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Additional file 2: Supplementary Figure 1. Negative controls performed during sample processing did not generate any amplicons during the quality control carried out by the sequencing facility.

Additional file 8: Supplementary Table 1. Bacteria genera isolated from Aedes aegypti exposed to bacteria of the genera Asaia or Elizabethkingia and the control group.

Additional file 7: Supplementary Figure 1. Duration of all larval instars and pupal phase of Aedes aegypti exposed to bacteria of the genera Asaia or Elizabethkingia and the control group. The dashed lines in the graphs indicate median developmental time. Hazard ratios and 95% confidence intervals associated with Asaia or Elizabethkingia exposure were estimated using Cox Proportional-Hazard models with developmental time as the dependent variable. Black squares represent the hazard ratios and the horizontal bars extend from the lower limit to the upper limit of the 95% confidence intervals of the hazard ratios.

Additional file 1: Supplementary Table 1. Number of eggs laid by each Aedes aegypti female in treatment 5.

Additional file 3: Supplementary Table 1. Bacterial taxonomic affiliation of isolates recovered from LB agar plates. Supplementary Table 2. Bacterial taxonomic affiliation of isolates recovered from blood agar plates.

Additional file 5: Supplementary Figure 1. Bacterial community composition at order level for each water sample belonging to five different treatments.

Additional file 6: Supplementary Figure 1. Heatmap of the Jensen-Shannon distances between the five treatments.

Additional file 4: Supplementary Table 1. Dunn test comparing alpha diversity between treatments. P values adjusted with the Benjamini-Hochberg method are shown. Supplementary Table 2. Pairwise PERMANOVA showing between-group shifts in bacterial signature profile when comparing the beta diversity among treatments. P values for each comparison are shown. Supplementary Figure 1. ROC curves for female interaction and eggs presence prediction. The point indicates the best cutoff value from the prediction probability to optimize Sensitivity and Specificity. The confidence levels reflect a 95% confidence interval. Supplementary Table 3. Median, mean and standard deviation of instar duration of immature stages of Aedes aegypti, wing size, and survival exposed to Asaia and Elizabethkingia bacteria.

Pathogens may manipulate their human and mosquito hosts to enhance disease transmission. Dengue, caused by four viral serotypes, is the fastest-growing transmissible disease globally resulting in 50–100 million infections annually. Transmission of the disease relies on the interaction between humans and the vector Aedes aegypti and is largely dependent on the odor-mediated host seeking of female mosquitoes. In this study, we use activity monitors to demonstrate that dengue virus-1 affects the locomotion and odor-mediated behavior of Ae. aegypti, reflecting the progression of infection within the mosquito. Mosquitoes 4–6 days post-infection increase locomotion, but do not alter their odor-driven host-seeking response. In contrast, females 14–16 days post-infection are less active, yet more sensitive to human odors as assessed by behavioral and electrophysiological assays. Such an increase in physiological and behavioral sensitivity is reflected by the antennal-specific increase in abundance of neural signaling transcripts in 14 days post-infection females, as determined by transcriptome analysis. This suggests that the sensitivity of the mosquito peripheral olfactory system is altered by the dengue virus by enhancing the overall neural responsiveness of the antenna, rather than the selective regulation of chemosensory-related genes. Our study reveals that dengue virus-1 enhances vector-related behaviors in the early stages post-infection that aid in avoiding predation and increasing spatial exploration. On the other hand, at the later stages of infection, the virus enhances the host-seeking capacity of the vector, thereby increasing the risk of virus transmission. A potential mechanism is discussed., Author summary The mosquito Aedes aegypti is a major urban vector for human pathogens, including dengue, the most rapidly-spreading infectious disease globally. We show that one of the four strains of the dengue virus differentially, and inversely, affects the locomotion and odour-mediated behaviour of female Aedes aegypti. During the early stages after infection, female mosquitoes show an increased locomotion activity suggesting that the virus likely promotes mosquito dispersion and increases its spatial exploration. In contrast, in the later infective stages, dengue infection modulates the mosquito’s host-seeking capacity, by enhancing the physiological and behavioural sensitivity to human odors, thus increasing the risk of virus transmission. At this stage of infection, neural signalling gene expression is enhanced, providing a mechanism for the increased sensitivity to human odor, while genes involved in chemosensation and neuromodulation are likely playing a secondary role. A better understanding of alterations of mosquito host-seeking behavior upon pathogen infection will contribute to the development of novel control strategies against vector borne diseases.

Rhodnius prolixus not only has served as a model organism for the study of insect physiology, but also is a major vector of Chagas disease, an illness that affects approximately seven million people worldwide. We sequenced the genome of R. prolixus, generated assembled sequences covering 95% of the genome (similar to 702 Mb), including 15,456 putative protein-coding genes, and completed comprehensive genomic analyses of this obligate blood-feeding insect. Although immune-deficiency (IMD)-mediated immune responses were observed, R. prolixus putatively lacks key components of the IMD pathway, suggesting a reorganization of the canonical immune signaling network. Although both Toll and IMD effectors controlled intestinal microbiota, neither affected Trypanosoma cruzi, the causal agent of Chagas disease, implying the existence of evasion or tolerance mechanisms. R. prolixus has experienced an extensive loss of selenoprotein genes, with its repertoire reduced to only two proteins, one of which is a selenocysteine-based glutathione peroxidase, the first found in insects. The genome contained actively transcribed, horizontally transferred genes from Wolbachia sp., which showed evidence of codon use evolution toward the insect use pattern. Comparative protein analyses revealed many lineage-specific expansions and putative gene absences in R. prolixus, including tandem expansions of genes related to chemoreception, feeding, and digestion that possibly contributed to the evolution of a blood-feeding lifestyle. The genome assembly and these associated analyses provide critical information on the physiology and evolution of this important vector species and should be instrumental for the development of innovative disease control methods.

Se utilizó un modelo artificial de refugio para estudiar diversos aspectos de su uso por T. infestans. Estos insectos salen de sus refugios al comienzo de la escotofase para procurar alimento. Se muestra que la búsqueda de refugio ocurre al final de la fase oscura. El nivel de ayuno tiene una relación directamente proporcional con la actividad de búsqueda del hospedador entre la salida de refugio y la vuelta al mismo. Esto implica que los insectos ayunados se mantienen activos durante toda la fase oscura. Se describe un comportamiento de defecación, mediante el cual las vinchucas abandonan los refugios para eliminar sus deyecciones en proximidad de estos. Como consecuencia, se observa la acumulación de deyecciones en los accesos a refugios. Se demuestra que las heces actúan como marcas químicas de las inmediaciones del refugio, orientando a los insectos hacia éste. Explotando este comportamiento, se desarrollo un diseño muy sencillo de refugio artificial cebado, que es capaz de reclutar vinchucas a su interior. Pudo determinarse que la temperatura, y en particular la humedad relativa, son factores que afectan la elección de un refugio por parte de las vinchucas. Se presenta la primer trampa para vinchucas, asociada con cultivos de Saccharomices cerevisiae como cebos atrayentes. Dicha trampa cebada resultó altamente efectiva en ensayos de laboratorio, capturando al 50 % de los insectos presentes en una noche. En ensayos a campo se determinó la efectividad de la trampa, capturándose números significativos de vinchucas en periodos breves de tiempo. A model of artificial refuge was used to study different aspects of its exploitation by T. infestans. These insects get out from shelters at the beginning of the dark phase in order to find a host. We show that the search for refuges occurs at the end of the scotophase. The fasten interval has a direct relationship to the level of host searching activity during the interval between refuge outgoing and incoming. This means that fastened insects keep active during the whole night. A behaviour is described, by means of which the vinchucas go out from shelters in order to defecate in their vicinity. As a consequence, an accumulation of faecal droppings is observed at the refuge entrance. It is shown that dry faeces act as a chemical mark of the surroundings of the shelter orienting the insects toward the refuge. A simple baited artificial refuge was developed, capable to draw triatomines inside. It was demonstrated that the temperature and specially the relative humidity at the refuge, affect the selection of a shelter by the bugs, The first trap for triatomine bugs is presented, associated with cultures of Saccharomices cerevisiae that act as a bait improving dramatically the captures of bugs. That trap showed to be highly effective in laboratory assays, capturing 50 % of the present bugs in single night assays. In field trials, this trap captured significant numbers of bugs in one night assays. Fil: Lorenzo, Marcelo G.. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.