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The mosquito Aedes aegypti is distributed worldwide and is recognized as the primary vector for dengue in numerous countries. To investigate whether the fitness cost of a single DENV-1 isolate varies among populations, we selected four Ae. aegypti populations from distinct localities: Australia (AUS), Brazil (BRA), Pakistan (PAK), and Peru (PER). Utilizing simple methodologies, we concurrently assessed survival rates and fecundity. Overall, DENV-1 infection led to a significant decrease in mosquito survival rates, with the exception of the PER population. Furthermore, infected Ae. aegypti from PAK, the population with the lowest infection rate among those tested, exhibited a noteworthy reduction in egg laying. These findings collectively suggest that local mosquito-virus adaptations may influence dengue transmission in endemic settings.

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In Mexico, more than 30 species of triatomines, vectors of Trypanosoma cruzi, the etiological agent of Chagas disease, have been collected. Among them, Triatoma pallidipennis stands out for its wide geographical distribution, high infection rates and domiciliation. Local populations of triatomines have shown notable biological and behavioral differences, influencing their vectorial capacity. Six behaviors of epidemiological importance, namely, egg-to-adult development time, median number of blood meals to molt to the next instar, instar mortality rates, aggressiveness (delay in initiating a meal), feeding time and defecation delay, were evaluated in this study for six populations of T. pallidipennis. Those populations from central, western and southern Mexico were arranged by pairs with a combination of high (HP) and medium (MP) of Trypanosoma cruzi human infection and most (MFC) and low (CLF) collection frequencies: HP/MFC, HP/CLF, and MP/MFC. The development time was longer in HP/CLF populations (> 220 days). The median number of blood meals to molt was similar (7-9) among five of the six populations. Mortality rates were greater (> 40 %) in HP/CLF and one MP/MFC populations. All studied populations were aggressive but exhibited slight differences among them. The feeding times were similar (≥ 10 min) for all studied populations within instars, increasing as instars progressed. An irregular pattern was observed in defecation behaviors, with marked differences even between the two populations from the same pair. High percentages of young (57.3-87.9 %), and old (62.4-89.8 %) nymphs, of female (61.1-97.3 %) and male (65.7-93.1 %) of all the studied populations defecated quickly (while eating, immediately after finishing feeding or < 1 min postfeeding). Our results indicate that the HP/MFC populations are potentially highly effective vectors for transmitting T. cruzi infections, while HP/CLF populations are potentially less effective vectors T. cruzi infections.

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Vector control is still the recommended approach to avoid arbovirus outbreaks. Herein, we investigate oviposition preferences of Aedes aegypti (Diptera: Culicidae) females under a semi-field structure Rio de Janeiro, Brazil. For that, in Experiment 1, we used two settings: 'Single items', which included as containers drain, beer bottle, bucket, car tyre, water tank, and a potted Peace Lily (Spathiphyllum wallisii) in a saucer with water, or 'Multiple containers', as an urban simulation, in which one drain, two additional beer bottles, and an extra plant pot saucer were added. Experiment 2 (sensory cues) used five variations of potted plant, each one varying in the range of sensory cues known to attract gravid females to oviposition containers. Our results indicate that gravid Ae. aegypti prefer to oviposit close to the ground and in open water containers with organic compounds from plant watering. Domestic large artificial containers containing tap water received significantly fewer eggs, except for the car tyre, which exhibited as many eggs as the potted plant. We also show that visual (potted plant shape) and olfactory clues (odour of the plant or from water containing organic matter) were equally attractive separately as were these stimuli together.

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Antibiotic treatment has been used to enhance anopheline susceptibility to Plasmodium infection, because bacterial microbiota play a fundamental role in modulating the vector competence of mosquitoes that transmit Plasmodium parasites. However, few studies have examined the impact of antibiotic treatments on Plasmodium vivax sporogonic development in neotropical anopheline mosquitoes. Herein, we assessed the impact of antibiotic treatment on P. vivax development and survival in Anopheles darlingi, the main vector of malaria in the Amazon region. Female mosquitoes were treated continuously with antibiotics to impact the gut bacterial load and then tested for prevalence, infection intensity, and survival in comparison with untreated mosquitoes. Antibiotic-fed mosquitoes had not dramatic impact on P. vivax development previously observed in P. falciparum. However, antibiotic treatment increases mosquito survival, which is known to increase vectorial capacity. These findings raise questions about the effect of antibiotics on P. vivax development and survival in An. darlingi.

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BACKGROUND: The vector species in the Amazon River Basin are regionally and locally diverse, which makes it imperative to understand and compare their roles in malaria transmission to help select appropriate methods of intervention and evaluation. The major aim of this study was to measure the vectorial capacity of five Anopheles species in three neighbouring villages, for two Plasmodium parasite species affecting humans. METHODS: From 32 consecutive months of sampling in three villages, 1.5-7.0 km apart, on the Matapi River, Amapá State, Brazil, vectorial capacities (C) were estimated as time series for An. darlingi, An. marajoara, An. nuneztovari, An. triannulatus, and An. intermedius. Monthly parity measurements for each vector species were used to estimate daily survivorship and compared to estimates of survivorship from mark-release-recapture experiments. Gonotrophic cycle lengths were estimated through a time-series analysis of parity data, and durations of sporogony at study site temperatures for the two malaria parasite species were estimated from previous literature. RESULTS: The absolute abundances of five vector species were strongly tracked by the spatial variation in C among villages. Temporally, C varied between wet and dry seasons, with An. darlingi, An. marajoara and An. triannulatus exhibiting higher C in the dry season from August to December, and An. nuneztovari its highest C early in the rainy season in January and February. Anopheles intermedius exhibited higher C in the rainy season from April to June than in the dry season. Significant differences in overall survival for each independent variable, and a significant difference in C between wet and dry seasons, among villages, and among vector species for both Plasmodium falciparum and Plasmodium vivax. A generalized linear mixed model (GLMM) analysis by village showed significant effects of vector species on C in only one village, but significant effects of parasite species in all three. Although the GLMM analysis detected no significant parasite x vector species interaction effects on C, effects on C of spline regressions of C dynamics x vector species interactions were significant in all villages. CONCLUSIONS: These detailed analyses of entomological and parasitological variables revealed hidden complexities of malaria epidemiology at local scales in neighbouring riverine villages of the Amazon Region.

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Arbovirus epidemiology lacks efficient and timely surveillance systems with accurate outbreak alert signals. We devised a citywide integrated surveillance system combining entomologic, epidemiologic, and entomo-virologic data gathered during 2017-2020 in Foz do Iguaçu, Brazil. We installed 3,476 adult mosquito traps across the city and inspected traps every 2 months. We compared 5 entomologic indices: traditional house and Breteau indices for larval surveys and trap positivity, adult density, and mosquitoes per inhabitant indices for adult trapping. We screened for dengue, Zika, and chikungunya viruses in live adult Aedes aegypti mosquitoes collected from traps. Indices based on adult mosquito sampling had higher outbreak predictive values than larval indices, and we were able to build choropleth maps of infestation levels <36 h after each round of trap inspection. Locating naturally infected vectors provides a timely support tool for local public health managers to prioritize areas for intervention response to prevent virus outbreaks.

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Currently, DENV transmitted primarily by Aedes aegypti affects approximately one in three people annually. The spatio-temporal heterogeneity of vector infestation and the intensity of arbovirus transmission require surveillance capable of predicting an outbreak. In this work, we used data from 4 years of reported dengue cases and entomological indicators of adult Aedes collected from approximately 3500 traps installed in the city of Foz do Iguaçu, Brazil, to evaluate the spatial and temporal association between vector infestation and the occurrence of dengue cases. Entomological (TPI, ADI and MII) and entomo-virological (EVI) indexes were generated with the goal to provide local health managers with a transmission risk stratification that allows targeting areas for vector control activities. We observed a dynamic pattern in the evaluation; however, it was a low spatio-temporal correlation of Ae. aegypti and incidence of dengue. Independent temporal and spatial effects capture a significant portion of the signal given by human arbovirus cases. The entomo-virological index (EVI) significantly signaled risk in a few areas, whereas entomological indexes were not effective in providing dengue risk alert. Investigating the variation of biotic and abiotic factors between areas with and without correlation should provide more information about the local epidemiology of dengue.

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The information from the tick cattle microbiota suggests that the microbial populations may modulate a successful infection process of the tick-borne pathogens. Therefore, there is a need to know the microbial population and their interactions. In this mini-review, we present several examples of how microbiota regulates the survival of pathogens inside the tick and contributes to fitness, adaptation, and tick immunity, among others. The communication between the tick microbiota and the host microbiota is vital to understanding the pathogen transmission process. As part of the tick microbiota, the pathogen interacts with different microbial populations, including the microorganisms of the host microbiota. These interactions comprise a microsystem that regulates the vectorial capacity involved in tick-borne diseases. The knowledge we have about the vectorial capacity contributes to a better understanding of tick-borne pathogens. Additionally, using approaches based on multi-omics strategies applied to studying the microbiota and its microbiome allows the development of strategies to control ticks. The results derived from those studies reveal the dynamics of the microbiota and potential targets for anti-tick vaccine development. In this context, the anti-microbiota vaccines have emerged as an alternative with a good prognosis. Some strategies developed to control other arthropods vectors, such as paratransgenesis, could control ticks and tick-borne diseases.

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Three behaviors of epidemiological importance, namely feeding latency, feeding duration and defecation latency, for six populations of Meccus phyllosomus longipennis (Usinger) from areas of central, western and north-central Mexico with high (HP) and low (LP) prevalence of Trypanosoma cruzi (Chagas) human infection were evaluated in this study. The median feeding latency (the time taken to begin feeding) was highly variable between instars. Within-instar comparisons showed that at least 65% of the LP populations (N3 to adult) started to feed significantly (P < 0.05) later than the HP population, with N1 showing no difference, and N2 from LP populations feeding sooner than those from HP populations. The six populations had similar median feeding durations within instars. A higher (P < 0.05) percentage of the instars from HP populations defecated faster than the respective instars from the three LP populations. Approximately 25% of the young nymphs (N1 to N3) and females in the HP populations defecated < 2 min postfeeding, compared with 4%-6% of the young nymphs and 1.3%-3% of females in the LP populations. Moreover, 17.7%-38.8% of the older nymphs (N4 to N5) in the HP populations and 6.8%-13.4% in the LP populations defecated during or immediately after feeding. Our results indicate that the HP populations have a greater potential than the LP populations to transmit T. cruzi infections, which may underlie the differences in the prevalence of T. cruzi infection in some areas where M. p. longipennis is currently distributed.

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Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of Aedes aegypti fed directly on viremic human and non-human primates (NHPs). We blood-fed Ae. aegypti from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation. Although viremia extended up to eight days post monkey inoculation, only mosquitoes fed on the day of the peak of viremia, recorded on day two, became infected. The influence of SOF treatment could not be assessed because the drug was administered just after mosquito feeding on day two. The global infection, dissemination and transmission rates were quite low (4.09%, 1.91% and 0.54%, respectively); no mosquito was infected when viremia was below 1.26 × 105 RNA copies/mL. In conclusion, Ae. aegypti vector competence for ZIKV from macaques is low, likely to be due to low viral load and the short duration of ZIKV viremia in primates suitable for infecting susceptible mosquitoes. If ZIKV infection in human and macaques behaves similarly, transmission of the Zika virus in nature is most strongly affected by vector density.

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Rapid and significant range expansion of both Zika virus (ZIKV) and its Aedes vector species has resulted in ZIKV being declared a global health threat. Mean temperatures are projected to increase globally, likely resulting in alterations of the transmission potential of mosquito-borne pathogens. To understand the effect of diurnal temperature range on the vectorial capacity of Ae. aegypti and Ae. albopictus for ZIKV, longevity, blood-feeding and vector competence were assessed at two temperature regimes following feeding on infectious blood meals. Higher temperatures resulted in decreased longevity of Ae. aegypti [Log-rank test, χ2, df 35.66, 5, P < 0.001] and a decrease in blood-feeding rates of Ae. albopictus [Fisher's exact test, P < 0.001]. Temperature had a population and species-specific impact on ZIKV infection rates. Overall, Ae. albopictus reared at the lowest temperature regime demonstrated the highest vectorial capacity (0.53) and the highest transmission efficiency (57%). Increased temperature decreased vectorial capacity across groups yet more significant effects were measured with Ae. aegypti relative to Ae. albopictus. The results of this study suggest that future increases in temperature in the Americas could significantly impact vector competence, blood-feeding and longevity, and potentially decrease the overall vectorial capacity of Aedes mosquitoes in the Americas.

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Vectorial capacity (VC), as a concept that describes the potential of a vector to transmit a pathogen, has had historical problems related to lacks in dimensional significance and high error propagation from parameters that take part in the model to output. Hence, values estimated with those equations are not sufficiently reliable to consider in control strategies or vector population study. In this paper, we propose a new VC model consistent at dimensional level, i.e., the definition and the equation of VC have same and consistent units, with a parameter estimation method and mathematical structure that reduces the uncertainty in model output, using as a case of study an Aedes aegypti population of the municipality of Bello, Colombia. After a literature review, we selected one VC equation following biological, measurability and dimensional criteria, then we rendered a local and global sensitivity analysis, identifying the mortality rate of mosquitoes as a target component of the equation. Thus, we studied the Weibull and Exponential distributions as probabilistic models that represent the expectation of mosquitoes infective life, intending to include the best distribution in a selected VC structure. The proposed mortality rate estimation method includes a new parameter that represents an increase or decrease in vector mortality, as it may apply. We noticed that its estimation reduces the uncertainty associated with the expectation of mosquitoes' infective life expression, which also reduces the output range and variance in almost a half.

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RESUMEN I: Para mantener la reducción de la malaria, se promueven iniciativas que aceleren la eliminación. En años recientes con la reducción sostenida de la malaria, Colombia hacia el 2021 propone su eliminación en áreas urbanas por lo cual se requieren investigaciones para este desafío O: Establecer la situación epidemiológica de la transmisión de malaria urbana/peri en Guapi 2011-2015 y describir los desafíos en capacidad vectorial, receptividad, infectividad y vulnerabilidad. M: Se realizó un estudio descriptivo, se obtuvieron datos epidemiológicos, entomológicos, parasitológicos, de servicios de salud y socio económicos mediante entrevistas y fuentes secundarias. Con la información se realizaron análisis uni y bivariados, se aplicaron formatos de eliminación de malaria propuestos por la Organización Mundial de la Salud y se analizaron brechas. R: Se notificaron 1097 casos, 39,5% se registraron en el área urbana/peri, y a su vez, el 68% de éstos se concentraron en tres barrios. En capacidad vectorial se identificó como vector primario a anopheles albimanus, con susceptibilidad a los insecticidas, múltiples criaderos y estrategias de instalación de mosquiteros con altas coberturas; en infectividad se encontró predominio de infecciones por p, falciparum, oportunidad de consulta en las primeras 48 horas del 48,1% y automedicación; en vulnerabilidad los casos no urbanos representaron 60,5 % del total. C: La malaria se caracterizó por ser de baja intensidad, focalizada y con picos. Hay significativa receptividad, en infectividad hay retrasos de oportunidad de consulta y existe alta vulnerabilidad por población migrante.

ABSTRACT I: To maintain the reduction of malaria, initiatives that accelerate the elimination are promoted. In recent years with the sustained reduction of malaria, Colombia by 2021 proposes its elimination in urban areas, which requires research for this challenge O: Establish the epidemiological situation of transmission of urban / peri malaria in Guapi 2011-2015 and describe the challenges in vector capacity, receptivity, infectivity and vulnerability. M: A descriptive study was conducted, epidemiological, entomological, parasitological, health and socioeconomic services were obtained through interviews and secondary sources. With the information, univariate and bivariate analyzes were carried out, malaria elimination formats proposed by the World Health Organization were applied and gaps were analyzed. A: 1097 cases were notified, 39.5% were registered in the urban / peri area, and in turn, 68% of these were concentrated in three neighborhoods. In vectorial capacity anopheles albimanus was identified as the primary vector with susceptibility to insecticides, multiple hatcheries and strategies for installing mosquito nets with high coverage; In infectivity, predominance of p. falciparum, 48.1% consultation opportunity in the first 48 hours and self-medication; in vulnerability, non-urban cases represented 60.5% of the total. C: Malaria was characterized by being of low intensity, focused and with spikes. There is significant receptivity, in infectiousness there are delays in the opportunity of consultation and there is high vulnerability due to migrant population.

RESUMO I: Para manter a redução da malária, são promovidas iniciativas que aceleram a eliminação. Nos últimos anos, com a redução sustentada da malária, a Colômbia propõe, até 2021, sua eliminação nas áreas urbanas, o que requer pesquisa para esse desafio O: Estabelecer a situação epidemiológica da transmissão da malária urbana / peri-Guapi 2011-2015 e descrever os desafios em capacidade de vetores, receptividade, infecciosidade e vulnerabilidade. M: Estudo descritivo, epidemiológico, entomológico, parasitológico, de saúde e socioeconómico, obtido por meio de entrevistas e fontes secundárias. Com as informações, foram realizadas análises univariadas e bivariadas, os formatos de eliminação de malária propostos pela Organização Mundial da Saúde foram aplicados e as lacunas foram analisadas. R: 1097 casos foram notificados, 39,5% foram registrados na área urbana / peri e, por sua vez, 68% destes foram concentrados em três bairros. Em capacidade vetorial, anopheles albimanus foi identificado como vetor primário, com suscetibilidade a inseticidas, múltiplos incubatórios e estratégias para a instalação de redes mosquiteiras com alta cobertura; Na infectividade, predomínio de p. falciparum, 48,1% de oportunidade de consulta nas primeiras 48 horas e automedicação; em vulnerabilidade, os casos não urbanos representaram 60,5% do total. C: A malária foi caracterizada por ser de baixa intensidade, focada e com picos. Há uma receptividade significativa, na infecciosidade há atrasos na oportunidade de consulta e há alta vulnerabilidade devido à população migrante.

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Malaria transmission in South America is overwhelmingly located in the Amazon region with limited cases outside that biome. A key factor in the mitigation of malaria transmission is the determination of vector diversity and bionomics in endemic areas. Anopheles mosquitoes were collected in four different landscapes of Cruzeiro do Sul-Acre, the current area with highest malaria transmission in Brazil. We performed adult mosquito collections every three months over two years and associated vector occurrence with local abiotic factors. A total of 1,754 Anopheles belonging to nine species were collected, but only four of them (An. albitarsis s.l. Lynch-Arribalzaga, An. braziliensis Chagas, An. peryassui Dyar and Knab, and An. triannulatus Neiva and Pinto) represented 77.1% of the total. Vector density and diversity was uneven across field sites and collection periods. Higher Anopheles abundance (54.8%) and richness were observed in a deforested palm tree area (IFC), with An. braziliensis the most frequent mosquito (40.5%). Only 7.3% of mosquitoes were collected in the SAB village, but 66.4% of them were An. darlingi and An. oswaldoi, species often regarded as primary and secondary vectors of malaria in the Amazon region. A distinct biting preference was observed between 18:00-19:40. The distance from the nearest breeding site and minimum temperature explained 41.6% of the Anopheles community composition. Our data show that the Anopheles species composition may present great variation on a microgeographic scale.

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Pyrethroid resistance has been detected in Triatoma infestans (Klug) (Hemiptera: Reduviidae) specimens from different areas of Argentina and Bolivia. Genes conferring resistance can have a pleiotropic effect with epidemiological and evolutionary consequences. This research studied excretion/defecation patterns in deltamethrin-resistant T. infestans in order to elucidate its biological performance, adaptive consequences and role in the transmission of Chagas' disease. One deltamethrin-susceptible strain and two deltamethrin-resistant strains were used. Fifth-instar nymphs were fed ad libitum and their defecations recorded during and after the first or second feeding in the stadium. Resistant insects began to defecate later, defecated less, showed a lower proportion of defecating individuals and lower defecation indices compared with susceptible insects during the first hour after feeding. The number of bloodmeals in the stadium did not affect the main variables determining the pattern of defecation. The present study suggests that alterations in the excretion/defecation pattern in resistant insects entail an adaptive cost and, considering only this pattern, determine a lower capacity for transmission of Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae) compared with susceptible insects.

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BACKGROUND: Chagas disease, or American trypanosomiasis, is an important neglected tropical illness caused by the flagellate protozoan Trypanosoma cruzi, which is primarily transmitted to humans by hematophagous insects of the subfamily Triatominae. Although knowledge on triatomine movement capabilities at the micro-geographical scale is of fundamental importance concerning the development of effective vector control strategies, it remains a poorly understood subject. Furthermore, survival rates and size estimates of natural populations are important topics to consider when evaluating transmission intensity. RESULTS: The movement of adult Triatoma sordida within the peridomestic area of a rural Brazilian household was evaluated via mark-release-recapture assays. A total of 210 insects had their pronota marked with fluorescent dyes and were released at different distances from the chicken coop (two, five, ten and 20 m), and from the horse corral (27, 32, 35, 46 and 56 m). Recaptures occurred in three consecutive 15-day intervals. Specimens were successfully recaptured at all distances up to 32 m. Bayesian models were used to estimate recapture probability, survival rates (males vs females) and population size. Although recapture probability was inversely proportional to distance for both sexes, females were more affected by increased distance. On the other hand, no significant difference was detected in the survival rates between males and females in a 15-day period. Fisher-Ford and Bayesian models gave more accurate population size estimates than Lincoln method. CONCLUSIONS: Triatoma sordida adults were able to cover a distance of 32 m in 45 days. Recapture data modelling reveals that male dispersal was more effective suggesting that T. sordida males are more likely to contribute as potential colonizers of the peridomestic environment. Increasing the distance between the peridomestic structures and the sylvatic environment as much as possible appears to be a simple and feasible recommendation to reduce the contact rate between humans and infected bugs and ultimately Chagas disease transmission.

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A Zika virus (ZIKV) pandemic started soon after the first autochthonous cases in Latin America. Although Aedes aegypti is pointed as the primary vector in Latin America, little is known about the fitness cost due to ZIKV infection. We investigated the effects of ZIKV infection on the life-history traits of Ae. aegypti females collected in three districts of Rio de Janeiro, Brazil (Barra, Deodoro, and Porto), equidistant ~25 km each other. Aedes aegypti mosquitoes were classified into infected (a single oral challenge with ZIKV) and superinfected (two ZIKV-infected blood meals spaced by 7 days each other). ZIKV infection reduced Ae. aegypti survival in two of the three populations tested, and superinfection produced a sharper increase in mortality in one of those populations. We hypothesized higher mortality with the presence of more ZIKV copies in Ae. aegypti females from Porto. The number of eggs laid per clutch was statistically similar between vector populations and infected and uninfected mosquitoes. Infection by ZIKV not affected female oviposition success. ZIKV infection impacted Ae. aegypti vectorial capacity by reducing its lifespan, although female fecundity remained unaltered. The outcome of these findings to disease transmission intensity still needs further evaluation.

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A dimensional analysis of the classical equations related to the dynamics of vector-borne infections is presented. It is provided a formal notation to complete the expressions for the Ross' Threshold Theorem, the Macdonald's basic reproduction "rate" and sporozoite "rate", Garret-Jones' vectorial capacity and Dietz-Molineaux-Thomas' force of infection. The analysis was intended to provide a formal notation that complete the classical equations proposed by these authors.

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The study was undertaken in eight endemic districts of Orissa, India, to find the members of the species complexes of Anopheles culicifacies and Anopheles fluviatilis and their distribution patterns. The study area included six forested districts (Keonjhar, Angul, Dhenkanal, Ganjam, Nayagarh and Khurda) and two non-forested coastal districts (Puri and Jagatsingpur) studied over a period of two years (June 2007-May 2009). An. culicifacies A, B, C and D and An. fluviatilis S and T sibling species were reported. The prevalence of An. culicifacies A ranged from 4.2-8.41 percent, B from 54.96-76.92 percent, C from 23.08-33.62 percent and D from 1.85-5.94 percent (D was reported for the first time in Orissa, except for occurrences in the Khurda and Nayagarh districts). The anthropophilic indices (AI) were 3.2-4.8 percent, 0.5-1.7 percent, 0.7-1.37 percent and 0.91-1.35 percent for A, B, C and D, respectively, whereas the sporozoite rates (SR) were 0.49-0.54 percent, 0 percent, 0.28-0.37 percent and 0.41-0.46 percent for A, B, C and D, respectively. An. fluviatilis showed a similarly varied distribution pattern in which S was predominant (84.3 percent overall); its AI and SR values ranged from 60.7-90.4 percent and 1.2-2.32 percent, respectively. The study observed that the co-existence of potential vector sibling species of An. culicifacies (A, C and D) and An. fluviatilis S (> 50 percent) was responsible for the high endemicity of malaria in forested districts such as Dhenkanal, Keonjhar, Angul, Ganjam, Nayagarh and Khurda (> 5 percent slide positivity rate). Thus, the epidemiological scenario for malaria is dependent on the distribution of the vector sibling species and their vectorial capacity.

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Different urban structures might affect the life history parameters of Aedes aegypti and, consequently, dengue transmission. Container productivity, probability of daily survival (PDS) and dispersal rates were estimated for mosquito populations in a high income neighbourhood of Rio de Janeiro. Results were contrasted with those previously found in a suburban district, as well as those recorded in a slum. After inspecting 1,041 premises, domestic drains and discarded plastic pots were identified as the most productive containers, collectively holding up to 80 percent of the total pupae. In addition, three cohorts of dust-marked Ae. aegypti females were released and recaptured daily using BGS-Traps, sticky ovitraps and backpack aspirators in 50 randomly selected houses; recapture rate ranged from 5-12.2 percent within cohorts. PDS was determined by two models and ranged from 0.607-0.704 (exponential model) and 0.659-0.721 (non-linear model), respectively. Mean distance travelled varied from 57-122 m, with a maximum dispersal of 263 m. Overall, lower infestation indexes and adult female survival were observed in the high income neighbourhood, suggesting a lower dengue transmission risk in comparison to the suburban area and the slum. Since results show that urban structure can influence mosquito biology, specific control strategies might be used in order to achieve cost-effective Ae. aegypti control.

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