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BACKGROUND: Dengue (DENV) transmission is endemic throughout coastal Ecuador, showing heterogeneous incidence patterns in association with fine-scale variation in Aedes aegypti vector populations and other factors. Here, we investigated the impact of micro-climate and neighbourhood-level variation in urbanization on Aedes abundance, resting behaviour and associations with dengue incidence in two endemic areas. METHODOLOGY/PRINCIPAL FINDINGS: Aedes aegypti were collected in Quinindé and Portoviejo, two urban cantons with hyperendemic dengue transmission in coastal Ecuador. Aedes vectors were sampled in and around houses within urban and peri-urban neighbourhoods at four time periods. We tested for variation in vector abundance and resting behaviour in relation to neighbourhood urbanization level and microclimatic factors. Aedes abundance increased towards the end of the rainy season, was significantly higher in Portoviejo than in Quinindé, and in urban than in peri-urban neighbourhoods. Aedes vectors were more likely to rest inside houses in Portoviejo but had similar abundance in indoor and outdoor resting collections in Quinindé. Over the study period, DENV incidence was lower in Quinindé than in Portoviejo. Relationships between weekly Ae. aegypti abundance and DENV incidence were highly variable between trapping methods; with positive associations being detected only between BG-sentinel and outdoor Prokopack collections. CONCLUSIONS/SIGNIFICANCE: Aedes aegypti abundance was significantly higher in urban than peri-urban neighbourhoods, and their resting behaviour varied between study sites. This fine-scale spatial heterogeneity in Ae. aegypti abundance and behaviour could generate site-specific variation in human exposure and the effectiveness of indoor-based interventions. The trap-dependent nature of associations between Aedes abundance and local DENV incidence indicates further work is needed to identify robust entomological indicators of infection risk.

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An updated list of biting midges of the genus Culicoides inhabiting Ecuador is provided. Entomological investigations were carried out from July 2010 to May 2019 using CDC light traps in three Ecuadorian regions (Amazon basin, Andean (foothills and highlands) and Pacific Coast). A total of 12,073 Culicoides specimens from seven subgenera and nine species groups were collected. More species and higher variation were found in the Amazon basin than in either of the Andes regions or coastal sites. A total of 53 species were identified. Of these, 15 are herein reported as new species records for Ecuador: Culicoides acotylus Lutz, C. aitkeni Wirth & Blanton, C. benarrochi Ortiz & Mirsa, C. carvalhoi Wirth & Blanton, C. freitasi Wirth & Blanton, C. ginesi Ortíz, C. lopesi Barretto, C. lyrinotatus Wirth & Blanton, C. profundus Santarém, Felippe-Bauer & Trindade, C. pseudoreticulatus Santarém, Felippe-Bauer & Castellón, C. quasiparaensis Clastrier, C. vernoni Wirth & Blanton, C. youngi Wirth & Barreto and two new species. Our results show that the updated list of the Ecuadorian Culicoides fauna comprises 70 species. This inventory highlights the presence of species that have been incriminated as vectors of disease elsewhere in animals and humans, mainly C. insignis and C. paraensis.

Title: Une liste actualisée de la faune des Culicoides (Diptera, Ceratopogonidae) de l'Équateur. Abstract: Une liste actualisée des Culicoides vivant en Équateur est fournie. Des enquêtes entomologiques ont été menées de juillet 2010 à mai 2019 à l'aide de pièges lumineux CDC dans trois régions équatoriennes (le bassin amazonien, les Andes (piémont et hautes terres) et la côte Pacifique). Au total, 12 073 spécimens de Culicoides de sept sous-genres et neuf groupes d'espèces ont été collectés. Plus d'espèces et une variation plus élevée ont été trouvées dans le bassin amazonien que dans les régions des Andes ou les sites côtiers. Au total, 53 espèces ont été identifiées. Parmi celles-ci, 15 sont signalées ici comme nouvelles espèces pour l'Équateur : Culicoides acotylus Lutz, C. aitkeni Wirth & Blanton, C. benarrochi Ortiz & Mirsa, C. carvalhoi Wirth & Blanton, C. freitasi Wirth & Blanton, C. ginesi Ortíz, C. lopesi Barretto, C. lyrinotatus Wirth & Blanton, C. profundus Santarém, Felippe-Bauer & Trindade, C. pseudoreticulatus Santarém, Felippe-Bauer & Castellón, C. quasiparaensis Clastrier, C. vernoni Wirth & Blanton, C. youngi Wirth & Barreto et deux nouvelles espèces. Nos résultats montrent que la liste actualisée de la faune culicoïde équatorienne comprend 70 espèces. Cet inventaire met en évidence la présence d'espèces qui ont été incriminées ailleurs comme vecteurs de maladies chez l'animal et l'homme, principalement C. insignis et C. paraensis.

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BACKGROUND: Most sand fly species are located in the Americas; some act as vectors of leishmaniasis and other human diseases. In Bolivia, about 25% of Neotropical species have been identified, and only a few have been implicated as vectors of cutaneous and visceral leishmaniasis. A new species of anthropophilic sand fly from the sub-Andean region of Alto Beni is described herein. METHODS: A large systematic entomological survey was carried out in a subtropical humid forest located in the Marimonos mountain range, at around 900 m altitude, in the municipality of Palos Blancos, Sud Yungas Province, Department of La Paz, Bolivia. Sand flies were captured over a period of 26 months between January 1982 and February 1984, at the ground and canopy level, using both CDC light traps and protected human bait. A total of 24,730 sand flies were collected on the ground, distributed in 16 species, and 3259 in the canopy, with eight species. One of these species was labeled as Pintomia (Pifanomyia) nevesi, although certain morphological features allowed us to doubt that it was that taxon. To define the identity of this sand fly, a re-evaluation (this work) was recently carried out through morphological analyses and measurements of the available specimens mounted on Euparal, previously labeled as Pi. (Pif.) nevesi. RESULTS: Based on the morphological traits and measurements, the re-evaluated specimens were definitively identified as a new sand fly species, Pintomyia (Pifanomyia) veintemillasi, closely related to Pi. (Pif.) nevesi and Pintomyia (Pifanomyia) maranonensis within the Evansi series. This new sand fly was the third most numerous anthropophilic species at the floor (6.2%) and the second most numerous anthropophilic at the canopy (35.1%). CONCLUSIONS: A new anthropophilic sand fly species is described as Pi. (Pif.) veintemillasi n. sp. This sand fly species was caught at about 900 m altitude in the Marimonos mountain range, a highly endemic area for cutaneous and mucosal leishmaniasis due to Leishmania (Viannia) braziliensis. Therefore, this species could be involved in the leishmaniasis transmission in the sub-Andean foothills of Alto Beni, Department of La Paz, Bolivia.

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Population adoption of social distancing measures during the COVID-19 pandemic is at times deficient, increasing the risk of SARS-CoV-2 transmission. Healthcare workers and those living in areas of intense transmission may benefit from implementing biosafety measures in their daily lives. A mixed-methods approach, combining components of single negotiation text and the Delphi method, was used to create a COVID-19 biosafety-at-home protocol. A consensus building coordinator liaised with 12 experts to develop the protocol over 11 iterations. Experts had more than 200 years of combined experience in epidemiology, virology, infectious disease prevention, and public health. A flyer, created from the final protocol, was professionally designed and initially distributed via social media and institutional websites/emails in Ecuador beginning on May 2, 2020. Since then, it has been distributed in other countries, reaching ∼7,000 people. Translating research laboratory biosafety measures for the home/street environment might be challenging. The biosafety-at-home flyer addresses this challenge in a user-friendly format.

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BACKGROUND: Entomological monitoring of Aedes vectors has largely relied on surveillance of larvae, pupae and non-host-seeking adults, which have been poorly correlated with human disease incidence. Exposure to mosquito-borne diseases can be more directly estimated using human landing catches (HLC), although this method is not recommended for Aedes-borne arboviruses. We evaluated a new method previously tested with malaria vectors, the mosquito electrocuting trap (MET) as an exposure-free alternative for measuring landing rates of Aedes mosquitoes on people. Aims were to (i) compare the MET to the BG-sentinel (BGS) trap gold standard approach for sampling host-seeking Aedes vectors; and (ii) characterize the diel activity of Aedes vectors and their association with microclimatic conditions. METHODS: The study was conducted over 12 days in Quinindé (Ecuador) in May 2017. Mosquito sampling stations were set up in the peridomestic area of four houses. On each day of sampling, each house was allocated either a MET or a BGS trap, which were rotated amongst the four houses daily in a Latin square design. Mosquito abundance and microclimatic conditions were recorded hourly at each sampling station between 7:00-19:00 h to assess variation between vector abundance, trapping methods, and environmental conditions. All Aedes aegypti females were tested for the presence of Zika (ZIKV), dengue (DENV) and chikungunya (CHIKV) viruses. RESULTS: A higher number of Ae. aegypti females were found in MET than in BGS collections, although no statistically significant differences in mean Ae. aegypti abundance between trapping methods were found. Both trapping methods indicated female Ae. aegypti had bimodal patterns of host-seeking, being highest during early morning and late afternoon hours. Mean Ae. aegypti daily abundance was negatively associated with daily temperature. No infection by ZIKV, DENV or CHIKV was detected in any Aedes mosquitoes caught by either trapping method. CONCLUSION: We conclude the MET performs at least as well as the BGS standard and offers the additional advantage of direct measurement of per capita human-biting rates. If detection of arboviruses can be confirmed in MET-collected Aedes in future studies, this surveillance method could provide a valuable tool for surveillance and prediction on human arboviral exposure risk.

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Dengue fever is an emerging infectious disease in the Galápagos Islands of Ecuador, with the first cases reported in 2002 and subsequent periodic outbreaks. We report results of a 2014 pilot study conducted in Puerto Ayora (PA) on Santa Cruz Island, and Puerto Baquerizo Moreno (PB) on San Cristobal Island. To assess the socio-ecological risk factors associated with dengue and mosquito vector presence at the household level, we conducted 100 household surveys (50 on each island) in neighborhoods with prior reported dengue cases. Adult mosquitoes were collected inside and outside the home, larval indices were determined through container surveys, and heads of households were interviewed to determine demographics, self-reported prior dengue infections, housing conditions, and knowledge, attitudes, and practices regarding dengue. Multi-model selection methods were used to derive best-fit generalized linear regression models of prior dengue infection, and Aedes aegypti presence. We found that 24% of PB and 14% of PA respondents self-reported a prior dengue infection, and more PB homes than PA homes had Ae. aegypti. The top-ranked model for prior dengue infection included several factors related to human movement, household demographics, access to water quality issues, and dengue awareness. The top-ranked model for Ae. aegypti presence included housing conditions, mosquito control practices, and dengue risk perception. This is the first study of dengue risk and Ae. aegypti presence in the Galápagos Islands.

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The number of recorded phlebotomine sand fly species in Ecuador has nearly doubled during the past 20 years as a result of surveys. In 2005, a sand fly survey of two localities, Tiputini in the Amazon rain forest and Paraiso Escondido in the Pacific coastal lowland forest, resulted in the capture of 25 species. New records for Ecuador consisted of five species from the Amazonian region and one from Paraiso Escondido. The Amazonian species were Nyssomyia richardwardi (Ready and Fraiha), Psathyromyia dreisbachi (Causey and Damasceno), Psathyromyia runoides (Fairchild and Hertig), Trichophoromyia pabloi (Barretto, Burbano and Young), and Trichopygomyia witoto (Young and Morales). The Pacific coastal lowland species was Psathyromyia punctigeniculata (Floch and Abonnenc).

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Azotobacter vinelandii is a nitrogen-fixing soil bacterium that undergoes differentiation to form cysts resistant to desiccation. Upon encystment, this bacterium becomes non-motile. As in enteric bacteria, motility in A. vinelandii occurs through the use of peritrichous flagella. Pseudomonas aeruginosa, a phylogenetically close relative of A. vinelandii, possesses a single polar flagellum. The FlhDC proteins are the master regulators of flagella and motility in enterobacteria, whereas FleQ is the master regulator in P. aeruginosa, and it is under AlgU (sigmaE) negative control. At present, nothing is known about the organization and expression of flagella genes in A. vinelandii. Here, we identified the flagella gene cluster of this bacterium. Homologues of the master regulatory genes flhDC and fleQ are present in A. vinelandii. Inactivation of flhDC, but not fleQ, impaired flagella biogenesis and motility. We present evidence indicating that a negative effect of the AlgU sigma factor on flhDC expression causes loss of motility in A. vinelandii, and that CydR (a homologue of Fnr) is under AlgU control and has a negative effect on flhDC expression. Taken together, these results suggest the existence of a cascade consisting of AlgU and CydR that negatively controls expression of flhDC; the results also suggest that the block in flagella synthesis under encystment conditions centres on flhDC repression by the AlgU-CydR cascade.

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