without error T. sordida from T. guasayana and T. patagonica. The multivariate discriminant functions classified T. guasayana and T. patagonica with an error of 2.44%. Comparison of the male genitalia of T. guasayana and T. sordida showed that there are minor differences in the articulatory apparatus, the median process of the pygophore, the phallosome support and the vesica, with bigger differences in the endosomal process and the phallosome. However, the already described male genitalia of T. patagonica is very similar to that of T. sordida. Analysis of antennal structure by scanning electron microscope showed that sensilla distribution around the pedicel is slightly different in the three species and sensilla density is highest in T. sordida and lowest in T. patagonica. The study showed that the three species form a closely related group. The results confirm the earlier classification of sordida and guasayana as separate species, but they raise some doubts about the taxonomic status of T. patagonica.