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Sample records for adult mosquito population

  1. The Temporal Spectrum of Adult Mosquito Population Fluctuations: Conceptual and Modeling Implications

    PubMed Central

    Jian, Yun; Silvestri, Sonia; Brown, Jeff; Hickman, Rick; Marani, Marco

    2014-01-01

    An improved understanding of mosquito population dynamics under natural environmental forcing requires adequate field observations spanning the full range of temporal scales over which mosquito abundance fluctuates in natural conditions. Here we analyze a 9-year daily time series of uninterrupted observations of adult mosquito abundance for multiple mosquito species in North Carolina to identify characteristic scales of temporal variability, the processes generating them, and the representativeness of observations at different sampling resolutions. We focus in particular on Aedes vexans and Culiseta melanura and, using a combination of spectral analysis and modeling, we find significant population fluctuations with characteristic periodicity between 2 days and several years. Population dynamical modelling suggests that the observed fast fluctuations scales (2 days-weeks) are importantly affected by a varying mosquito activity in response to rapid changes in meteorological conditions, a process neglected in most representations of mosquito population dynamics. We further suggest that the range of time scales over which adult mosquito population variability takes place can be divided into three main parts. At small time scales (indicatively 2 days-1 month) observed population fluctuations are mainly driven by behavioral responses to rapid changes in weather conditions. At intermediate scales (1 to several month) environmentally-forced fluctuations in generation times, mortality rates, and density dependence determine the population characteristic response times. At longer scales (annual to multi-annual) mosquito populations follow seasonal and inter-annual environmental changes. We conclude that observations of adult mosquito populations should be based on a sub-weekly sampling frequency and that predictive models of mosquito abundance must include behavioral dynamics to separate the effects of a varying mosquito activity from actual changes in the abundance of the

  2. The temporal spectrum of adult mosquito population fluctuations: conceptual and modeling implications.

    PubMed

    Jian, Yun; Silvestri, Sonia; Brown, Jeff; Hickman, Rick; Marani, Marco

    2014-01-01

    An improved understanding of mosquito population dynamics under natural environmental forcing requires adequate field observations spanning the full range of temporal scales over which mosquito abundance fluctuates in natural conditions. Here we analyze a 9-year daily time series of uninterrupted observations of adult mosquito abundance for multiple mosquito species in North Carolina to identify characteristic scales of temporal variability, the processes generating them, and the representativeness of observations at different sampling resolutions. We focus in particular on Aedes vexans and Culiseta melanura and, using a combination of spectral analysis and modeling, we find significant population fluctuations with characteristic periodicity between 2 days and several years. Population dynamical modelling suggests that the observed fast fluctuations scales (2 days-weeks) are importantly affected by a varying mosquito activity in response to rapid changes in meteorological conditions, a process neglected in most representations of mosquito population dynamics. We further suggest that the range of time scales over which adult mosquito population variability takes place can be divided into three main parts. At small time scales (indicatively 2 days-1 month) observed population fluctuations are mainly driven by behavioral responses to rapid changes in weather conditions. At intermediate scales (1 to several month) environmentally-forced fluctuations in generation times, mortality rates, and density dependence determine the population characteristic response times. At longer scales (annual to multi-annual) mosquito populations follow seasonal and inter-annual environmental changes. We conclude that observations of adult mosquito populations should be based on a sub-weekly sampling frequency and that predictive models of mosquito abundance must include behavioral dynamics to separate the effects of a varying mosquito activity from actual changes in the abundance of the

  3. Spatiotemporal investigation of adult mosquito (Diptera: Culicidae) populations in an eastern Iowa county, USA.

    PubMed

    DeGroote, John; Mercer, David R; Fisher, Jeffrey; Sugumaran, Ramanathan

    2007-11-01

    Landscape and climatic factors regulate distributions of mosquitoes (Diptera: Culicidae) over time and space. The anthropogenic control of mosquito populations is often carried out at a local administrative scale, and it is applied based on the relevant agency's experiential knowledge rather than systematic analysis of spatial and temporal data. To address this shortcoming, a spatial and temporal analysis of landscape and climatic parameters in relation to mosquito populations in Black Hawk County, IA, USA, has been carried out. Adult mosquito sampling took place using CDC light traps from May to August 2003 in representative landscapes. Mosquitoes were identified to species level with Aedes trivittatus (Coquillet) and Aedes vexans (Meigen) dominating the collection totals. The best publicly available spatial data on landscape and demographic attributes were collated and included land cover, human census, soils, floodplain, elevation, wetlands, hydrography, roads, and vegetation indices derived from satellite imagery. Spatial processing was carried out to organize landscape attributes for statistical comparison with abundance data from the potentially important West Nile virus (family Flaviviridae, genus Flavivirus, WNV) vector species Ae. vexans and Ae. trivittatus. Landscape parameters shown to be significantly correlated with mosquito counts included soil hydrological properties, presence in floodplain, wetland areas, and deciduous and bottomland forest cover. Data on temperature and precipitation were used to investigate the climatic influence on the temporal occurrence of mosquito population abundances. Late spring rain provided ample moisture for mosquito development, but low temperatures delayed widespread emergence of Ae. trivittatus and Ae. vexans until June 2003. Landscape and climatic impacts on adult mosquito population distributions were demonstrated, and these results could form the basis for the development of a spatiotemporal modeling framework that

  4. Measurement, analysis, and depiction of activity in adult mosquito populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Globalization, open trading practices, and climate change increase the likelihood of introduction of exotic mosquito species. These mosquitoes may harbor disease agents that threaten public and animal health. Successful containment and eradication of exotic mosquito species and (in the case of exo...

  5. Reduced productivity in adult yellowfever mosquito (Diptera: Culicidae) populations

    SciTech Connect

    Rodriguez, P.H.; Hamm, W.J.; Garcia, F.; Garcia, M.; Schirf, V.

    1989-04-01

    Male and female Aedes aegypti (L.) mosquitoes of the laboratory strain ROCK were irradiated with 130 mw of argon 514.5 nm laser microbeams for 0.04, 0.25, 0.4, and 0.5 s, respectively. Egg production, percentage hatch, and productivity (average number of adults surviving after 3 wk) were used to assess mutagenic effects. Mortality was high for males in all laser radiation groups and increased with time of exposure. Except for the group treated for 0.25 s, significant reductions in total F1 progeny also were demonstrated for all other experimentals when male parents were exposed to laser radiation. Females showed a high mortality when subjected to 0.4- and 0.5-s laser radiation. No F1 progeny were produced when parental females were exposed for 0.25, 0.4, and 0.5 s. Numbers of F1 progeny from females exposed to 0.04 s of laser radiation were significantly reduced. A comparison of weekly mean number of progeny showed that the important differences in productivity occurred during the first and second week, respectively, when either male or female adult parents were subjected to laser radiation.

  6. An evaluation of the effectiveness of a commercial mechanical trap to reduce abundance of adult nuisance mosquito populations.

    PubMed

    Jackson, Michael J; Gow, Jennifer L; Evelyn, Michelle J; McMahon, T J Scott; Howay, Tim J; Campbell, Harlan; Blancard, Jennifer; Thielman, Aynsley

    2012-12-01

    In this study, we explore the potential of a commercially available mechanical mosquito control device, the Liberty Plus Mosquito Magnet (hereafter referred to as Mosquito Magnet), to reduce the abundance of adult nuisance mosquito populations in public recreational areas. Mosquitoes were trapped on 2 replicate sites close to a campground at Brae Island Regional Park near Fort Langley, British Columbia, Canada. Each site comprised a treatment (Mosquito Magnets used) and control subsection (Mosquito Magnets not used). Mosquito numbers were assessed before and after the treatment period in both subsections at each site with Centers for Disease Control and Prevention (CDC) black light traps. Although nearly 200,000 mosquitoes from 14 different species were collected over 366 trap-nights from May 31 to July 31, 2008, the majority of those identified were Aedes sticticus (68%) and Ae. vexans (22%)-2 of the most notorious nuisance mosquito species in British Columbia. The number of mosquitoes captured by CDC black light traps increased overall during the study period due to natural seasonal variation. Nevertheless, a significant treatment effect (P = 0.0389) was associated with an average decrease of about 32% in the average number of adult mosquitoes collected per day. These results strongly suggest that Mosquito Magnets can reduce the abundance of nuisance mosquitoes, potentially reducing the biting pressure on the public, and providing another tool in mosquito control operations.

  7. Mosquito, adult (image)

    MedlinePlus

    This illustration shows an adult southern house mosquito. This mosquito feeds on blood and is the carrier of many diseases, such as encephalitis, West Nile, dengue fever, yellow fever, and others. ( ...

  8. Meteorological effects on adult mosquito (Culex) populations in metropolitan New Jersey.

    PubMed

    Degaetano, Arthur T

    2005-05-01

    For two metropolitan New Jersey counties, monthly average adult mosquito (Culex) catch from New Jersey light trap data sets covering multiple decades is related to a number of meteorological factors. From June through August climatological conditions accounted for between 40% and 50% of the variation in average catch. In general, high monthly precipitation totals both in the month corresponding to the catch and the previous month were associated with increased trap catch. However, individual heavy rainfall events tended to reduce catch. Warm temperatures exerted a positive influence on mosquito abundance in June, but were associated with a low catch in August. Linear meteorological relationships explained only a small percentage of the variations in mosquito catch during May and September. During July, and particularly August, antecedent monthly catch also explained a significant portion of the variance in the contemporaneous catch. Over 60% of the variability in August catch could be attributed to the July population.

  9. Thorsellia anophelis is the dominant bacterium in a Kenyan population of adult Anopheles gambiae mosquitoes.

    PubMed

    Briones, Aurelio M; Shililu, Josephat; Githure, John; Novak, Robert; Raskin, Lutgarde

    2008-01-01

    Anopheles gambiae mosquitoes are not known to harbor endosymbiotic bacteria. Here we show, using nucleic acid-based methods, that 16S rRNA gene sequences specific to a recently described mosquito midgut bacterium, Thorsellia anophelis, is predominant in the midgut of adult An. gambiae s.l. mosquitoes captured in residences in central Kenya, and also occurs in the aquatic rice paddy environment nearby. PCR consistently detected T. anophelis in the surface microlayer of rice paddies, which is also consistent with the surface-feeding behavior of A. gambiae s.l. larvae. Phylogenetic analysis of cloned environmental 16S rRNA genes identified four major Thorsellia lineages, which are closely affiliated to an insect endosymbiont of the genus Arsenophonus. Physiological characterizations support the hypothesis that T. anophelis is well adapted to the female anopheline midgut by utilizing blood and tolerating the alkaline conditions in this environment. The results suggest that aquatically derived bacteria such as T. anophelis can persist through mosquito metamorphosis and become well-established in the adult mosquito midgut.

  10. Mosquito populations dynamics associated with climate variations.

    PubMed

    Wilke, André Barretto Bruno; Medeiros-Sousa, Antônio Ralph; Ceretti-Junior, Walter; Marrelli, Mauro Toledo

    2017-02-01

    Mosquitoes are responsible for the transmission of numerous serious pathogens. Members of the Aedes and Culex genera, which include many important vectors of mosquito-borne diseases, are highly invasive and adapted to man-made environments. They are spread around the world involuntarily by humans and are highly adapted to urbanized environments, where they are exposed to climate-related abundance drivers. We investigated Culicidae fauna in two urban parks in the city of São Paulo to analyze the correlations between climatic variables and the population dynamics of mosquitoes in these urban areas. Mosquitoes were collected monthly over one year, and sampling sufficiency was evaluated after morphological identification of the specimens. The average monthly temperature and accumulated rainfall for the collection month and previous month were used to explain climate-related abundance drivers for the six most abundant species (Aedes aegypti, Aedes albopictus, Aedes fluviatilis, Aedes scapularis, Culex nigripalpus and Culex quinquefasciatus) and then analyzed using generalized linear statistical models and the Akaike Information Criteria corrected for small samples (AICc). The strength of evidence in favor of each model was evaluated using Akaike weights, and the explanatory model power was measured by McFadden's Pseudo-R(2). Associations between climate and mosquito abundance were found in both parks, indicating that predictive models based on climate variables can provide important information on mosquito population dynamics. We also found that this association is species-dependent. Urbanization processes increase the abundance of a few mosquito species that are well adapted to man-made environments and some of which are important vectors of pathogens. Predictive models for abundance based on climate variables may help elucidate the population dynamics of urban mosquitoes and their impact on the risk of disease transmission, allowing better predictive scenarios to be

  11. Effect of sampling method on the species composition and abundance of adult mosquitoes in a Florida swamp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Samples of the adult mosquito populations in a Florida swamp (Sumter Co.) were obtained using suction traps and portable CDC light traps (augmented with CO2) and the results compared with mosquitoes captured by mechanical aspirator when landing on a human subject. Sixteen mosquito species total wer...

  12. The Role of Mosquitoes in the Diet of Adult Dragon and Damselflies (Odonata).

    PubMed

    Pfitzner, Wolf Peter; Beck, Matthias; Weitzel, Thomas; Becker, Norbert

    2015-06-01

    The flood plains of the Upper Rhine Valley provide excellent conditions for the proliferation of mosquitoes as well as for the development of dragon and damselflies. It could be assumed that mosquitoes belong to the diet of the Odonata and that the latter could be harmed by the reduction of the mosquito population with the purpose of diminishing the massive nuisance for the people living there. A total of 41 adult dragonflies and damselflies were examined by immunoblot for remnants of mosquitoes in their guts. A rabbit antiserum against Aedes vexans proteins was used for the immunoblot. Only 3 Aeshna cyanea and 1 Platycnemis pennipes could be shown to have fed on mosquitoes. In specimens of the genus Sympetrum no mosquitoes were detected. It seems very doubtful that mosquitoes are an essential part of the Odonata diet.

  13. Evaluation of a Stable Isotope Method to Mark Naturally-Breeding Larval Mosquitoes for Adult Dispersal Studies

    PubMed Central

    HAMER, GABRIEL L.; DONOVAN, DANIELLE J.; HOOD-NOWOTNY, REBECCA; KAUFMAN, MICHAEL G.; GOLDBERG, TONY L.; WALKER, EDWARD D.

    2014-01-01

    Understanding mosquito dispersal is critically important for vector-borne disease control and prevention. Mark–release–recapture methods using various marking techniques have made substantial contributions to the study of mosquito biology. However, the ability to mark naturally breeding mosquitoes noninvasively and with life-long retention has remained problematic. Here, we describe a method to mark naturally breeding mosquitoes with stable isotopes. Culexpipiens f. molestus mosquitoes were provisioned as larvae in laboratory experiments with 15N-labeled potassium nitrate and 13C-labeled glucose. Larval enrichment was sufficient to differentiate marked adult mosquitoes from unmarked control mosquitoes and the natural source population from Chicago Illinois, using either δ15N or δ13C. Isotopic retention lasted for at least 55 d for adult male and females mosquitoes. There were no consistent effects of isotopic enrichment on immature mosquito survival or adult mosquito body size. We then applied this marking technique to naturally breeding Culex pipiens mosquitoes in suburban Chicago, IL, and for the first time, report successful isotopic enrichment of mosquitoes in the field. This stable isotope marking technique will facilitate studies of mosquito dispersal. PMID:22308772

  14. Bacterial associations reveal spatial population dynamics in Anopheles gambiae mosquitoes

    PubMed Central

    Buck, Moritz; Nilsson, Louise K. J.; Brunius, Carl; Dabiré, Roch K.; Hopkins, Richard; Terenius, Olle

    2016-01-01

    The intolerable burden of malaria has for too long plagued humanity and the prospect of eradicating malaria is an optimistic, but reachable, target in the 21st century. However, extensive knowledge is needed about the spatial structure of mosquito populations in order to develop effective interventions against malaria transmission. We hypothesized that the microbiota associated with a mosquito reflects acquisition of bacteria in different environments. By analyzing the whole-body bacterial flora of An. gambiae mosquitoes from Burkina Faso by 16 S amplicon sequencing, we found that the different environments gave each mosquito a specific bacterial profile. In addition, the bacterial profiles provided precise and predicting information on the spatial dynamics of the mosquito population as a whole and showed that the mosquitoes formed clear local populations within a meta-population network. We believe that using microbiotas as proxies for population structures will greatly aid improving the performance of vector interventions around the world. PMID:26960555

  15. The importance of temperature fluctuations in understanding mosquito population dynamics and malaria risk

    PubMed Central

    Nelson, William A.; Paaijmans, Krijn P.; Thomas, Matthew B.; Bjørnstad, Ottar N.

    2017-01-01

    Temperature is a key environmental driver of Anopheles mosquito population dynamics; understanding its central role is important for these malaria vectors. Mosquito population responses to temperature fluctuations, though important across the life history, are poorly understood at a population level. We used stage-structured, temperature-dependent delay-differential equations to conduct a detailed exploration of the impacts of diurnal and annual temperature fluctuations on mosquito population dynamics. The model allows exploration of temperature-driven temporal changes in adult age structure, giving insights into the population’s capacity to vector malaria parasites. Because of temperature-dependent shifts in age structure, the abundance of potentially infectious mosquitoes varies temporally, and does not necessarily mirror the dynamics of the total adult population. In addition to conducting the first comprehensive theoretical exploration of fluctuating temperatures on mosquito population dynamics, we analysed observed temperatures at four locations in Africa covering a range of environmental conditions. We found both temperature and precipitation are needed to explain the observed malaria season in these locations, enhancing our understanding of the drivers of malaria seasonality and how temporal disease risk may shift in response to temperature changes. This approach, tracking both mosquito abundance and age structure, may be a powerful tool for understanding current and future malaria risk.

  16. Mosquito, adult feeding on the skin (image)

    MedlinePlus

    There are many different species of mosquito, which can carry some of the world's most common and significant infectious diseases, including West Nile, Malaria, yellow fever, viral encephalitis, and ...

  17. Effects of rainfall on Culex mosquito population dynamics.

    PubMed

    Valdez, L D; Sibona, G J; Diaz, L A; Contigiani, M S; Condat, C A

    2017-03-27

    The dynamics of a mosquito population depends heavily on climatic variables such as temperature and precipitation. Since climate change models predict that global warming will impact on the frequency and intensity of rainfall, it is important to understand how these variables affect the mosquito populations. We present a model of the dynamics of a Culex quinquefasciatus mosquito population that incorporates the effect of rainfall and use it to study the influence of the number of rainy days and the mean monthly precipitation on the maximum yearly abundance of mosquitoes Mmax. Additionally, using a fracturing process, we investigate the influence of the variability in daily rainfall on Mmax. We find that, given a constant value of monthly precipitation, there is an optimum number of rainy days for which Mmax is a maximum. On the other hand, we show that increasing daily rainfall variability reduces the dependence of Mmax on the number of rainy days, leading also to a higher abundance of mosquitoes for the case of low mean monthly precipitation. Finally, we explore the effect of the rainfall in the months preceding the wettest season, and we obtain that a regimen with high precipitations throughout the year and a higher variability tends to advance slightly the time at which the peak mosquito abundance occurs, but could significantly change the total mosquito abundance in a year.

  18. Comparative estimates of density and species diversity in adult mosquito populations landing on a human subject and captured using light and suction traps.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Comparative responses of 21 species of mosquitoes to light traps (LT) and suction traps (ST) and captured using the human landing collection method (HL) varied in accordance with collection technique but data analyses for most species revealed significant interaction between collection method and th...

  19. Sampling of adult mosquito vectors with Mosquito Magnet Pro in Panaji, Goa, India.

    PubMed

    Korgaonkar, Nandini S; Kumar, Ashwani; Yadav, Rajpal S; Kabadi, Dipak; Dash, Aditya P

    2008-12-01

    For mosquito vector population monitoring, a new commercial trap, Mosquito Magnet Pro (MM-PRO), was tested for its usefulness in Goa, India. Anopheles stephensi was tested for the presence of Plasmodium sporozoite infection in the salivary glands. Using the MM-PRO 24 h a day for 34 days, 2,329 mosquitoes belonging to 16 species were collected. These included 6 species each of the genera Anopheles and Culex, 2 species of Aedes, and 1 each of Mansonia and Armigeres. Most (91%) of the mosquitoes caught were females. Among these the number and percentage of each species were Anopheles stephensi 59 (2.78%), Culex quinquefasciatus 1013 (47.78%), Culex vishnui 551 (26.0%), Mansonia uniformis 216 (10.19%), and Aedes albopictus 1 (0.04%). Of the 54 An. stephensi females tested for the presence of circumsporozoite protein (CSP) by an ELISA technique, 1 was found to be Plasmodium falciparum CSP positive. The MM-PRO device was found useful for mosquito population sampling in the urban setting of Goa.

  20. Controlling Mosquitoes at the Larval Stage

    EPA Pesticide Factsheets

    Larvicides target larvae in the breeding habitat before they can mature into adult mosquitoes and disperse. Larvicide treatment of breeding habitats help reduce the adult mosquito population in nearby areas.

  1. Control of vector populations using genetically modified mosquitoes.

    PubMed

    Wilke, André Barreto Bruno; Gomes, Almério de Castro; Natal, Delsio; Marrelli, Mauro Toledo

    2009-10-01

    The ineffectiveness of current strategies for chemical control of mosquito vectors raises the need for developing novel approaches. Thus, we carried out a literature review of strategies for genetic control of mosquito populations based on the sterile insect technique. One of these strategies consists of releasing radiation-sterilized males into the population; another, of integrating a dominant lethal gene under the control of a specific promoter into immature females. Advantages of these approaches over other biological and chemical control strategies include: highly species-specific, environmentally safety, low production cost, and high efficacy. The use of this genetic modification technique will constitute an important tool for integrated vector management.

  2. European Surveillance for West Nile Virus in Mosquito Populations

    PubMed Central

    Engler, Olivier; Savini, Giovanni; Papa, Anna; Figuerola, Jordi; Groschup, Martin H.; Kampen, Helge; Medlock, Jolyon; Vaux, Alexander; Wilson, Anthony J.; Werner, Doreen; Jöst, Hanna; Goffredo, Maria; Capelli, Gioia; Federici, Valentina; Tonolla, Mauro; Patocchi, Nicola; Flacio, Eleonora; Portmann, Jasmine; Rossi-Pedruzzi, Anya; Mourelatos, Spiros; Ruiz, Santiago; Vázquez, Ana; Calzolari, Mattia; Bonilauri, Paolo; Dottori, Michele; Schaffner, Francis; Mathis, Alexander; Johnson, Nicholas

    2013-01-01

    A wide range of arthropod-borne viruses threaten both human and animal health either through their presence in Europe or through risk of introduction. Prominent among these is West Nile virus (WNV), primarily an avian virus, which has caused multiple outbreaks associated with human and equine mortality. Endemic outbreaks of West Nile fever have been reported in Italy, Greece, France, Romania, Hungary, Russia and Spain, with further spread expected. Most outbreaks in Western Europe have been due to infection with WNV Lineage 1. In Eastern Europe WNV Lineage 2 has been responsible for human and bird mortality, particularly in Greece, which has experienced extensive outbreaks over three consecutive years. Italy has experienced co-circulation with both virus lineages. The ability to manage this threat in a cost-effective way is dependent on early detection. Targeted surveillance for pathogens within mosquito populations offers the ability to detect viruses prior to their emergence in livestock, equine species or human populations. In addition, it can establish a baseline of mosquito-borne virus activity and allow monitoring of change to this over time. Early detection offers the opportunity to raise disease awareness, initiate vector control and preventative vaccination, now available for horses, and encourage personal protection against mosquito bites. This would have major benefits through financial savings and reduction in equid morbidity/mortality. However, effective surveillance that predicts virus outbreaks is challenged by a range of factors including limited resources, variation in mosquito capture rates (too few or too many), difficulties in mosquito identification, often reliant on specialist entomologists, and the sensitive, rapid detection of viruses in mosquito pools. Surveillance for WNV and other arboviruses within mosquito populations varies between European countries in the extent and focus of the surveillance. This study reviews the current status of

  3. Linking movement and oviposition behaviour to spatial population distribution in the tree hole mosquito Ochlerotatus triseriatus.

    PubMed

    Ellis, Alicia M

    2008-01-01

    1. Researchers often use the spatial distribution of insect offspring as a measure of adult oviposition preferences, and then make conclusions about the consequences of these preferences for population growth and the relationship between life-history traits (e.g. oviposition preference and offspring performance). However, several processes other than oviposition preference can generate spatial patterns of offspring density (e.g. dispersal limitations, spatially heterogeneous mortality rates). Incorrectly assuming that offspring distributions reflect oviposition preferences may therefore compromise our ability to understand the mechanisms determining population distributions and the relationship between life-history traits. 2. The purpose of this study was to perform an empirical study at the whole-system scale to examine the movement and oviposition behaviours of the eastern tree hole mosquito Ochlerotatus triseriatus (Say) and test the importance of these behaviours in determining population distribution relative to other mechanisms. 3. A mark-release-recapture experiment was performed to distinguish among the following alternative hypotheses that may explain a previously observed aggregated distribution of tree hole mosquito offspring: (H(1)) mosquitoes prefer habitats with particular vegetation characteristics and these preferences determine the distribution of their offspring; (H(2)) mosquitoes distribute their eggs randomly or evenly throughout their environment, but spatial differences in developmental success generate an aggregated pattern of larval density; (H(3)) mosquitoes randomly colonize habitats, but have limited dispersal capability causing them to distribute offspring where founder populations were established; (H(4)) wind or other environmental factors may lead to passive aggregation, or spatial heterogeneity in adult mortality (H(5)), rather than dispersal, generates clumped offspring distributions. 4. Results indicate that the distribution of

  4. Controlling malaria: competition, seasonality and 'slingshotting' transgenic mosquitoes into natural populations.

    PubMed

    Schaffer, W M; Bronnikova, T V

    2009-03-01

    Forty years after the World Health Organization abandoned its eradication campaign, malaria remains a public health problem of the first magnitude with worldwide infection rates on the order of 300 million souls. The present paper reviews potential control strategies from the viewpoint of mathematical epidemiology. Following MacDonald and others, we argue in Section 1 that the use of imagicides, i.e., killing, or at least repelling, adult mosquitoes, is inherently the most effective way of combating the pandemic. In Section 2, we model competition between wild-type (WT) and plasmodium-resistant, genetically modified (GM) mosquitoes. Under the assumptions of inherent cost and prevalence-dependant benefit to transgenics, GM introduction can never eradicate malaria save by stochastic extinction of WTs. Moreover, alternative interventions that reduce prevalence have the undesirable consequence of reducing the likelihood of successful GM introduction. Section 3 considers the possibility of using seasonal fluctuations in mosquito abundance and disease prevalence to 'slingshot' GM mosquitoes into natural populations. By introducing GM mosquitoes when natural populations are about to expand, one can 'piggyback' on the yearly cycle. Importantly, this effect is only significant when transgene cost is small, in which case the non-trivial equilibrium is a focus (damped oscillations), and piggybacking is amplified by the system's inherent tendency to oscillate. By way of contrast, when transgene cost is large, the equilibrium is a node and no such amplification is obtained.

  5. Using adult mosquitoes to transfer insecticides to Aedes aegypti larval habitats.

    PubMed

    Devine, Gregor J; Perea, Elvira Zamora; Killeen, Gerry F; Stancil, Jeffrey D; Clark, Suzanne J; Morrison, Amy C

    2009-07-14

    Vector control is a key means of combating mosquito-borne diseases and the only tool available for tackling the transmission of dengue, a disease for which no vaccine, prophylaxis, or therapeutant currently exists. The most effective mosquito control methods include a variety of insecticidal tools that target adults or juveniles. Their successful implementation depends on impacting the largest proportion of the vector population possible. We demonstrate a control strategy that dramatically improves the efficiency with which high coverage of aquatic mosquito habitats can be achieved. The method exploits adult mosquitoes as vehicles of insecticide transfer by harnessing their fundamental behaviors to disseminate a juvenile hormone analogue (JHA) between resting and oviposition sites. A series of field trials undertaken in an Amazon city (Iquitos, Peru) showed that the placement of JHA dissemination stations in just 3-5% of the available resting area resulted in almost complete coverage of sentinel aquatic habitats. More than control mortality occurred in 95-100% of the larval cohorts of Aedes aegypti developing at those sites. Overall reductions in adult emergence of 42-98% were achieved during the trials. A deterministic simulation model predicts amplifications in coverage consistent with our observations and highlights the importance of the residual activity of the insecticide for this technique.

  6. Biodistribution and Trafficking of Hydrogel Nanoparticles in Adult Mosquitoes

    PubMed Central

    Paquette, Cynthia C. H.; Phanse, Yashdeep; Perry, Jillian L.; Sanchez-Vargas, Irma; Airs, Paul M.; Dunphy, Brendan M.; Xu, Jing; Carlson, Jonathan O.; Luft, J. Christopher; DeSimone, Joseph M.; Bartholomay, Lyric C.; Beaty, Barry J.

    2015-01-01

    Background Nanotechnology offers great potential for molecular genetic investigations and potential control of medically important arthropods. Major advances have been made in mammalian systems to define nanoparticle (NP) characteristics that condition trafficking and biodistribution of NPs in the host. Such information is critical for effective delivery of therapeutics and molecules to cells and organs, but little is known about biodistribution of NPs in mosquitoes. Methodology/Principal Findings PRINT technology was used to construct a library of fluorescently labeled hydrogel NPs of defined size, shape, and surface charge. The biodistribution (organ, tissue, and cell tropisms and trafficking kinetics) of positively and negatively charged 200 nm x 200 nm, 80 nm x 320 nm, and 80 nm x 5000 nm NPs was determined in adult Anopheles gambiae mosquitoes as a function of the route of challenge (ingestion, injection or contact) using whole body imaging and fluorescence microscopy. Mosquitoes readily ingested NPs in sugar solution. Whole body fluorescence imaging revealed substantial NP accumulation (load) in the alimentary tracts of the adult mosquitoes, with the greatest loads in the diverticula, cardia and foregut. Positively and negatively charged NPs differed in their biodistribution and trafficking. Following oral challenge, negatively charged NPs transited the alimentary tract more rapidly than positively charged NPs. Following contact challenge, negatively charged NPs trafficked more efficiently in alimentary tract tissues. Following parenteral challenge, positively and negatively charged NPs differed in tissue tropisms and trafficking in the hemocoel. Injected NPs were also detected in cardia/foregut, suggesting trafficking of NPs from the hemocoel into the alimentary tract. Conclusions/Significance Herein we have developed a tool box of NPs with the biodistribution and tissue tropism characteristics for gene structure/function studies and for delivery of vector

  7. Effects of intraspecific larval competition on adult longevity in the mosquitoes Aedes aegypti and Aedes albopictus

    PubMed Central

    LOUNIBOS, L. P.

    2009-01-01

    Larval competition is common in container-breeding mosquitoes. The impact of competition on larval growth has been thoroughly examined and findings that larval competition can lead to density-dependent effects on adult body size have been documented. The effects of larval competition on adult longevity have been less well explored. The effects of intraspecific larval densities on the longevity of adults maintained under relatively harsh environmental conditions were tested in the laboratory by measuring the longevity of adult Aedes aegypti (L.) and Aedes albopictus (Skuse) (Diptera: Culicidae) that had been reared under a range of larval densities and subsequently maintained in high- or low-humidity regimes (85% or 35% relative humidity [RH], respectively) as adults. We found significant negative effects of competition on adult longevity in Ae. aegypti, but not in Ae. albopictus. Multivariate analysis of variance suggested that the negative effect of the larval environment on the longevity of Ae. aegypti adults was most strongly associated with increased development time and decreased wing length as adults. Understanding how larval competition affects adult longevity under a range of environmental conditions is important in establishing the relationship between models of mosquito population regulation and epidemiological models of vector-borne disease transmission. PMID:19239615

  8. Population structure of the peridomestic mosquito Ochlerotatus notoscriptus in Australia.

    PubMed

    Foley, D H; Russell, R C; Bryan, J H

    2004-06-01

    Ochlerotatus notoscriptus (Skuse) (Diptera: Culicidae) is the predominant peridomestic mosquito in Australia where it is the primary vector of dog heartworm, Dirofilaria immitis (Leidy), and a potentially important vector of arboviruses (Barmah Forest, Ross River) with geographical variation of vector competence. Although widespread, Oc. notoscriptus has low dispersal ability, so it may have isolated subpopulations. The identification of gene flow barriers may assist in understanding arbovirus epidemiology and disease risk, and for developing control strategies for this species. We investigated the population structure of Oc. notoscriptus from 17 sites around Australia, using up to 31 putative allozyme loci, 11 of which were polymorphic. We investigated the effect of larval environment and adult morphology on genetic variation. At least five subpopulations were found, four in New South Wales (NSW) and one unique to Darwin. Perth samples appear to be a product of recent colonization from the Australian east coast. For NSW sites, a Mantel test revealed an isolation by distance effect and spatial autocorrelation analysis revealed an area of effective gene flow of 67 km, which is high given the limited dispersal ability of this species. No consistent difference was observed between 'urban' and 'sylvan' habitats, which suggests frequent movement between these sites. However, a finer-scaled habitat study at Darwin revealed small but significant allele frequency differences, including for Gpi. No fixed allozyme differences were detected for sex, size, integument colour or the colour of species-diagnostic pale scales on the scutum. The domestic habit of Oc. notoscriptus and assisted dispersal have helped to homogenize this species geographically but population structure is still detectable on several levels associated with geographical variation of vector competence.

  9. Seasonal population density and daily survival of anopheline mosquitoes (Diptera: Culicidae) in a malaria endemic area, Republic of Korea.

    PubMed

    Shin, E-Hyun; Lee, Won-Ja; Lee, Hee Il; Lee, Dong-Kyu; Klein, Terry A

    2005-06-01

    Mosquito surveillance was conducted near the Korean Demilitarized Zone (Paju County, Gyeonggi Province) from April to October, 1999, where malaria cases were reported. Adult mosquito surveillance, using black light and CDC UV light traps, was conducted at five and two sites, respectively. Weekly larval collections were made at five rice paddies located adjacent to the adult collection sites. Anopheles sinensis was the most abundant mosquito of 11 species collected throughout the surveillance period in 1999, comprising 47 - 48% of the total number of mosquitoes collected at cow sheds and residence. At all five sites surveyed by CDC UV light traps, anophelines appeared early in the year (May 3) and were most abundant in the cow sheds followed by the hillside forest, residence, stream/river bank, and were least abundant in rice fields. The population density of the larvae and the adults of An. sinensis increased steadily in June and reached their peaks during the second week of July (mean 112 females/trap/night). The parity rates were higher in July and September, when populations were highest. The probabilities of daily survival of An. sinensis were 0.804 in June to 0.895 in July. Cross-correlation showed a significant relationship between the number of adult anopheline mosquitoes and the number of larvae collected on the previous day, the same day, and also three and seven days later, which may be useful for determining treatment thresholds.

  10. A study of population changes in adult Culex quinquefasciatus Say (Diptera: Culicidae) during a mosquito control programme in Dubai, United Arab Emirates.

    PubMed

    Holmes, P R

    1986-02-01

    The effectiveness of insecticidal control measures on adult Culex quinquefasciatus Say in Dubai, United Arab Emirates, was examined. Direct treatment of the study site with cypermethrin applied as a fog caused a temporary reduction both in total numbers (males and females) and in the proportion of older females. When cypermethrin was applied as an ultra low volume formulation at dusk and dawn numbers of males were greatly reduced, but numbers of females were not affected. It appears that the adulticiding operations had little overall effect on the total numbers or survival rate of females, or breeding success. The oviposition cycle duration was estimated to be two days, with the survival rate per oviposition cycle calculated as 30%. With these values it is thought unlikely that filariasis would be transmitted in Dubai.

  11. Mosquito population dynamic (Diptera: Culicidae) in a eutrophised dam.

    PubMed

    Wermelinger, E D; Benigno, C V; Machado, R N M; Cabello, P H; Meira, A M; Ferreira, A P; Zanuncio, J C

    2012-11-01

    This study observed the mosquito population in a rural eutrophised dam. Larvae of L3 and L4 stages and pupae were dipped out during twelve month collections and the reared to the adult stage for identification. The collections were done along nine metres from the edge of the dam divided in three parts (P1, P2 and P3), each part being 3 m long. P1 did not have vegetation (grass) along its edge,which would reach or sink into the water to promote some shade on the marginal water. A total of 217 adults of four species was identified with the following constancies and frequencies: Culex quinquefasciatus (Say, 1823) (83% and 40.6%), Anopheles (Nyssorhynchus) evansae (Brèthes, 1926) (92% and 26.7%), Anopheles (Nyssorhynchus) rangeli (Gabaldon, Cova Garcia and Lopez, 1940) (83% and 14.3%) and Culex nigripalpus (Theobald, 1901) (33% and 18.4%). C. quinquefasciatus, A. evansae, A. rangeli and C. nigripalpus were more frequent in the quarters Nov./Dec./Jan. (85.7%), May/June/July (75%), Aug./Sept./Oct. (29.4%) and Aug./Sept./Oct. (23.5%) particularly in the months of December (88.4%) Sept.tember (48.94), (38.3) and August (47.62) respectively. The presence of C. quinquefasciatus and the high incidence of Daphinia sp. and also the levels of Organic Nitrogen (0.28 mg/L) and of total Phosphorus (0.02 mg/L) are indications of the eutrophication of the dam. There was a difference regarding the total of Anopheles (A. avansae + A. rangeli) and Culex species (C. quinquefasciatus + C. nigripalpis) between P1 and P2 (χ(2) = 0.0097), P1 and P3 (χ(2) = 0.0005), but not between P2 and P3 (χ(2) = 0.2045).The high C. quinquefasciatus constancy and frequency were confirmed to be a good biological indicator for a eutrophised environment and A. evansae showed a good potential for this environment. Vegetation can be an important factor for anopheline population dynamic also in eutrophic breeding sites.

  12. Midgut Microbial Community of Culex quinquefasciatus Mosquito Populations from India

    PubMed Central

    Chandel, Kshitij; Mendki, Murlidhar J.; Parikh, Rasesh Y.; Kulkarni, Girish; Tikar, Sachin N.; Sukumaran, Devanathan; Prakash, Shri; Parashar, Brahma D.; Shouche, Yogesh S.; Veer, Vijay

    2013-01-01

    The mosquito Culex quinquefasciatus is a ubiquitous species that serves as a major vector for west nile virus and lymphatic filariasis. Ingestion of bloodmeal by females triggers a series of physiological processes in the midgut and also exposes them to infection by these pathogens. The bacteria normally harbored in the midgut are known to influence physiology and can also alter the response to various pathogens. The midgut bacteria in female Cx. quinquefasciatus mosquitoes collected over a large geographical area from India was studied. Examination of 16S ribosomal DNA amplicons from culturable microflora revealed the presence of 83 bacterial species belonging to 31 bacterial genera. All of these species belong to three phyla i.e. Proteobacteria, Firmicutes and Actinobacteria. Phylum Proteobacteria was the most dominant phylum (37 species), followed by Firmicutes (33 species) and Actinobacteria (13 species). Phylum Proteobacteria, was dominated by members of γ-proteobacteria class. The genus Staphylococcus was the largest genus represented by 11 species whereas Enterobacter was the most prevalent genus and recovered from all the field stations except Leh. Highest bacterial prevalence was observed from Bhuj (22 species) followed by Nagrota (18 species), Masimpur (18 species) and Hathigarh (16 species). Whereas, least species were observed from Leh (8 species). It has been observed that individual mosquito harbor extremely diverse gut bacteria and have very small overlap bacterial taxa in their gut. This variation in midgut microbiota may be one of the factors responsible for variation in disease transmission rates or vector competence within mosquito population. The present data strongly encourage further investigations to verify the potential role of the detected bacteria in mosquito for the transmission of lymphatic filariasis and west nile virus. To the best of our knowledge this is the first study on midgut microbiota of wild Cx. quinquefasciatus from over a

  13. Mosquito population dynamics from cellular automata-based simulation

    NASA Astrophysics Data System (ADS)

    Syafarina, Inna; Sadikin, Rifki; Nuraini, Nuning

    2016-02-01

    In this paper we present an innovative model for simulating mosquito-vector population dynamics. The simulation consist of two stages: demography and dispersal dynamics. For demography simulation, we follow the existing model for modeling a mosquito life cycles. Moreover, we use cellular automata-based model for simulating dispersal of the vector. In simulation, each individual vector is able to move to other grid based on a random walk. Our model is also capable to represent immunity factor for each grid. We simulate the model to evaluate its correctness. Based on the simulations, we can conclude that our model is correct. However, our model need to be improved to find a realistic parameters to match real data.

  14. Female Adult Aedes albopictus Suppression by Wolbachia-Infected Male Mosquitoes

    PubMed Central

    Mains, James W.; Brelsfoard, Corey L.; Rose, Robert I.; Dobson, Stephen L.

    2016-01-01

    Dengue, chikungunya and zika viruses are pathogens with an increasing global impact. In the absence of an approved vaccine or therapy, their management relies on controlling the mosquito vectors. But traditional controls are inadequate, and the range of invasive species such as Aedes albopictus (Asian Tiger Mosquito) is expanding. Genetically modified mosquitoes are being tested, but their use has encountered regulatory barriers and public opposition in some countries. Wolbachia bacteria can cause a form of conditional sterility, which can provide an alternative to genetic modification or irradiation. It is unknown however, whether openly released, artificially infected male Ae. albopictus can competitively mate and sterilize females at a level adequate to suppress a field population. Also, the unintended establishment of Wolbachia at the introduction site could result from horizontal transmission or inadvertent female release. In 2014, an Experimental Use Permit from the United States Environmental Protection Agency approved a pilot field trial in Lexington, Kentucky, USA. Here, we present data showing localized reduction of both egg hatch and adult female numbers. The artificial Wolbachia type was not observed to establish in the field. The results are discussed in relation to the applied use of Wolbachia-infected males as a biopesticide to suppress field populations of Ae. albopictus. PMID:27659038

  15. Susceptibility of Adult Mosquitoes to Insecticides in Aqueous Sucrose Baits

    DTIC Science & Technology

    2011-06-01

    2010 ABSTRACT: Mosquitoes characteristically feed on plant-derived carbohydrates and honeydew just after emergence and intermittently during their...bait, Culex, Aedes, Anopheles. INTRODUCTION Plant-derived sugars and honeydew provide important components of mosquito nutrition and contribute to...unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Mosquitoes characteristically feed on plant-derived carbohydrates and honeydew just after emergence

  16. Effect of collection method on estimates of adult mosquito density

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We made simultaneous comparison of the number of female mosquitoes captured by suction traps and portable light traps (augmented with CO2) in a Florida swamp with the landing rate of female mosquitoes on a human subject. Depending on the mosquito species, capture rates in light traps ranged between...

  17. Adult survivorship of the dengue mosquito Aedes aegypti varies seasonally in central Vietnam.

    PubMed

    Hugo, Leon E; Jeffery, Jason A L; Trewin, Brendan J; Wockner, Leesa F; Nguyen, Thi Yen; Nguyen, Hoang Le; Nghia, Le Trung; Hine, Emma; Ryan, Peter A; Kay, Brian H

    2014-02-01

    The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop) that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April) and dry/hot (May-August) seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d), respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle.

  18. Larval food quantity affects the capacity of adult mosquitoes to transmit human malaria

    PubMed Central

    Shapiro, Lillian L. M.; Murdock, Courtney C.; Jacobs, Gregory R.; Thomas, Rachel J.; Thomas, Matthew B.

    2016-01-01

    Adult traits of holometabolous insects are shaped by conditions experienced during larval development, which might impact interactions between adult insect hosts and parasites. However, the ecology of larval insects that vector disease remains poorly understood. Here, we used Anopheles stephensi mosquitoes and the human malaria parasite Plasmodium falciparum, to investigate whether larval conditions affect the capacity of adult mosquitoes to transmit malaria. We reared larvae in two groups; one group received a standard laboratory rearing diet, whereas the other received a reduced diet. Emerging adult females were then provided an infectious blood meal. We assessed mosquito longevity, parasite development rate and prevalence of infectious mosquitoes over time. Reduced larval food led to increased adult mortality and caused a delay in parasite development and a slowing in the rate at which parasites invaded the mosquito salivary glands, extending the time it took for mosquitoes to become infectious. Together, these effects increased transmission potential of mosquitoes in the high food regime by 260–330%. Such effects have not, to our knowledge, been shown previously for human malaria and highlight the importance of improving knowledge of larval ecology to better understand vector-borne disease transmission dynamics. PMID:27412284

  19. Reproductive phase locking of mosquito populations in response to rainfall frequency.

    PubMed

    Shaman, Jeffrey; Day, Jonathan F

    2007-03-28

    The frequency of moderate to heavy rainfall events is projected to change in response to global warming. Here we show that these hydrologic changes may have a profound effect on mosquito population dynamics and rates of mosquito-borne disease transmission. We develop a simple model, which treats the mosquito reproductive cycle as a phase oscillator that responds to rainfall frequency forcing. This model reproduces observed mosquito population dynamics and indicates that mosquito-borne disease transmission can be sensitive to rainfall frequency. These findings indicate that changes to the hydrologic cycle, in particular the frequency of moderate to heavy rainfall events, could have a profound effect on the transmission rates of some mosquito-borne diseases.

  20. Impact of dryland salinity on population dynamics of vector mosquitoes (Diptera: Culicidae) of Ross River virus in inland areas of southwestern Western Australia.

    PubMed

    Jardine, A; Lindsay, M D A; Johansen, C A; Cook, A; Weinstein, P

    2008-11-01

    Clearing of native vegetation for agriculture since European settlement has left 1.047 million ha of southwestern Australia affected by a severe form of environmental degradation called dryland salinity, characterized by secondary soil salinization and waterlogging. This area may expand by a further 1.7-3.4 million ha if current trends continue. Detailed investigations of seasonal of adult and larval mosquito population dynamics were undertaken in the region to test the hypothesis that the development of dryland salinity and waterlogging in inland southwestern Australia has led to a succession of mosquito species and increased Ross River virus (family Togaviridae, genus Alphavirus, RRV) transmission risk. Aedes (Ochlerotatus) camptorhynchus (Thomson) made up >90% of adult mosquito collections in saline regions. Nonmetric multidimensional scaling and generalized estimating equations modeling demonstrated that it was strongly associated with increasing severity of dryland salinity. This article describes the first detailed investigation of the mosquito fauna of inland southwestern Australia, and it is the first description of the influence of secondary soil salinity on mosquito population dynamics. Despite the dominant presence of Ae. camptorhynchus, RRV disease incidence is not currently a significant population health priority in areas affected by dryland salinity. Potential limiting factors include local climatic impacts on the seasonal mosquito population dynamics, vertebrate host distribution and feeding behavior of Ae. camptorhynchus, and the scarce and uneven distribution of the human population in the region.

  1. Application of biogenic carbon dioxide produced by yeast with different carbon sources for attraction of mosquitoes towards adult mosquito traps.

    PubMed

    Sukumaran, D; Ponmariappan, S; Sharma, Atul K; Jha, Hemendra K; Wasu, Yogesh H; Sharma, Ajay K

    2016-04-01

    Surveillance is a prime requisite for controlling arthropod vectors like mosquitoes that transmit diseases such as malaria, dengue and chikungunya. Carbon dioxide (CO2) is one of the main cues from vertebrate breath that attracts mosquitoes towards the host. Hence, CO2 is used as an attractant during surveillance of mosquitoes either from commercial cylinders or dry ice for mosquito traps. In the present study, the biogenic carbon dioxide production was optimized with different carbon sources such as glucose, simple sugar and jaggery with and without yeast peptone dextrose (YPD) media using commercial baker's yeast. The results showed that yeast produced more biogenic CO2 with simple sugar as compared to other carbon sources. Further substrate concentration was optimized for the continuous production of biogenic CO2 for a minimum of 12 h by using 10 g of baker's yeast with 50 g of simple sugar added to 1.5 l distilled water (without YPD media) in a 2-l plastic bottle. This setup was applied in field condition along with two different mosquito traps namely Mosquito Killing System (MKS) and Biogents Sentinel (BGS) trap. Biogenic CO2 from this setup has increased the trapping efficiency of MKS by 6.48-fold for Culex quinquefasciatus, 2.62-fold for Aedes albopictus and 1.5-fold for Anopheles stephensi. In the case of BGS, the efficiency was found to be increased by 3.54-fold for Ae. albopictus, 4.33-fold for An. stephensi and 1.3-fold for Armigeres subalbatus mosquitoes. On the whole, plastic bottle setup releasing biogenic CO2 from sugar and yeast has increased the efficiency of MKS traps by 6.38-fold and 2.74-fold for BGS traps as compared to traps without biogenic CO2. The present study reveals that, among different carbon sources used, simple sugar as a substance (which is economical and readily available across the world) yielded maximum biogenic CO2 with yeast. This setup can be used as an alternative to CO2 cylinder and dry ice in any adult mosquito traps to

  2. Monitoring malaria vector control interventions: effectiveness of five different adult mosquito sampling methods.

    PubMed

    Onyango, Shirley A; Kitron, Uriel; Mungai, Peter; Muchiri, Eric M; Kokwaro, Elizabeth; King, Charles H; Mutuku, Francis M

    2013-09-01

    Long-term success of ongoing malaria control efforts based on mosquito bed nets (long-lasting insecticidal net) and indoor residual spraying is dependent on continuous monitoring of mosquito vectors, and thus on effective mosquito sampling tools. The objective of our study was to identify the most efficient mosquito sampling tool(s) for routine vector surveillance for malaria and lymphatic filariasis transmission in coastal Kenya. We evaluated relative efficacy of five collection methods--light traps associated with a person sleeping under a net, pyrethrum spray catches, Prokopack aspirator, clay pots, and urine-baited traps--in four villages representing three ecological settings along the south coast of Kenya. Of the five methods, light traps were the most efficient for collecting female Anopheles gambiae s.l. (Giles) (Diptera: Culicidae) and Anopheles funestus (Giles) (Diptera: Culicidae) mosquitoes, whereas the Prokopack aspirator was most efficient in collecting Culex quinquefasciatus (Say) (Diptera: Culicidae) and other culicines. With the low vector densities here, and across much of sub-Saharan Africa, wherever malaria interventions, long-lasting insecticidal nets, and/or indoor residual spraying are in place, the use of a single mosquito collection method will not be sufficient to achieve a representative sample of mosquito population structure. Light traps will remain a relevant tool for host-seeking mosquitoes, especially in the absence of human landing catches. For a fair representation of the indoor mosquito population, light traps will have to be supplemented with aspirator use, which has potential for routine monitoring of indoor resting mosquitoes, and can substitute the more labor-intensive and intrusive pyrethrum spray catches. There are still no sufficiently efficient mosquito collection methods for sampling outdoor mosquitoes, particularly those that are bloodfed.

  3. Monitoring Malaria Vector Control Interventions: Effectiveness of Five Different Adult Mosquito Sampling Methods

    PubMed Central

    Onyango, Shirley A.; Kitron, Uriel; Mungai, Peter; Muchiri, Eric M.; Kokwaro, Elizabeth; King, Charles H.; Mutuku, Francis M.

    2014-01-01

    Long-term success of ongoing malaria control efforts based on mosquito bed nets (long-lasting insecticidal net) and indoor residual spraying is dependent on continuous monitoring of mosquito vectors, and thus on effective mosquito sampling tools. The objective of our study was to identify the most efficient mosquito sampling tool(s) for routine vector surveillance for malaria and lymphatic filariasis transmission in coastal Kenya. We evaluated relative efficacy of five collection methods—light traps associated with a person sleeping under a net, pyrethrum spray catches, Prokopack aspirator, clay pots, and urine-baited traps—in four villages representing three ecological settings along the south coast of Kenya. Of the five methods, light traps were the most efficient for collecting female Anopheles gambiae s.l. (Giles) (Diptera: Culicidae) and Anopheles funestus (Giles) (Diptera: Culicidae) mosquitoes, whereas the Prokopack aspirator was most efficient in collecting Culex quinquefasciatus (Say) (Diptera: Culicidae) and other culicines. With the low vector densities here, and across much of sub-Saharan Africa, wherever malaria interventions, long-lasting insecticidal nets, and/or indoor residual spraying are in place, the use of a single mosquito collection method will not be sufficient to achieve a representative sample of mosquito population structure. Light traps will remain a relevant tool for host-seeking mosquitoes, especially in the absence of human landing catches. For a fair representation of the indoor mosquito population, light traps will have to be supplemented with aspirator use, which has potential for routine monitoring of indoor resting mosquitoes, and can substitute the more labor-intensive and intrusive pyrethrum spray catches. There are still no sufficiently efficient mosquito collection methods for sampling outdoor mosquitoes, particularly those that are bloodfed. PMID:24180120

  4. Anthropogenic impacts on mosquito populations in North America over the past century

    PubMed Central

    Rochlin, Ilia; Faraji, Ary; Ninivaggi, Dominick V.; Barker, Christopher M.; Kilpatrick, A. Marm

    2016-01-01

    The recent emergence and spread of vector-borne viruses including Zika, chikungunya and dengue has raised concerns that climate change may cause mosquito vectors of these diseases to expand into more temperate regions. However, the long-term impact of other anthropogenic factors on mosquito abundance and distributions is less studied. Here, we show that anthropogenic chemical use (DDT; dichlorodiphenyltrichloroethane) and increasing urbanization were the strongest drivers of changes in mosquito populations over the last eight decades in areas on both coasts of North America. Mosquito populations have increased as much as tenfold, and mosquito communities have become two- to fourfold richer over the last five decades. These increases are correlated with the decay in residual environmental DDT concentrations and growing human populations, but not with temperature. These results illustrate the far-reaching impacts of multiple anthropogenic disturbances on animal communities and suggest that interactions between land use and chemical use may have unforeseen consequences on ecosystems. PMID:27922001

  5. Anthropogenic impacts on mosquito populations in North America over the past century.

    PubMed

    Rochlin, Ilia; Faraji, Ary; Ninivaggi, Dominick V; Barker, Christopher M; Kilpatrick, A Marm

    2016-12-06

    The recent emergence and spread of vector-borne viruses including Zika, chikungunya and dengue has raised concerns that climate change may cause mosquito vectors of these diseases to expand into more temperate regions. However, the long-term impact of other anthropogenic factors on mosquito abundance and distributions is less studied. Here, we show that anthropogenic chemical use (DDT; dichlorodiphenyltrichloroethane) and increasing urbanization were the strongest drivers of changes in mosquito populations over the last eight decades in areas on both coasts of North America. Mosquito populations have increased as much as tenfold, and mosquito communities have become two- to fourfold richer over the last five decades. These increases are correlated with the decay in residual environmental DDT concentrations and growing human populations, but not with temperature. These results illustrate the far-reaching impacts of multiple anthropogenic disturbances on animal communities and suggest that interactions between land use and chemical use may have unforeseen consequences on ecosystems.

  6. Anthropogenic impacts on mosquito populations in North America over the past century

    NASA Astrophysics Data System (ADS)

    Rochlin, Ilia; Faraji, Ary; Ninivaggi, Dominick V.; Barker, Christopher M.; Kilpatrick, A. Marm

    2016-12-01

    The recent emergence and spread of vector-borne viruses including Zika, chikungunya and dengue has raised concerns that climate change may cause mosquito vectors of these diseases to expand into more temperate regions. However, the long-term impact of other anthropogenic factors on mosquito abundance and distributions is less studied. Here, we show that anthropogenic chemical use (DDT; dichlorodiphenyltrichloroethane) and increasing urbanization were the strongest drivers of changes in mosquito populations over the last eight decades in areas on both coasts of North America. Mosquito populations have increased as much as tenfold, and mosquito communities have become two- to fourfold richer over the last five decades. These increases are correlated with the decay in residual environmental DDT concentrations and growing human populations, but not with temperature. These results illustrate the far-reaching impacts of multiple anthropogenic disturbances on animal communities and suggest that interactions between land use and chemical use may have unforeseen consequences on ecosystems.

  7. Signatures of aestivation and migration in Sahelian malaria mosquito populations.

    PubMed

    Dao, A; Yaro, A S; Diallo, M; Timbiné, S; Huestis, D L; Kassogué, Y; Traoré, A I; Sanogo, Z L; Samaké, D; Lehmann, T

    2014-12-18

    During the long Sahelian dry season, mosquito vectors of malaria are expected to perish when no larval sites are available; yet, days after the first rains, mosquitoes reappear in large numbers. How these vectors persist over the 3-6-month long dry season has not been resolved, despite extensive research for over a century. Hypotheses for vector persistence include dry-season diapause (aestivation) and long-distance migration (LDM); both are facets of vector biology that have been highly controversial owing to lack of concrete evidence. Here we show that certain species persist by a form of aestivation, while others engage in LDM. Using time-series analyses, the seasonal cycles of Anopheles coluzzii, Anopheles gambiae sensu stricto (s.s.), and Anopheles arabiensis were estimated, and their effects were found to be significant, stable and highly species-specific. Contrary to all expectations, the most complex dynamics occurred during the dry season, when the density of A. coluzzii fluctuated markedly, peaking when migration would seem highly unlikely, whereas A. gambiae s.s. was undetected. The population growth of A. coluzzii followed the first rains closely, consistent with aestivation, whereas the growth phase of both A. gambiae s.s. and A. arabiensis lagged by two months. Such a delay is incompatible with local persistence, but fits LDM. Surviving the long dry season in situ allows A. coluzzii to predominate and form the primary force of malaria transmission. Our results reveal profound ecological divergence between A. coluzzii and A. gambiae s.s., whose standing as distinct species has been challenged, and suggest that climate is one of the selective pressures that led to their speciation. Incorporating vector dormancy and LDM is key to predicting shifts in the range of malaria due to global climate change, and to the elimination of malaria from Africa.

  8. Use of geographic information systems to depict and analyze mosquito population trends.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mosquitoes transmit (vector) disease agents that cause malaria, yellow fever, dengue, West Nile fever, and encephalitis. Spread of these diseases is controlled by the management of mosquito population levels, changes in which are monitored in vector surveillance programs by the use of mechanical tr...

  9. Established Population of the Invasive Mosquito Species Aedes albopictus in Romania, 2012-14.

    PubMed

    Prioteasa, Liviu F; Dinu, Sorin; Fălcuţă, Elena; Ceianu, Cornelia S

    2015-06-01

    During an entomological investigation carried out in Bucharest and surroundings in fall of 2012, 45 adult mosquitoes (38 females and 7 males) of Aedes albopictus were collected in a neighborhood from the southern area of the city. The morphological identification of the species was further confirmed by sequencing 2 mitochondrial DNA markers: the cytochrome c oxidase subunit I and NADH dehydrogenase subunit 5 genes. Aedes albopictus was collected again in 2013 in the same area from July until October. During late summer the species was found also in another location in the city, downtown Bucharest. Larvae were found in water barrels and other types of household containers, as well as in rain catch basins. In 2014, following a nuisance complaint of a Bucharest inhabitant, the entomological investigation found aggressive Ae. albopictus adults on his property that harbored many mosquito larvae in container-type breeding habitats. These findings are the 1st records of this invasive species and of its breeding population in Romania, and show maintenance of the species over 2 winter seasons. Surveillance of the species outside the area of the capital city was not performed, therefore it is not known whether Ae. albopictus has been introduced in other regions of the country. The presence of Ae. albopictus has been reported every year (2012-14) to competent public health authorities, stressing on the importance of surveillance and of implementation of control measures.

  10. Mosquito Larvae in Tires from Mississippi, United States: The Efficacy of Abiotic and Biotic Parameters in Predicting Spatial and Temporal Patterns of Mosquito Populations and Communities

    PubMed Central

    Yee, Donald A.; Abuzeineh, Alisa A.; Ezeakacha, Nnaemeka F.; Schelble, Stephanie S.; Glasgow, William C.; Flanagan, Stephen D.; Skiff, Jeffrey J.; Reeves, Ashton; Kuehn, Kevin

    2015-01-01

    Container systems, including discarded vehicle tires, which support populations of mosquitoes, have been of interest for understanding the variables that produce biting adults that serve as both nuisances and as public health threats. We sampled tires in six sites at three times in 2012 across the state of Mississippi to understand the biotic and abiotic variables responsible for explaining patterns of larvae of common species, species richness, and total abundance of mosquitoes. From 498 tires sampled, we collected >58,000 immatures representing 16 species, with the most common species including Aedes albopictus (Skuse), Culex quinquefasciatus (L.), Orthopodomyia signifera (Coquillett), Aedes triseriatus (Say), Toxorhynchites rutilus septentrionalis (Coquillett), and Culex territans (Walker) accounting for ∼97% of all larvae. We also documented 32 new county records for resident species and recent arrivals in the state, including Aedes japonicus japonicus (Theobald) and Culex coronator (Dyar & Knab). Cluster analysis, which was used to associate sites and time periods based on similar mosquito composition, did reveal patterns across the state; however, there also were more general patterns between species and genera and environmental factors. Broadly, Aedes was often associated with factors related to detritus, whereas Culex was frequently associated with habitat variables (e.g., tire size and water volume) and microorganisms. Some Culex did lack factors connecting variation in early and late instars, suggesting differences between environmental determinants of oviposition and survival. General patterns between the tire environment and mosquito larvae do appear to exist, especially at the generic level, and point to inherent differences between genera that may aid in predicting vector locations and populations. PMID:26334813

  11. Mosquito Larvae in Tires from Mississippi, United States: The Efficacy of Abiotic and Biotic Parameters in Predicting Spatial and Temporal Patterns of Mosquito Populations and Communities.

    PubMed

    Yee, Donald A; Abuzeineh, Alisa A; Ezeakacha, Nnaemeka F; Schelble, Stephanie S; Glasgow, William C; Flanagan, Stephen D; Skiff, Jeffrey J; Reeves, Ashton; Kuehn, Kevin

    2015-05-01

    Container systems, including discarded vehicle tires, which support populations of mosquitoes, have been of interest for understanding the variables that produce biting adults that serve as both nuisances and as public health threats. We sampled tires in six sites at three times in 2012 across the state of Mississippi to understand the biotic and abiotic variables responsible for explaining patterns of larvae of common species, species richness, and total abundance of mosquitoes. From 498 tires sampled, we collected >58,000 immatures representing 16 species, with the most common species including Aedes albopictus (Skuse), Culex quinquefasciatus (L.), Orthopodomyia signifera (Coquillett), Aedes triseriatus (Say), Toxorhynchites rutilus septentrionalis (Coquillett), and Culex territans (Walker) accounting for ∼97% of all larvae. We also documented 32 new county records for resident species and recent arrivals in the state, including Aedes japonicus japonicus (Theobald) and Culex coronator (Dyar & Knab). Cluster analysis, which was used to associate sites and time periods based on similar mosquito composition, did reveal patterns across the state; however, there also were more general patterns between species and genera and environmental factors. Broadly, Aedes was often associated with factors related to detritus, whereas Culex was frequently associated with habitat variables (e.g., tire size and water volume) and microorganisms. Some Culex did lack factors connecting variation in early and late instars, suggesting differences between environmental determinants of oviposition and survival. General patterns between the tire environment and mosquito larvae do appear to exist, especially at the generic level, and point to inherent differences between genera that may aid in predicting vector locations and populations.

  12. Diel activity patterns of major species of adult mosquitoes and ULV spraying impacts in St. John's County, Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of daily activity patterns in adult mosquitoes can be used to determine the best time to apply adulticides for mosquito control. Many factors influence these activity patterns, including migration, hormonal cycles in the mosquito, hunger, and the need to lay eggs. In this study, FL scien...

  13. Weather and land cover influences on mosquito populations in Sioux Falls, South Dakota.

    PubMed

    Chuang, Ting-Wu; Hildreth, Michael B; Vanroekel, Denise L; Wimberly, Michael C

    2011-05-01

    This study compared the spatial and temporal patterns of Culex tarsalis Coquillett and Aedes vexans Meigen populations and examined their relationships with land cover types and climatic variability in Sioux Falls, SD. Between 24 and 30 CDC CO2-baited light traps were set annually in Sioux Falls from May to September 2005-2008. Land cover data were acquired from the 2001 National Land Cover Dataset and the percentages of selected land cover types were calculated within a 600-m buffer zone around each trap. Meteorological information was summarized from local weather stations. Cx. tarsalis exhibited stronger spatial autocorrelation than Ae. vexans. Land cover analysis indicated that Cx. tarsalis was positively correlated with grass/hay, and Ae. vexans was positively correlated with wetlands. No associations were identified between irrigation and the host-seeking population of each species. Higher temperature in the current week and 2 wk prior and higher precipitation 3-4 wk before collection of host-seeking adult mosquitoes had positive influences on Cx. tarsalis abundance. Temperature in the current week and rainfall 2-3 wk before sampling had positive influences on Ae. vexans abundance. This study revealed the different influences of weather and land cover on important mosquito species in the Northern Great Plains region, which can be used to improve local vector control strategies and West Nile virus prevention efforts.

  14. Weather and Land Cover Influences on Mosquito Populations in Sioux Falls, South Dakota

    PubMed Central

    CHUANG, TING-WU; HILDRETH, MICHAEL B.; VANROEKEL, DENISE L.; WIMBERLY, MICHAEL C.

    2011-01-01

    This study compared the spatial and temporal patterns of Culex tarsalis Coquillett and Aedes vexans Meigen populations and examined their relationships with land cover types and climatic variability in Sioux Falls, SD. Between 24 and 30 CDC CO2-baited light traps were set annually in Sioux Falls from May to September 2005–2008. Land cover data were acquired from the 2001 National Land Cover Dataset and the percentages of selected land cover types were calculated within a 600-m buffer zone around each trap. Meteorological information was summarized from local weather stations. Cx. tarsalis exhibited stronger spatial autocorrelation than Ae. vexans. Land cover analysis indicated that Cx. tarsalis was positively correlated with grass/hay, and Ae. vexans was positively correlated with wetlands. No associations were identified between irrigation and the host-seeking population of each species. Higher temperature in the current week and 2 wk prior and higher precipitation 3–4 wk before collection of host-seeking adult mosquitoes had positive influences on Cx. tarsalis abundance. Temperature in the current week and rainfall 2–3 wk before sampling had positive influences on Ae. vexans abundance. This study revealed the different influences of weather and land cover on important mosquito species in the Northern Great Plains region, which can be used to improve local vector control strategies and West Nile virus prevention efforts. PMID:21661329

  15. Mosquito fauna and perspectives for integrated control of urban vector-mosquito populations in Southern Benin (West Africa).

    PubMed

    Lingenfelser, Andre; Rydzanicz, Katarzyna; Kaiser, Achim; Becker, Norbert

    2010-01-01

    This study aims at an integrated vector management (IVM) concept of implementing biological control agents against vector mosquito larvae as a cost-effective and scalable control strategy. In the first step, the mosquito species composition fauna of southern Benin was studied using standard entomological procedures in natural and man-made habitats. Altogether, 24 species belonging to 6 genera of mosquitoes Aedes, Anopheles, Culex, Mansonia, Uranotaenia, Ficalbia were recorded. Five species, Cx. thalassius, Cx. nebulosus, Cx. perfuscus, Cx. pocilipes and Fi. mediolineata are described the first time for Benin. The local mosquito species showed high susceptibility to a Bacillus sphaericus formulation (VectoLex(R) WDG ) in a standardized field test. A dosage of 1 g/m(2) was effective to achieve 100 percent mortality rate for Cx. quinquefasciatus late instar larvae in a sewage habitat, with a residual effect of up to 7 days. After more than 1 year of baseline data collection, operational larviciding with B. thuringiensis var. israelensis and B. sphaericus was commenced in 2006 in selected areas. Microbial insecticides products for larval control show great potential within IVM programmes and may augment control efforts against adult insects, such as the use of insecticide-treated bed nets or indoor wall spraying in many parts of Africa.

  16. New Clues to Huge Jump in U.S. Mosquito Population

    MedlinePlus

    ... Clues to Huge Jump in U.S. Mosquito Population Urbanization, DDT pesticide ban played roles, but climate change ... past 50 years in certain U.S. states: Increased urbanization and shrinking levels of the pesticide DDT in ...

  17. A critical review of ultralow-volume aerosols of insecticide applied with vehicle-mounted generators for adult mosquito control.

    PubMed

    Mount, G A

    1998-09-01

    , temperature, and atmospheric stability and turbulence. 7) Maximum effective swaths are obtained with aerosols in the optimum VMD range during favorable meteorological conditions in open to moderately open terrain. The insecticide dosage must be increased in proportion to increased swath to maintain the same level of mosquito control. 8) Dispersal speed within a range of 2.5-20 mph is not a factor affecting efficacy if insecticide rate and optimum droplet size are maintained. 9) The results of caged mosquito assays are comparable with reductions in free-flying natural populations. 10) The field efficacies of mosquito adulticides applied as ULV ground aerosols are predictable from the results of laboratory wind-tunnel tests. 11) Results of field tests in open to moderately open terrain during favorable meteorological conditions indicated that ULV insecticidal aerosol application rates producing 90% or more control of Anopheles, Culex, and Psorophora spp. are below or approximately equal to maximum United States Environmental Protection Agency label rates. Against some Aedes spp., some pyrethroid insecticides must be synergized to produce 90% control at label rates. 12) Results of field tests in residential areas with moderate to dense vegetation and in citrus groves or other densely wooded areas showed that insecticide rates of ULV ground aerosols must be increased 2-3-fold to obtain 90% or more control of adult mosquitoes. However, the maximum rates on some insecticide labels would have to be increased to allow higher application rates. 13) Applications of ULV ground aerosols of insecticide in accordance with label directions following sunset do not pose a serious threat to humans, nontarget beneficial animals, or automotive paints. 14) Some aerosol generators operated at high RPM levels exceed the OSHA 8-h hearing hazard criteria of 90 dBA and may require hearing protectors for operators.

  18. Combining Hydrology and Mosquito Population Models to Identify the Drivers of Rift Valley Fever Emergence in Semi-Arid Regions of West Africa

    PubMed Central

    Soti, Valérie; Tran, Annelise; Degenne, Pascal; Chevalier, Véronique; Lo Seen, Danny; Thiongane, Yaya; Diallo, Mawlouth; Guégan, Jean-François; Fontenille, Didier

    2012-01-01

    Background Rift Valley fever (RVF) is a vector-borne viral zoonosis of increasing global importance. RVF virus (RVFV) is transmitted either through exposure to infected animals or through bites from different species of infected mosquitoes, mainly of Aedes and Culex genera. These mosquitoes are very sensitive to environmental conditions, which may determine their presence, biology, and abundance. In East Africa, RVF outbreaks are known to be closely associated with heavy rainfall events, unlike in the semi-arid regions of West Africa where the drivers of RVF emergence remain poorly understood. The assumed importance of temporary ponds and rainfall temporal distribution therefore needs to be investigated. Methodology/Principal Findings A hydrological model is combined with a mosquito population model to predict the abundance of the two main mosquito species (Aedes vexans and Culex poicilipes) involved in RVFV transmission in Senegal. The study area is an agropastoral zone located in the Ferlo Valley, characterized by a dense network of temporary water ponds which constitute mosquito breeding sites. The hydrological model uses daily rainfall as input to simulate variations of pond surface areas. The mosquito population model is mechanistic, considers both aquatic and adult stages and is driven by pond dynamics. Once validated using hydrological and entomological field data, the model was used to simulate the abundance dynamics of the two mosquito species over a 43-year period (1961–2003). We analysed the predicted dynamics of mosquito populations with regards to the years of main outbreaks. The results showed that the main RVF outbreaks occurred during years with simultaneous high abundances of both species. Conclusion/Significance Our study provides for the first time a mechanistic insight on RVFV transmission in West Africa. It highlights the complementary roles of Aedes vexans and Culex poicilipes mosquitoes in virus transmission, and recommends the

  19. Population genetic structure of Anopheles gambiae mosquitoes on Lake Victoria islands, west Kenya

    PubMed Central

    Chen, Hong; Minakawa, Noboru; Beier, John; Yan, Guiyun

    2004-01-01

    Background Understanding the genetic structure of island Anopheles gambiae populations is important for the current tactics in mosquito control and for the proposed strategy using genetically-modified mosquitoes (GMM). Genetically-isolated mosquito populations on islands are a potential site for testing GMM. The objective of this study was to determine the genetic structure of A. gambiae populations on the islands in Lake Victoria, western Kenya. Methods The genetic diversity and the population genetic structures of 13 A. gambiae populations from five islands on Lake Victoria and six villages from the surrounding mainland area in the Suba District were examined using six microsatellite markers. The distance range of sampling sites varied between 2.5 and 35.1 km. Results A similar level of genetic diversity between island mosquito populations and adjacent mainland populations was found. The average number of alleles per locus was 7.3 for the island populations and 6.8 for the mainland populations. The average observed heterozygosity was 0.32 and 0.28 for the island and mainland populations, respectively. A low but statistically significant genetic structure was detected among the island populations (FST = 0.019) and between the island and mainland populations (FST = 0.003). A total of 12 private alleles were found, and nine of them were from the island populations. Conclusion A level of genetic differentiation between the island and mainland populations was found. Large extent of gene flow between the island and mainland mosquito populations may result from wind- or human-assisted dispersal. Should the islands on Lake Victoria be used as a trial site for the release program of GMM, mosquito dispersal between the islands and between the island and the mainland should be vigorously monitored. PMID:15581429

  20. Glass, rubber, and nylon: how to make a mouth aspirator on a budget for handling adult mosquitoes.

    PubMed

    Farajollahi, Ary; Condon, George C; Campbell, Ernest E; McCuiston, Linda

    2011-12-01

    A mouth aspirator with a bent glass tip was designed for adult mosquito collection and transportation. This aspirator has been utilized for mosquito laboratory and operational research in New Jersey for >60 years. We provide schematics and instruction for construction of this inexpensive and simple mouth aspirator, which offers improved maneuverability of handling adult mosquitoes from rearing cages in the laboratory and field application cages.

  1. Mosquitoes of the Caatinga: 1. Adults stage survey and the emerge of seven news species endemic of a dry tropical forest in Brazil.

    PubMed

    Marteis, Letícia Silva; Natal, Delsio; Sallum, Maria Anice Mureb; Medeiros-Sousa, Antônio Ralph; Oliveira, Tatiane Marques Porangaba; La Corte, Roseli

    2017-02-01

    The Caatinga is the least known Brazilian biome in terms of the diversity of Culicidae. No systematic study of the diversity or ecology of the mosquitoes of this biome is available, despite the importance of vector diseases in Brazil. The present study addressed the mosquito biodiversity in the Caatinga biome by sampling adult populations. Specimens were sampled monthly from March 2013 to September 2014 in a Caatinga conservation unit located in the Brazilian semiarid zone. Mosquito collections were carried out in Shannon traps from late afternoon to early evening, and manual aspiration was used to capture diurnal species as well. A total of 4,692 mosquitoes were collected. The most dominant and constant species were all undescribed species belonging to the genera Wyeomyia and Runchomyia, which together represented 80% of the specimens. The most abundant species of epidemiological importance was Haemagogus (Con.) leucocelaenus. The abundance of mosquitoes was positively associated with the relative humidity and temperature recorded during the month preceding the collection date. In the Caatinga, the diversity of adult mosquitoes was associated with the availability (quantity and diversity) of natural larval habitats found in the different phytophysiognomies of the biome, which vary according to temperature and humidity. The number of species unknown to science reflects the levels of endemism that exist in the study area, and reinforces the need to further taxonomic investigation in the biome.

  2. A web-based relational database for monitoring and analyzing mosquito population dynamics.

    PubMed

    Sucaet, Yves; Van Hemert, John; Tucker, Brad; Bartholomay, Lyric

    2008-07-01

    Mosquito population dynamics have been monitored on an annual basis in the state of Iowa since 1969. The primary goal of this project was to integrate light trap data from these efforts into a centralized back-end database and interactive website that is available through the internet at http://iowa-mosquito.ent.iastate.edu. For comparative purposes, all data were categorized according to the week of the year and normalized according to the number of traps running. Users can readily view current, weekly mosquito abundance compared with data from previous years. Additional interactive capabilities facilitate analyses of the data based on mosquito species, distribution, or a time frame of interest. All data can be viewed in graphical and tabular format and can be downloaded to a comma separated value (CSV) file for import into a spreadsheet or more specialized statistical software package. Having this long-term dataset in a centralized database/website is useful for informing mosquito and mosquito-borne disease control and for exploring the ecology of the species represented therein. In addition to mosquito population dynamics, this database is available as a standardized platform that could be modified and applied to a multitude of projects that involve repeated collection of observational data. The development and implementation of this tool provides capacity for the user to mine data from standard spreadsheets into a relational database and then view and query the data in an interactive website.

  3. Artificial natural selection: can supplemental feeding domesticate mosquitoes and control mosquito-borne diseases?

    PubMed

    Egeth, Marc; Kurzban, Robert

    2012-08-29

    A new method is proposed for controlling mosquito-borne diseases. In particular, instead of trying to kill mosquitoes, we suggest provisioning them with food from artificial feeders. Because mosquito populations are frequently limited by ecological factors other than blood meals, such as the availability of egg-laying sites, feeding mosquitoes would not necessarily increase the total number of mosquitoes, but could reduce the number of human-drawn mosquito meals. Like mosquito traps, feeders could divert biting mosquitoes away from people by means of lures, but, after diversion, prevent subsequent human bites by satiating the mosquitoes instead of killing them. Mosquito feeders might reduce the problem of the evolution of resistance to control: in an ecology with mosquito feeders, which provide safe and abundant calories for adult female mosquitoes, there could be selection for preferring (rather than avoiding) feeders, which could eventually lead to a population of feeder-preferring mosquitoes. Artificial feeders also offer the chance to introduce novel elements into the mosquito diet, such as anti- malarial or other anti-parasitic agents. Feeders might directly reduce human bites and harnesses the power of natural selection by selectively favoring feeder-preferring (rather than trap-resistant) mosquitoes.

  4. Monitoring population and environmental parameters of invasive mosquito species in Europe

    PubMed Central

    2014-01-01

    To enable a better understanding of the overwhelming alterations in the invasive mosquito species (IMS), methodical insight into the population and environmental factors that govern the IMS and pathogen adaptations are essential. There are numerous ways of estimating mosquito populations, and usually these describe developmental and life-history parameters. The key population parameters that should be considered during the surveillance of invasive mosquito species are: (1) population size and dynamics during the season, (2) longevity, (3) biting behaviour, and (4) dispersal capacity. Knowledge of these parameters coupled with vector competence may help to determine the vectorial capacity of IMS and basic disease reproduction number (R0) to support mosquito borne disease (MBD) risk assessment. Similarly, environmental factors include availability and type of larval breeding containers, climate change, environmental change, human population density, increased human travel and goods transport, changes in living, agricultural and farming habits (e.g. land use), and reduction of resources in the life cycle of mosquitoes by interventions (e.g. source reduction of aquatic habitats). Human population distributions, urbanisation, and human population movement are the key behavioural factors in most IMS-transmitted diseases. Anthropogenic issues are related to the global spread of MBD such as the introduction, reintroduction, circulation of IMS and increased exposure to humans from infected mosquito bites. This review addresses the population and environmental factors underlying the growing changes in IMS populations in Europe and confers the parameters selected by criteria of their applicability. In addition, overview of the commonly used and newly developed tools for their monitoring is provided. PMID:24739334

  5. Susceptibility of adult mosquitoes to insecticides in aqueous sucrose baits.

    PubMed

    Allan, Sandra A

    2011-06-01

    Mosquitoes characteristically feed on plant-derived carbohydrates and honeydew just after emergence and intermittently during their lives. Development of toxic baits focusing on this carbohydrate-seeking behavior may potentially contribute to localized control. In the present study, ten insecticides were fed to female Culex quinquefasciatus, Anopheles quadrimaculatus, and Aedes taeniorhynchus in a 10% sucrose solution. Active ingredients representative of five classes of insecticides (pyrethroids, phenylpyroles, pyrroles, neonicotinoids, and macrocyclic lactones) were selected for comparison with commercial formulations used to facilitate incorporation of active ingredients into aqueous sucrose solutions. Sucrose as a phagostimulant significantly enhanced mortality to toxicants. In general, the most effective active ingredients were fipronil, deltamethrin and imidacloprid, followed by spinosad, thiamethoxam, bifenthrin, permethrin, and cyfluthrin. The least effective ingredients were chlorfenapyr and ivermectin. For some of the ingredients tested, Cx. quinquefasciatus was the least susceptible species. One-day-old male Cx. quinquefasciatus were more susceptible than females; however, no differences existed between one- and seven-day-old mosquitoes. There were no differences in susceptibility between unfed and gravid ten-day-old female Cx. quinquefasciatus to bifenthrin. In conclusion, several pesticides from different classes of compounds have potential for use in development of toxic baits for mosquitoes.

  6. Aerial ULV application of permethrin against adult mosquitoes in an extreme hot-arid zone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aerial ULV insecticide application is an established strategy for adult mosquito control in tropical, hot-humid, or temperate environments. However, not enough is known regarding the efficacy of aerial applications in hot-arid environments similar to those encountered by US military personnel, where...

  7. A generic weather-driven model to predict mosquito population dynamics applied to species of Anopheles, Culex and Aedes genera of southern France.

    PubMed

    Ezanno, P; Aubry-Kientz, M; Arnoux, S; Cailly, P; L'Ambert, G; Toty, C; Balenghien, T; Tran, A

    2015-06-01

    An accurate understanding and prediction of mosquito population dynamics are needed to identify areas where there is a high risk of mosquito-borne disease spread and persistence. Simulation tools are relevant for supporting decision-makers in the surveillance of vector populations, as models of vector population dynamics provide predictions of the greatest risk periods for vector abundance, which can be particularly helpful in areas with a highly variable environment. We present a generic weather-driven model of mosquito population dynamics, which was applied to one species of each of the genera Anopheles, Culex, and Aedes, located in the same area and thus affected by similar weather conditions. The predicted population dynamics of Anopheles hyrcanus, Culex pipiens, and Aedes caspius were not similar. An. hyrcanus was abundant in late summer. Cx. pipiens was less abundant but throughout the summer. The abundance of both species showed a single large peak with few variations between years. The population dynamics of Ae. caspius showed large intra- and inter-annual variations due to pulsed egg hatching. Predictions of the model were compared to longitudinal data on host-seeking adult females. Data were previously obtained using CDC-light traps baited with carbon dioxide dry ice in 2005 at two sites (Marais du Viguerat and Tour Carbonnière) in a favourable temperate wetland of southern France (Camargue). The observed and predicted periods of maximal abundance for An. hyrcanus and Cx. pipiens tallied very well. Pearson's coefficients for these two species were over 75% for both species. The model also reproduced the major trends in the intra-annual fluctuations of Ae. caspius population dynamics, with peaks occurring in early summer and following the autumn rainfall events. Few individuals of this species were trapped so the comparison of predicted and observed dynamics was not relevant. A global sensitivity analysis of the species-specific models enabled us to

  8. The Role of Climatic and Density Dependent Factors in Shaping Mosquito Population Dynamics: The Case of Culex pipiens in Northwestern Italy

    PubMed Central

    Giacobini, Mario; Pugliese, Andrea; Merler, Stefano; Rosà, Roberto

    2016-01-01

    Culex pipiens mosquito is a species widely spread across Europe and represents a competent vector for many arboviruses such as West Nile virus (WNV), which has been recently circulating in many European countries, causing hundreds of human cases. In order to identify the main determinants of the high heterogeneity in Cx. pipiens abundance observed in Piedmont region (Northwestern Italy) among different seasons, we developed a density-dependent stochastic model that takes explicitly into account the role played by temperature, which affects both developmental and mortality rates of different life stages. The model was calibrated with a Markov chain Monte Carlo approach exploring the likelihood of recorded capture data gathered in the study area from 2000 to 2011; in this way, we disentangled the role played by different seasonal eco-climatic factors in shaping the vector abundance. Illustrative simulations have been performed to forecast likely changes if temperature or density–dependent inputs would change. Our analysis suggests that inter-seasonal differences in the mosquito dynamics are largely driven by different temporal patterns of temperature and seasonal-specific larval carrying capacities. Specifically, high temperatures during early spring hasten the onset of the breeding season and increase population abundance in that period, while, high temperatures during the summer can decrease population size by increasing adult mortality. Higher densities of adult mosquitoes are associated with higher larval carrying capacities, which are positively correlated with spring precipitations. Finally, an increase in larval carrying capacity is expected to proportionally increase adult mosquito abundance. PMID:27105065

  9. The Effective Population Size of Malaria Mosquitoes: Large Impact of Vector Control

    PubMed Central

    Athrey, Giridhar; Hodges, Theresa K.; Reddy, Michael R.; Overgaard, Hans J.; Matias, Abrahan; Ridl, Frances C.; Kleinschmidt, Immo; Caccone, Adalgisa; Slotman, Michel A.

    2012-01-01

    Malaria vectors in sub-Saharan Africa have proven themselves very difficult adversaries in the global struggle against malaria. Decades of anti-vector interventions have yielded mixed results—with successful reductions in transmission in some areas and limited impacts in others. These varying successes can be ascribed to a lack of universally effective vector control tools, as well as the development of insecticide resistance in mosquito populations. Understanding the impact of vector control on mosquito populations is crucial for planning new interventions and evaluating existing ones. However, estimates of population size changes in response to control efforts are often inaccurate because of limitations and biases in collection methods. Attempts to evaluate the impact of vector control on mosquito effective population size (Ne) have produced inconclusive results thus far. Therefore, we obtained data for 13–15 microsatellite markers for more than 1,500 mosquitoes representing multiple time points for seven populations of three important vector species—Anopheles gambiae, An. melas, and An. moucheti—in Equatorial Guinea. These populations were exposed to indoor residual spraying or long-lasting insecticidal nets in recent years. For comparison, we also analyzed data from two populations that have no history of organized vector control. We used Approximate Bayesian Computation to reconstruct their demographic history, allowing us to evaluate the impact of these interventions on the effective population size. In six of the seven study populations, vector control had a dramatic impact on the effective population size, reducing Ne between 55%–87%, the exception being a single An. melas population. In contrast, the two negative control populations did not experience a reduction in effective population size. This study is the first to conclusively link anti-vector intervention programs in Africa to sharply reduced effective population sizes of malaria vectors

  10. An Efficient Method for Transferring Adult Mosquitoes during Field Tests,

    DTIC Science & Technology

    CULICIDAE, *COLLECTING METHODS, REPRINTS, BLOOD SUCKING INSECTS, FIELD TESTS, HAND HELD, EFFICIENCY, LABORATORY EQUIPMENT, MORTALITY RATES , ADULTS, AEDES, ASPIRATORS, CULICIDAE, TEST AND EVALUATION, REPRINTS

  11. Using global information technology to detect, monitor, and control mosquito pest and disease vector populations.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Geographic Information Systems (GIS), image analysis, and remote sensing comprise global information technologies that are used to characterize pest and vector populations of mosquitoes. At this national meeting, scientists from ARS and McNeese State University organized and convened a half-day sym...

  12. 16S rRNA gene sequences from bacteria associated with adult Anopheles darlingi (Diptera: Culicidae) mosquitoes.

    PubMed

    Terenius, Olle; de Oliveira, Caroline Dantas; Pinheiro, Waleria Dasso; Tadei, Wanderli Pedro; James, Anthony Amade; Marinotti, Osvaldo

    2008-01-01

    The microbial flora associated with Anopheles darlingi Root (Diptera: Culicidae), a major Neotropical malaria vector, was investigated for the development of a paratransgenesis-based approach to control malaria transmission in Brazil. Female mosquitoes were collected using human land catches and captured insects provided a bloodmeal. The controlled blood feeding resulted in increased detection of mosquito bacterial population because it was possible to retrieve bacterial DNA from all blood-fed mosquitoes. The 16S sequences of bacteria recovered, include some closely related to those found in other vector mosquitoes, including Aeromonas, Pantoea and Pseudomonas species.

  13. HIV/AIDS Misconceptions among Latinos: Findings from a Population-Based Survey of California Adults

    ERIC Educational Resources Information Center

    Ritieni, Assunta; Moskowitz, Joel; Tholandi, Maya

    2008-01-01

    Misconceptions about HIV/AIDS among Latino adults (N=454) in California were examined using data from a population-based telephone survey conducted in 2000. Common misconceptions concerning modes of HIV transmission included transmission via mosquito or animal bite (64.1%), public facilities (48.3%), or kissing someone on the cheek (24.8%). A…

  14. Environmental Fate Model for Ultra-Low-Volume Insecticide Applications Used for Adult Mosquito Management

    DTIC Science & Technology

    2012-01-01

    drift hazard (Hewitt, 2008; Teske et al., 2000). Little is currently known about the deposition and drift of small droplets such as those used during...ULV applications for adult mosquito management ( Teske et al., 2000). Droplets smaller than 50 μm have very low settling velocities, and have similar...risk and regulatory assessments have used models like ISCST3, AgDrift® (Stewart Agricultural Research Services, Macon, MO, USA) ( Teske et al., 2002), and

  15. Productivity and population density estimates of the dengue vector mosquito Aedes aegypti (Stegomyia aegypti) in Australia.

    PubMed

    Williams, C R; Johnson, P H; Ball, T S; Ritchie, S A

    2013-09-01

    New mosquito control strategies centred on the modifying of populations require knowledge of existing population densities at release sites and an understanding of breeding site ecology. Using a quantitative pupal survey method, we investigated production of the dengue vector Aedes aegypti (L.) (Stegomyia aegypti) (Diptera: Culicidae) in Cairns, Queensland, Australia, and found that garden accoutrements represented the most common container type. Deliberately placed 'sentinel' containers were set at seven houses and sampled for pupae over 10 weeks during the wet season. Pupal production was approximately constant; tyres and buckets represented the most productive container types. Sentinel tyres produced the largest female mosquitoes, but were relatively rare in the field survey. We then used field-collected data to make estimates of per premises population density using three different approaches. Estimates of female Ae. aegypti abundance per premises made using the container-inhabiting mosquito simulation (CIMSiM) model [95% confidence interval (CI) 18.5-29.1 females] concorded reasonably well with estimates obtained using a standing crop calculation based on pupal collections (95% CI 8.8-22.5) and using BG-Sentinel traps and a sampling rate correction factor (95% CI 6.2-35.2). By first describing local Ae. aegypti productivity, we were able to compare three separate population density estimates which provided similar results. We anticipate that this will provide researchers and health officials with several tools with which to make estimates of population densities.

  16. Mosquito species (Diptera, Culicidae) in three ecosystems from the Colombian Andes: identification through DNA barcoding and adult morphology.

    PubMed

    Rozo-Lopez, Paula; Mengual, Ximo

    2015-01-01

    Colombia, one of the world's megadiverse countries, has a highly diverse mosquito fauna and a high prevalence of mosquito-borne diseases. In order to provide relevant information about the diversity and taxonomy of mosquito species in Colombia and to test the usefulness of DNA barcodes, mosquito species collected at different elevations in the departments of Antioquia and Caldas were identified combining adult morphology and barcode sequences. A total of 22 mosquito species from eight genera were identified using these combined techniques. We generated 77 barcode sequences with 16 species submitted as new country records for public databases. We examined the usefulness of DNA barcodes to discriminate mosquito species from the Neotropics by compiling 1,292 sequences from a total of 133 species and using the tree-based methods of neighbor-joining and maximum likelihood. Both methodologies provided similar results by resolving 105 species of mosquitoes separated into distinct clusters. This study shows the importance of combining classic morphological methodologies with molecular tools to accurately identify mosquitoes from Colombia.

  17. Mosquito species (Diptera, Culicidae) in three ecosystems from the Colombian Andes: identification through DNA barcoding and adult morphology

    PubMed Central

    Rozo-Lopez, Paula; Mengual, Ximo

    2015-01-01

    Abstract Colombia, one of the world’s megadiverse countries, has a highly diverse mosquito fauna and a high prevalence of mosquito-borne diseases. In order to provide relevant information about the diversity and taxonomy of mosquito species in Colombia and to test the usefulness of DNA barcodes, mosquito species collected at different elevations in the departments of Antioquia and Caldas were identified combining adult morphology and barcode sequences. A total of 22 mosquito species from eight genera were identified using these combined techniques. We generated 77 barcode sequences with 16 species submitted as new country records for public databases. We examined the usefulness of DNA barcodes to discriminate mosquito species from the Neotropics by compiling 1,292 sequences from a total of 133 species and using the tree-based methods of neighbor-joining and maximum likelihood. Both methodologies provided similar results by resolving 105 species of mosquitoes separated into distinct clusters. This study shows the importance of combining classic morphological methodologies with molecular tools to accurately identify mosquitoes from Colombia. PMID:26257568

  18. Hydrology and Mosquito Population Dynamics around a Hydropower Reservoir in Africa

    NASA Astrophysics Data System (ADS)

    Endo, N.; Eltahir, E. A.

    2013-12-01

    Malaria is associated with dams because their reservoirs provide mosquitoes, the vector of malaria, with permanent breeding sites. The risk of contracting malaria is likely to be enhanced following the increasing trend of hydropower dam construction to satisfy the expanding energy needs in developing countries. A close examination of its adverse health impacts is critical in the design, construction, and operation phases. We will present results of extensive field studies in 2012 and 2013 around the Koka Reservoir, Ethiopia. The results uncover the importance of reservoir management especially after the rainy seasons. Furthermore, we show the capability of a newly modified hydrology, entomology and malaria transmission simulator, HYDREMATS (Bomblies et al, 2008), and its potential as a tool for evaluating environmental management strategies to control malaria. HYDREMATS was developed to represent how the hydrology in nearby villages is impacted by the reservoir system, and the role of different types of vector ecologies associated with different Anopheles mosquito species. The hydrology component of HYDREMATS simulates three different mosquito breeding habitats: rain-fed pools, groundwater pools, and shoreline water. The entomology component simulates the life cycles of An. funestus and An. arabiensis, the two main vectors around the reservoir. The model was calibrated over the 2012-2013 period. The impact of reservoir water level management on the mosquito population is explored based on numerical model simulations and field experiments.

  19. Larval Temperature–Food Effects on Adult Mosquito Infection and Vertical Transmission of Dengue-1 Virus

    PubMed Central

    Buckner, Eva A.; Alto, Barry W.; Lounibos, L. Philip

    2016-01-01

    Temperature–food interactions in the larval environment can affect life history and population growth of container mosquitoes Aedes aegypti (L.) and Aedes albopictus Skuse, the primary vectors of chikungunya and dengue viruses. We used Ae. aegypti, Ae. albopictus, and dengue-1 virus (DENV-1) from Florida to investigate whether larval rearing temperature can alter the effects of larval food levels on Ae. aegypti and Ae. albopictus life history and DENV-1 infection and vertical transmission. Although we found no effect of larval treatments on survivorship to adulthood, DENV-1 titer, or DENV-1 vertical transmission, rates of vertical transmission up to 16–24% were observed in Ae. albopictus and Ae. aegypti, which may contribute to maintenance of this virus in nature. Larval treatments had no effect on number of progeny and DENV-1 infection in Ae. aegypti, but the interaction between temperature and food affected number of progeny and DENV-1 infection of the female Ae. albopictus parent. The cooler temperature (24°C) yielded the most progeny and this effect was accentuated by high food relative to the other conditions. Low and high food led to the highest (∼90%) and lowest (∼65%) parental infection at the cooler temperature, respectively, whereas intermediate infection rates (∼75–80%) were observed for all food conditions at the elevated temperature. These results suggest that temperature and food availability have minimal influence on rate of vertical transmission and a stronger influence on adults of Ae. albopictus than of Ae. aegypti, which could have consequences for dengue virus epidemiology. PMID:26489999

  20. Residual Efficacy of Field-Applied Permethrin, d-Phenothrin, and Resmethrin on Plant Foliage Against Adult Mosquitoes

    DTIC Science & Technology

    2008-01-01

    mortality (24 h) of mosquitoes in test cages placed within the vegetation. At 48 h and 1 wk posttreatment, insecticide treatments resulted in 70–100...reduction of adult mosquitoes caught by Centers for Disease Control and Prevention traps baited with 1-octen-3-ol. Insecticide residues in excised...duration of ,48 h postapplication, with residual effects dropping significantly thereafter. Average insecticide concentrations in leaves were quantified

  1. Population structure of the mosquito Aedes aegypti (Stegomyia aegypti) in Pakistan.

    PubMed

    Rasheed, S B; Boots, M; Frantz, A C; Butlin, R K

    2013-12-01

    Eleven microsatellite markers were used to determine the genetic population structure and spread of Aedes aegypti (Stegomyia aegypti) (Diptera: Culicidae) in Pakistan using mosquitoes collected from 13 different cities. There is a single genetic cluster of Ae. aegypti in Pakistan with a pattern of isolation by distance within the population. The low level of isolation by distance suggests the long-range passive dispersal of this mosquito, which may be facilitated by the tyre trade in Pakistan. A decrease in genetic diversity from south to north suggests a recent spread of this mosquito from Karachi. A strong negative correlation between genetic distance and the quality of road connections shows that populations in cities connected by better road networks are less differentiated, which suggests the human-aided passive dispersal of Ae. aegypti in Pakistan. Dispersal on a large spatial scale may facilitate the strategy of introducing transgenic Ae. aegypti or intracellular bacteria such as Wolbachia to control the spread of dengue disease in Pakistan, but it also emphasizes the need for simple measures to control container breeding sites.

  2. Risk assessment for adult butterflies exposed to the mosquito control pesticide naled

    USGS Publications Warehouse

    Bargar, Timothy A.

    2012-01-01

    A prospective risk assessment was conducted for adult butterflies potentially exposed to the mosquito control insecticide naled. Published acute mortality data, exposure data collected during field studies, and morphometric data (total surface area and fresh body weight) for adult butterflies were combined in a probabilistic estimate of the likelihood that adult butterfly exposure to naled following aerial applications would exceed levels associated with acute mortality. Adult butterfly exposure was estimated based on the product of (1) naled residues on samplers and (2) an exposure metric that normalized total surface area for adult butterflies to their fresh weight. The likelihood that the 10th percentile refined effect estimate for adult butterflies exposed to naled would be exceeded following aerial naled applications was 67 to 80%. The greatest risk would be for butterflies in the family Lycaenidae, and the lowest risk would be for those in the family Hesperidae, assuming equivalent sensitivity to naled. A range of potential guideline naled deposition levels is presented that, if not exceeded, would reduce the risk of adult butterfly mortality. The results for this risk assessment were compared with other risk estimates for butterflies, and the implications for adult butterflies in areas targeted by aerial naled applications are discussed.

  3. Risk assessment for adult butterflies exposed to the mosquito control pesticide naled.

    PubMed

    Bargar, Timothy A

    2012-04-01

    A prospective risk assessment was conducted for adult butterflies potentially exposed to the mosquito control insecticide naled. Published acute mortality data, exposure data collected during field studies, and morphometric data (total surface area and fresh body weight) for adult butterflies were combined in a probabilistic estimate of the likelihood that adult butterfly exposure to naled following aerial applications would exceed levels associated with acute mortality. Adult butterfly exposure was estimated based on the product of (1) naled residues on samplers and (2) an exposure metric that normalized total surface area for adult butterflies to their fresh weight. The likelihood that the 10th percentile refined effect estimate for adult butterflies exposed to naled would be exceeded following aerial naled applications was 67 to 80%. The greatest risk would be for butterflies in the family Lycaenidae, and the lowest risk would be for those in the family Hesperidae, assuming equivalent sensitivity to naled. A range of potential guideline naled deposition levels is presented that, if not exceeded, would reduce the risk of adult butterfly mortality. The results for this risk assessment were compared with other risk estimates for butterflies, and the implications for adult butterflies in areas targeted by aerial naled applications are discussed.

  4. Reduced size and starvation resistance in adult mosquitoes, Aedes notoscriptus, exposed to predation cues as larvae.

    PubMed

    van Uitregt, Vincent O; Hurst, Timothy P; Wilson, Robbie S

    2012-01-01

    1. Many prey organisms exhibit adaptive phenotypic plasticity in life-history traits that facilitate a better chance of survival in the presence of predators. The evolution of such plastic traits requires that the defensive phenotype incurs a cost in the absence of predation. 2. Model systems that are used to examine predator-induced defences are often organisms with complex life histories that only induce defences during the larval stage. While many studies have detected costs of inducible defences during the larval stage, detecting the costs of larval defences after metamorphosis is also important. 3. We examine the benefits and costs of inducible larval defences in the urban mosquito, Aedes notoscriptus, by rearing them in the presence and absence of predation cues. We compared survival of larvae inducing behavioural defences, when exposed to predation cues, in predation trials with predatory fish Hypseleotris galii to that of larvae reared in the absence predation cues. We also compared life-history traits of predator-exposed larvae to larvae reared in control conditions. 4. Larvae exposed to chemical predation cues limited activity and were able to avoid predation for longer in trials with H. galii. However, predator-exposed larvae suffered retarded larval growth and development, were smaller at metamorphosis and less resistant to starvation as adults. 5. While it is difficult to understand the 'fitness costs' that poorer starvation resistance might confer to adult mosquitoes, it is likely that smaller adult size of predator-exposed individuals would reduce fitness, particularly for females where body size limits the size of blood meal they could take to facilitate egg production. We suggest that the demonstrable costs of inducible defences in mosquito larvae make this a good system for testing theoretical models for the evolutionary maintenance of adaptive phenotypic plasticity.

  5. Larval nutritional stress affects vector immune traits in adult yellow fever mosquito Aedes aegypti (Stegomyia aegypti).

    PubMed

    Telang, A; Qayum, A A; Parker, A; Sacchetta, B R; Byrnes, G R

    2012-09-01

    We report key physiological traits that link larval nutritional experience to adult immune status in the yellow fever mosquito Aedes aegypti L. (Stegomyia aegypti) (Diptera: Culicidae). Many lines of defence make up the innate immune system of mosquitoes. Among defences, the epithelium-lined midgut is the first barrier, circulating haemocytes are cellular components of innate immunity and, when triggered, the Toll and Imd pathways signal production of antimicrobial peptides (AMP) as part of humoral defences. We quantified three lines of defence in Ae. aegypti in response to larval nutritional stress, and our data show that important female immune functions are modified by the larval rearing environment. Adult midgut basal lamina thickness was not affected by larval nutrient stress as has been observed in another Aedes sp. However, nutrient stresses experienced by larvae lead to a reduced number of haemocytes in females. Transcripts of Spaetzle (upstream regulator of Toll pathway that leads to induction of AMPs) and some immune-related genes were less abundant in stressed larvae but showed increased expression in females derived from stressed larvae. Results indicate a potential for compensation by the humoral branch for a reduced cellular branch of innate immunity in adults in response to larval nutrient stress.

  6. Ammonium sulphate fertiliser increases larval populations of Anopheles arabiensis and culicine mosquitoes in rice fields.

    PubMed

    Mutero, C M; Ng'ang'a, P N; Wekoyela, P; Githure, J; Konradsen, F

    2004-01-01

    Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block, and the fertiliser and control treatments allocated randomly among the ponds. Student's two-sample unpaired t-test was used to test for the significance of differences between the relative counts of larvae in fertiliser and control treatments. The results showed a significant overall increase in the larval populations of An. arabiensis (P<0.01) and culicine mosquitoes (P<0.05), after ponds were treated with the fertiliser. Significantly more fourth instar larvae of An. arabiensis were collected in fertiliser than control plots (P<0.001). An. arabiensis data indicated that the first fertiliser application had the most impact, compared to the second and third applications. This was evident in a significant peak of combined first and second instar An. arabiensis larvae observed 5 days after the first fertiliser application (P<0.05). The studies suggest that ammonium sulphate fertiliser reduces turbidity of water in rice fields, thereby making them visually more attractive for egg-laying by An. arabiensis and culicine mosquitoes.

  7. Impact of population age structure on Wolbachia transgene driver efficacy: ecologically complex factors and release of genetically modified mosquitoes.

    PubMed

    Rasgon, Jason L; Scott, Thomas W

    2004-07-01

    Wolbachia symbionts hold theoretical promise as a way to drive transgenes into insect vector populations for disease prevention. For simplicity, current models of Wolbachia dynamics and spread ignore ecologically complex factors such as the age structure of vector populations and overlapping vector generations. We developed a model including these factors to assess their impact on the process of Wolbachia spread into populations of three mosquito species (Anopheles gambiae, Aedes aegypti and Culex pipiens). Depending on the mosquito species, Wolbachia parameters, released mosquito life stage and initial age structure of the target population, the number of Wolbachia-infected mosquitoes that we predict would need to be released ranged from less than the threshold calculated by the simple model to a 10-30-fold increase. Transgenic releases into age-structured populations, which is an expectation for wild mosquitoes, will be difficult and depending on the circumstances may not be economically or logistically feasible due to the large number of infected mosquitoes that must be released. Our results support the perspective that understanding ecological factors is critical for designing transgenic vector-borne disease control strategies.

  8. Mathematical model of temephos resistance in Aedes aegypti mosquito population

    NASA Astrophysics Data System (ADS)

    Aldila, D.; Nuraini, N.; Soewono, E.; Supriatna, A. K.

    2014-03-01

    Aedes aegypti is the main vector of dengue disease in many tropical and sub-tropical countries. Dengue became major public concern in these countries due to the unavailability of vaccine or drugs for dengue disease in the market. Hence, the only way to control the spread of DF and DHF is by controlling the vectors carrying the disease, for instance with fumigation, temephos or genetic manipulation. Many previous studies conclude that Aedes aegypti may develop resistance to many kind of insecticide, including temephos. Mathematical model for transmission of temephos resistance in Aedes aegypti population is discussed in this paper. Nontrivial equilibrium point of the system and the corresponding existence are shown analytically. The model analysis have shown epidemiological trends condition that permits the coexistence of nontrivial equilibrium is given analytically. Numerical results are given to show parameter sensitivity and some cases of worsening effect values for illustrating possible conditions in the field.

  9. Environmental fate model for ultra-low-volume insecticide applications used for adult mosquito management

    USGS Publications Warehouse

    Schleier, Jerome J.; Peterson, Robert K.D.; Irvine, Kathryn M.; Marshall, Lucy M.; Weaver, David K.; Preftakes, Collin J.

    2012-01-01

    One of the more effective ways of managing high densities of adult mosquitoes that vector human and animal pathogens is ultra-low-volume (ULV) aerosol applications of insecticides. The U.S. Environmental Protection Agency uses models that are not validated for ULV insecticide applications and exposure assumptions to perform their human and ecological risk assessments. Currently, there is no validated model that can accurately predict deposition of insecticides applied using ULV technology for adult mosquito management. In addition, little is known about the deposition and drift of small droplets like those used under conditions encountered during ULV applications. The objective of this study was to perform field studies to measure environmental concentrations of insecticides and to develop a validated model to predict the deposition of ULV insecticides. The final regression model was selected by minimizing the Bayesian Information Criterion and its prediction performance was evaluated using k-fold cross validation. Density of the formulation and the density and CMD interaction coefficients were the largest in the model. The results showed that as density of the formulation decreases, deposition increases. The interaction of density and CMD showed that higher density formulations and larger droplets resulted in greater deposition. These results are supported by the aerosol physics literature. A k-fold cross validation demonstrated that the mean square error of the selected regression model is not biased, and the mean square error and mean square prediction error indicated good predictive ability.

  10. Applications of a sugar-based surveillance system to track arboviruses in wild mosquito populations.

    PubMed

    van den Hurk, Andrew F; Hall-Mendelin, Sonja; Townsend, Michael; Kurucz, Nina; Edwards, Jim; Ehlers, Gerhard; Rodwell, Chris; Moore, Frederick A; McMahon, Jamie L; Northill, Judith A; Simmons, Russell J; Cortis, Giles; Melville, Lorna; Whelan, Peter I; Ritchie, Scott A

    2014-01-01

    Effective arbovirus surveillance is essential to ensure the implementation of control strategies, such as mosquito suppression, vaccination, or dissemination of public warnings. Traditional strategies employed for arbovirus surveillance, such as detection of virus or virus-specific antibodies in sentinel animals, or detection of virus in hematophagous arthropods, have limitations as an early-warning system. A system was recently developed that involves collecting mosquitoes in CO2-baited traps, where the insects expectorate virus on sugar-baited nucleic acid preservation cards. The cards are then submitted for virus detection using molecular assays. We report the application of this system for detecting flaviviruses and alphaviruses in wild mosquito populations in northern Australia. This study was the first to employ nonpowered passive box traps (PBTs) that were designed to house cards baited with honey as the sugar source. Overall, 20/144 (13.9%) of PBTs from different weeks contained at least one virus-positive card. West Nile virus Kunjin subtype (WNVKUN), Ross River virus (RRV), and Barmah Forest virus (BFV) were detected, being identified in 13/20, 5/20, and 2/20 of positive PBTs, respectively. Importantly, sentinel chickens deployed to detect flavivirus activity did not seroconvert at two Northern Territory sites where four PBTs yielded WNVKUN. Sufficient WNVKUN and RRV RNA was expectorated onto some of the honey-soaked cards to provide a template for gene sequencing, enhancing the utility of the sugar-bait surveillance system for investigating the ecology, emergence, and movement of arboviruses.

  11. Persistent oscillations and backward bifurcation in a malaria model with varying human and mosquito populations: implications for control.

    PubMed

    Ngonghala, Calistus N; Teboh-Ewungkem, Miranda I; Ngwa, Gideon A

    2015-06-01

    We derive and study a deterministic compartmental model for malaria transmission with varying human and mosquito populations. Our model considers disease-related deaths, asymptomatic immune humans who are also infectious, as well as mosquito demography, reproduction and feeding habits. Analysis of the model reveals the existence of a backward bifurcation and persistent limit cycles whose period and size is determined by two threshold parameters: the vectorial basic reproduction number Rm, and the disease basic reproduction number R0, whose size can be reduced by reducing Rm. We conclude that malaria dynamics are indeed oscillatory when the methodology of explicitly incorporating the mosquito's demography, feeding and reproductive patterns is considered in modeling the mosquito population dynamics. A sensitivity analysis reveals important control parameters that can affect the magnitudes of Rm and R0, threshold quantities to be taken into consideration when designing control strategies. Both Rm and the intrinsic period of oscillation are shown to be highly sensitive to the mosquito's birth constant λm and the mosquito's feeding success probability pw. Control of λm can be achieved by spraying, eliminating breeding sites or moving them away from human habitats, while pw can be controlled via the use of mosquito repellant and insecticide-treated bed-nets. The disease threshold parameter R0 is shown to be highly sensitive to pw, and the intrinsic period of oscillation is also sensitive to the rate at which reproducing mosquitoes return to breeding sites. A global sensitivity and uncertainty analysis reveals that the ability of the mosquito to reproduce and uncertainties in the estimations of the rates at which exposed humans become infectious and infectious humans recover from malaria are critical in generating uncertainties in the disease classes.

  12. Ecdysis triggering hormone ensures proper timing of juvenile hormone biosynthesis in pharate adult mosquitoes.

    PubMed

    Areiza, Maria; Nouzova, Marcela; Rivera-Perez, Crisalejandra; Noriega, Fernando G

    2014-11-01

    Juvenile hormones (JHs) are synthesized by the corpora allata (CA) and play a key role in insect development. A decrease of JH titer in the last instar larvae allows pupation and metamorphosis to proceed. As the anti-metamorphic role of JH comes to an end, the CA of the late pupa (or pharate adult) becomes again "competent" to synthesize JH, which would play an essential role orchestrating reproductive maturation. In the present study, we provide evidence that ecdysis triggering hormone (ETH), a key endocrine factor involved in ecdysis control, acts as an allatotropic regulator of JH biosynthesis, controlling the exact timing of CA activation in the pharate adult mosquito. Analysis of the expression of Aedes aegypti ETH receptors (AeaETHRs) revealed that they are present in the CA and the corpora cardiaca (CC), and their expression peaks 4 h before eclosion. In vitro stimulation of the pupal CA glands with ETH resulted in an increase in JH synthesis. Consistent with this finding, silencing AeaETHRs by RNA interference (RNAi) in pupa resulted in reduced JH synthesis by the CA of one day-old adult females. Stimulation with ETH resulted in increases in the activity of juvenile hormone acid methyltransferase (JHAMT), a key JH biosynthetic enzyme. Furthermore, inhibition of IP3R-operated mobilization of endoplasmic reticulum Ca(2+) stores prevented the ETH-dependent increases of JH biosynthesis and JHAMT activity. All together these findings provide compelling evidence that ETH acts as a regulatory peptide that ensures proper developmental timing of JH synthesis in pharate adult mosquitoes.

  13. Effects of natal habitat odour, reinforced by adult experience, on choice of oviposition site in the mosquito Aedes aegypti.

    PubMed

    Hamilton, C E; Beresford, D V; Sutcliffe, J F

    2011-12-01

    The effects of natal experience on the oviposition behaviour of adult female mosquitoes were investigated in the laboratory using Aedes aegypti (L.) (Diptera: Culicidae). 'Treatment' mosquitoes were exposed to a dilute repellent (inducing stimulus) in their breeding water (aquatic stages) and/or in the air (adults) during various combinations of life stages [larval only (L regime); larval and pupal (LP regime); larval, pupal and emergent adult (LPE regime); larval, pupal, emergent adult and adult (LPEA regime); pupal, emergent adult and adult (PEA regime); adult only (A regime)]. 'Control' mosquitoes were raised in an identical manner, but were not exposed to the inducing stimulus. The oviposition behaviour of treatment and control females was assessed in an oviposition assay that presented a choice of water with or without the inducing stimulus. Of the 435 mosquitoes tested in the experiment, 176 were non-distributors (i.e. laid all of their eggs in only one of the choices). Treatment females (distributors plus non-distributors) reared in the presence of the inducing stimulus throughout their lives (LPEA regime) showed a significant preference for the oviposition option containing the inducing stimulus (24/36 females) compared with corresponding controls (5/39 females). Distributors reared under the LPEA and PEA regimes also showed this preference (6/6 treatment vs. 2/29 control females, and 13/18 treatment vs. 7/23 control females, respectively). Females that had been exposed to the inducing stimulus as either immatures or adults only showed no preference for, and some showed an aversion to, the treatment oviposition option. This is interpreted as evidence for a natal habitat preference induction (NHPI) in this species, albeit one that requires extensive reinforcement in the adult stage. This adult experience-reinforced NHPI (AER-NHPI) is discussed in terms of its adaptive significance for container breeders, the possible timing mechanism and sensory basis of

  14. Mosquito-producing containers, spatial distribution, and relationship between Aedes aegypti population indices on the southern boundary of its distribution in South America (Salto, Uruguay).

    PubMed

    Basso, César; Caffera, Ruben M; García da Rosa, Elsa; Lairihoy, Rosario; González, Cristina; Norbis, Walter; Roche, Ingrid

    2012-12-01

    A study was conducted in the city of Salto, Uruguay, to identify mosquito-producing containers, the spatial distribution of mosquitoes and the relationship between the different population indices of Aedes aegypti. On each of 312 premises visited, water-filled containers and immature Ae. aegypti mosquitoes were identified. The containers were counted and classified into six categories. Pupae per person and Stegomyia indices were calculated. Pupae per person were represented spatially. The number of each type of container and number of mosquitoes in each were analyzed and compared, and their spatial distribution was analyzed. No significant differences in the number of the different types of containers with mosquitoes or in the number of mosquitoes in each were found. The distribution of the containers with mosquito was random and the distribution of mosquitoes by type of container was aggregated or highly aggregated.

  15. Mosquito-Producing Containers, Spatial Distribution, and Relationship between Aedes aegypti Population Indices on the Southern Boundary of its Distribution in South America (Salto, Uruguay)

    PubMed Central

    Basso, César; Caffera, Ruben M.; García da Rosa, Elsa; Lairihoy, Rosario; González, Cristina; Norbis, Walter; Roche, Ingrid

    2012-01-01

    A study was conducted in the city of Salto, Uruguay, to identify mosquito-producing containers, the spatial distribution of mosquitoes and the relationship between the different population indices of Aedes aegypti. On each of 312 premises visited, water-filled containers and immature Ae. aegypti mosquitoes were identified. The containers were counted and classified into six categories. Pupae per person and Stegomyia indices were calculated. Pupae per person were represented spatially. The number of each type of container and number of mosquitoes in each were analyzed and compared, and their spatial distribution was analyzed. No significant differences in the number of the different types of containers with mosquitoes or in the number of mosquitoes in each were found. The distribution of the containers with mosquito was random and the distribution of mosquitoes by type of container was aggregated or highly aggregated. PMID:23128295

  16. Seasonal population dynamics and the genetic structure of the mosquito vector Aedes aegypti in São Paulo, Brazil

    PubMed Central

    Campos, Melina; Spenassatto, Carine; Lourdes da Graça Macoris, Maria; Paduan, Karina dos Santos; Pinto, João; Ribolla, Paulo Eduardo Martins

    2012-01-01

    Population genetic studies of insect vectors can generate knowledge to improve epidemiological studies focused on the decrease of pathogen transmission. In this study, we used nine SNPs across the Aedes aegypti genome to characterize seasonal population variations of this important dengue vector. Mosquito samples were obtained by ovitraps placed over Botucatu SP from 2005 to 2010. Our data show that, regardless of the large variation in mosquito abundance (deduced from the number of eggs obtained from ovitraps), the effective population size remained stable over the years. These results suggest that Ae. aegypti is able to maintain a sufficiently large active breeding population during the dry season to keep genetic frequencies stable. These results open new perspectives on mosquito survey and control methods. PMID:23170214

  17. [Progress on transgenic mosquitoes].

    PubMed

    Yang, Pin

    2011-04-30

    The genetically modified mosquitoes have been developed aiming to control mosquito-borne diseases by either reducing population sizes or replacing existing populations with vectors unable to transmit the disease. introduces some progress on the generation of transgenic mosquitoes and their fitness in wild population. This paper

  18. Multiple Wolbachia determinants control the evolution of cytoplasmic incompatibilities in Culex pipiens mosquito populations.

    PubMed

    Atyame, Celestine M; Duron, Olivier; Tortosa, Pablo; Pasteur, Nicole; Fort, Philippe; Weill, Mylene

    2011-01-01

    Wolbachia are maternally inherited endosymbionts that can invade arthropod populations through manipulation of their reproduction. In mosquitoes, Wolbachia induce embryonic death, known as cytoplasmic incompatibility (CI), whenever infected males mate with females either uninfected or infected with an incompatible strain. Although genetic determinants of CI are unknown, a functional model involving the so-called mod and resc factors has been proposed. Natural populations of Culex pipiens mosquito display a complex CI relationship pattern associated with the highest Wolbachia (wPip) genetic polymorphism reported so far. We show here that C. pipiens populations from La Réunion, a geographically isolated island in the southwest of the Indian Ocean, are infected with genetically closely related wPip strains. Crossing experiments reveal that these Wolbachia are all mutually compatible. However, crosses with genetically more distant wPip strains indicate that Wolbachia strains from La Réunion belong to at least five distinct incompatibility groups (or crossing types). These incompatibility properties which are strictly independent from the nuclear background, formally establish that in C. pipiens, CI is controlled by several Wolbachia mod/resc factors.

  19. Anopheles gambiae densovirus (AgDNV) has negligible effects on adult survival and transcriptome of its mosquito host.

    PubMed

    Ren, Xiaoxia; Hughes, Grant L; Niu, Guodong; Suzuki, Yasutsugu; Rasgon, Jason L

    2014-01-01

    Mosquito densoviruses (DNVs) are candidate agents for paratransgenic control of malaria and other vector-borne diseases. Unlike other mosquito DNVs, the Anopheles gambiae DNV (AgDNV) is non-pathogenic to larval mosquitoes. However, the cost of infection upon adults and the molecular mechanisms underpinning infection in the mosquito host are unknown. Using life table analysis, we show that AgDNV infection has minimal effects on An. gambiae survival (no significant effect in 2 replicates and a slight 2 day survival decrease in the third replicate). Using microarrays, we show that AgDNV has very minimal effect on the adult mosquito transcriptome, with only 4-15 genes differentially regulated depending on the statistical criteria imposed. The minimal impact upon global transcription provides some mechanistic understanding of lack of virus pathogenicity, suggesting a long co-evolutionary history that has shifted towards avirulence. From an applied standpoint, lack of strong induced fitness costs makes AgDNV an attractive agent for paratransgenic malaria control.

  20. Anopheles gambiae densovirus (AgDNV) has negligible effects on adult survival and transcriptome of its mosquito host

    PubMed Central

    Niu, Guodong; Suzuki, Yasutsugu

    2014-01-01

    Mosquito densoviruses (DNVs) are candidate agents for paratransgenic control of malaria and other vector-borne diseases. Unlike other mosquito DNVs, the Anopheles gambiae DNV (AgDNV) is non-pathogenic to larval mosquitoes. However, the cost of infection upon adults and the molecular mechanisms underpinning infection in the mosquito host are unknown. Using life table analysis, we show that AgDNV infection has minimal effects on An. gambiae survival (no significant effect in 2 replicates and a slight 2 day survival decrease in the third replicate). Using microarrays, we show that AgDNV has very minimal effect on the adult mosquito transcriptome, with only 4–15 genes differentially regulated depending on the statistical criteria imposed. The minimal impact upon global transcription provides some mechanistic understanding of lack of virus pathogenicity, suggesting a long co-evolutionary history that has shifted towards avirulence. From an applied standpoint, lack of strong induced fitness costs makes AgDNV an attractive agent for paratransgenic malaria control. PMID:25279264

  1. Larval and adult nutrition effects on blood/nectar choice of Culex nigripalpus mosquitoes.

    PubMed

    Hancock, R G; Foster, W A

    1997-04-01

    The impact of nutritional variables on the development of host-seeking and biting behaviours after emergence by female Culex nigripalpus mosquitoes were studied using air-flow olfactometer and close-range biting assays, respectively. Unfed females failed to develop resting stage ovarian follicles. When offered a bird host in the absence of competing stimuli, sugar-fed mosquitoes were significantly more responsive in both host-seeking and biting than unfed controls. In a choice olfactometer assay using nectar odours (honey scented with artificial apple-blossom oil) versus host odours (a bird), unfed females preferred honey over bird odours except when honey odour was weak. After sucrose feeding, females switched from honey to bird preference. This change in behaviour was accompanied by significant accumulation of lipid and by follicular growth to the resting stage. Elevation of host responsiveness after sugar feeding was reversible; starvation ultimately resulted in females preferring honey over bird odours. When the larval diet was restricted by crowding, the wing-length and total lipid of resultant adult females were reduced. Although differences were subtle, unfed bird-responding females tended to have longer wings and more lipid than their honey-responding counterparts.

  2. Entomopathogenic fungi for mosquito control: A review

    PubMed Central

    Scholte, Ernst-Jan; Knols, Bart G.J.; Samson, Robert A.; Takken, Willem

    2004-01-01

    Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti) curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis. PMID:15861235

  3. Transient population dynamics of mosquitoes during sterile male releases: modelling mating behaviour and perturbations of life history parameters.

    PubMed

    Stone, Christopher M

    2013-01-01

    The release of genetically-modified or sterile male mosquitoes offers a promising form of mosquito-transmitted pathogen control, but the insights derived from our understanding of male mosquito behaviour have not fully been incorporated into the design of such genetic control or sterile-male release methods. The importance of aspects of male life history and mating behaviour for sterile-male release programmes were investigated by projecting a stage-structured matrix model over time. An elasticity analysis of transient dynamics during sterile-male releases was performed to provide insight on which vector control methods are likely to be most synergistic. The results suggest that high mating competitiveness and mortality costs of released males are required before the sterile-release method becomes ineffective. Additionally, if released males suffer a mortality cost, older males should be released due to their increased mating capacity. If released males are of a homogenous size and size-assortative mating occurs in nature, this can lead to an increase in the abundance of large females and reduce the efficacy of the population-suppression effort. At a high level of size-assortative mating, the disease transmission potential of the vector population increases due to male releases, arguing for the release of a heterogeneously-sized male population. The female population was most sensitive to perturbations of density-dependent components of larval mortality and female survivorship and fecundity. These findings suggest source reduction might be a particularly effective complement to mosquito control based on the sterile insect technique (SIT). In order for SIT to realize its potential as a key component of an integrated vector-management strategy to control mosquito-transmitted pathogens, programme design of sterile-male release programmes must account for the ecology, behaviour and life history of mosquitoes. The model used here takes a step in this direction and can

  4. Repellent, Irritant and Toxic Effects of 20 Plant Extracts on Adults of the Malaria Vector Anopheles gambiae Mosquito

    PubMed Central

    Deletre, Emilie; Martin, Thibaud; Campagne, Pascal; Bourguet, Denis; Cadin, Andy; Menut, Chantal; Bonafos, Romain; Chandre, Fabrice

    2013-01-01

    Pyrethroid insecticides induce an excito-repellent effect that reduces contact between humans and mosquitoes. Insecticide use is expected to lower the risk of pathogen transmission, particularly when impregnated on long-lasting treated bednets. When applied at low doses, pyrethroids have a toxic effect, however the development of pyrethroid resistance in several mosquito species may jeopardize these beneficial effects. The need to find additional compounds, either to kill disease-carrying mosquitoes or to prevent mosquito contact with humans, therefore arises. In laboratory conditions, the effects (i.e., repellent, irritant and toxic) of 20 plant extracts, mainly essential oils, were assessed on adults of Anopheles gambiae, a primary vector of malaria. Their effects were compared to those of DEET and permethrin, used as positive controls. Most plant extracts had irritant, repellent and/or toxic effects on An. gambiae adults. The most promising extracts, i.e. those combining the three types of effects, were from Cymbopogon winterianus, Cinnamomum zeylanicum and Thymus vulgaris. The irritant, repellent and toxic effects occurred apparently independently of each other, and the behavioural response of adult An. gambiae was significantly influenced by the concentration of the plant extracts. Mechanisms underlying repellency might, therefore, differ from those underlying irritancy and toxicity. The utility of the efficient plant extracts for vector control as an alternative to pyrethroids may thus be envisaged. PMID:24376515

  5. Bioinsecticide and leaf litter combination increases oviposition and reduces adult recruitment to create an effective ovitrap for Culex mosquitoes.

    PubMed

    Bellile, Katie G; Vonesh, James R

    2016-06-01

    Mosquito egg traps, aquatic habitats baited with oviposition attractant and insecticide, are important tools for surveillance and control efforts in integrated vector management programs. The bioinsecticide Bacillus thuringiensis subsp. israelensis (Bti) is increasingly used as an environmentally friendly alternative to chemical insecticides and the combination of Bti with a simple oviposition attractant like leaf litter to create an effective egg trap seems appealing. However, previous research suggests that Bti may itself alter oviposition, and that leaf litter may dramatically reduce Bti toxicity. Here we present results from field experiment designed to link the effects of litter and Bti on mosquito oviposition habitat selection and post-colonization survival to production of adult mosquitoes. Tripling litter increased Culex spp. oviposition nearly nine-fold, while Bti had no effect on oviposition. Neither factor altered egg survival, thus larval abundance reflected the effects of litter on oviposition. Both Bti and litter reduced larval survival by ∼60%. We found no evidence that increased litter reduced Bti toxicity. Adult production was dependent upon both litter and Bti. In the absence of Bti, effects of litter on oviposition translated into three-fold more adults. However, in the presence of Bti, initial increases in oviposition were erased by the combined negative effects of Bti and litter on post-colonization survival. Thus, our study provides field evidence that combined litter and Bti application creates an effective ovitrap. This combined treatment had the highest oviposition and the lowest survival, and thus removed the greatest number of mosquitoes from the landscape.

  6. Environmentally friendly tool to control mosquito populations without risk of insecticide resistance: the Lehmann’s funnel entry trap

    PubMed Central

    2013-01-01

    Background Current malaria control strategies have cut down the malaria burden in many endemic areas, however the emergence and rapid spread of insecticide and drug resistance undermine the success of these efforts. There is growing concern that malaria eradication will not be achieved without the introduction of novel control tools. One approach that has been developed in the last few years is based on house screening to reduce indoor mosquito vector densities and consequently decrease malaria transmission. Here screening and trapping were combined in one tool to control mosquito populations. The trap does not require an insecticide or even an attractant, yet it effectively collects incoming resistant and susceptible mosquitoes and kills them. Results Performance of the funnel entry trap was tested in low and high malaria vector density areas. An overall reduction of 70 to 80% of mosquito density was seen in both. Species and molecular forms of Anopheles gambiae identification indicated no variation in the number of Anopheles arabiensis and the molecular forms of An. gambiae between houses and traps. Mosquitoes collected in the traps and in houses were highly resistant to pyrethroids (0.9 kdr-based mechanism). Conclusion There is a global consensus that new intervention tools are needed to cross the last miles in malaria elimination/eradication. The funnel entry trap showed excellent promise in suppressing mosquito densities even in area of high insecticide resistance. It requires no chemicals and is self-operated. PMID:23758904

  7. Chikungunya virus susceptibility & variation in populations of Aedes aegypti (Diptera: Culicidae) mosquito from India

    PubMed Central

    Gokhale, Mangesh D.; Paingankar, Mandar S.; Sudeep, Anakathil B.; Parashar, Deepti

    2015-01-01

    Background & objectives: Although having immense clinical relevance, yet only a few studies have been targeted to understand the chikungunya virus (CHIKV) susceptibility and growth in Aedes aegypti populations from India. This study was undertaken to investigate CHIKV susceptibility and growth kinetics in Ae. aegypti along with genetic heterogeneity of Ae. aegypti populations. Methods: Dose dependent CHIKV susceptibility and growth kinetic studies for three CHIKV strains reported from India were carried out in Ae. aegypti mosquito populations. The phenotypic variation and genetic heterogeneity in five Ae. aegypti populations were investigated using multivariate morphometrics and allozyme variation studies. Results: The dissemination and growth kinetics studies of the three CHIKV strains showed no selective advantage for a particular strain of CHIKV in Ae. aegypti. At 100 per cent infection rate, five geographic Ae. aegypti populations showed differences in dissemination to three CHIKV strains. Morphometric studies revealed phenotypic variation in all the studied populations. The allelic frequencies, F statistics, and Nei's genetic identity values showed that genetic differences between the populations were small, but significant. Interpretation & conclusions: The results obtained in this study suggest that genetic background of the vector strongly influences the CHIKV susceptibility in Ae. aegypti. PMID:26905240

  8. Elevated couch potato transcripts associated with adult diapause in the mosquito Culex pipiens.

    PubMed

    Zhang, Qirui; Denlinger, David L

    2011-05-01

    The couch potato (cpo) cDNA that we cloned from the northern house mosquito, Culex pipiens, encodes the C-terminus containing a highly conserved RNA recognition motif (RRM). Protein structure prediction indicates a canonical RRM structure with a βαββαβ topological structure. Northern blots indicate a single mRNA band over 9.49 kb, and Southern blot analysis suggests that the cpo gene contains large introns. Highest expression was noted in first instar larvae and pupae. A comparison of nondiapausing (long daylength) and diapausing (short daylength) adult females showed no difference immediately at adult eclosion, but by day 7 and thereafter, expression of cpo was much higher in diapausing adults. When 2-month old diapausing females were transferred from short daylength to diapausing-terminating conditions of long daylength and high temperature, expression of cpo declined. Similarly, when a topical application of JH III was used to terminate diapause abundance of the cpo transcript declined. Consistent with observations in Drosophila melanogaster and several other species levels of cpo in C. pipiens are influenced by the diapause program, although the direction of change is not the same in all species.

  9. Genetic Variations in Bionomics of Culex quinquefasciatus (Diptera: Culicidae) Mosquito Population in Minna, North Central Nigeria

    PubMed Central

    Ukubuiwe, Azubuike C.; Olayemi, Israel K.; Jibrin, Aisha I.

    2016-01-01

    The need to have an improved knowledge on the bioecology of Culex quinquefasciatus, a prerequisite in the development of cost-effective control strategies, has informed the present preliminary investigation to put in better perspective variations that exist in the egg rafts of the species. Freshly laid egg rafts were collected and incubated at ambient temperature in well-labeled plastic trays. The results showed overall inconsistency in all indices monitored for the egg rafts. Generally, survivorship was high for the species. All immature stage and adult parameters measured varied significantly among the egg rafts and between/within sexes of the species. Therefore, this study suggests the presence of inherent variation in the bionomics of egg rafts of C. quinquefasciatus, probably influenced by the environment and hence underscores the need for additional studies to further elucidate the roles of genetics and environment in vectorial competence of the species, in order to develop robust sustainable mosquito vector control protocols. PMID:27013900

  10. Temporal gene expression profiles of pre blood-fed adult females Immediately following eclosion in the southern house mosquito culex quinquefasciatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior to acquisition of the first host blood meal, the anautogenous mosquito Culex quinquefasciatus requires a period of time in order to prepare for the blood feeding and, later, vitellogenesis. In the current study, we conducted whole transcriptome analyses of adult female Culex mosquitoes to iden...

  11. Detection, monitoring, and evaluation of spatio-temporal change in mosquito populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    USDA-ARS scientists seek to implement a sampling and global information technology based system that can be used for mosquito detection and trap deployment, to estimate mosquito species composition and distribution in space and time, and for targeting and evaluation of mosquito controls. Knowledge ...

  12. A Tale of Two City Blocks: Differences in Immature and Adult Mosquito Abundances between Socioeconomically Different Urban Blocks in Baltimore (Maryland, USA)

    PubMed Central

    Becker, Brian; Leisnham, Paul T.; LaDeau, Shannon L.

    2014-01-01

    Infrastructure degradation in many post-industrial cities has increased the availability of potential mosquito habitats, including container habitats that support infestations of invasive disease-vectors. This study is unique in examining both immature and adult mosquito abundance across the fine-scale variability in socio-economic condition that occurs block-to-block in many cities. We hypothesized that abundant garbage associated with infrastructure degradation would support greater mosquito production but instead, found more mosquito larvae and host-seeking adults (86%) in parcels across the higher socio-economic, low-decay block. Aedes albopictus and Culex pipiens were 5.61 (p < 0.001) and 4.60 (p = 0.001) times more abundant, respectively. Most discarded (garbage) containers were dry during peak mosquito production, which occurred during the 5th hottest July on record. Containers associated with human residence were more likely to hold water and contain immature mosquitoes. We propose that mosquito production switches from rain-fed unmanaged containers early in the season to container habitats that are purposefully shaded or watered by mid-season. This study suggests that residents living in higher socioeconomic areas with low urban decay may be at greater risk of mosquito-borne disease during peak mosquito production when local container habitats are effectively decoupled from environmental constraints. PMID:24651396

  13. Guidelines to site selection for population surveillance and mosquito control trials: a case study from Mauritius.

    PubMed

    Iyaloo, Diana P; Elahee, Khouaildi B; Bheecarry, Ambicadutt; Lees, Rosemary Susan

    2014-04-01

    Many novel approaches to controlling mosquito vectors through the release of sterile and mass reared males are being developed in the face of increasing insecticide resistance and other limitations of current methods. Before full scale release programmes can be undertaken there is a need for surveillance of the target population, and investigation of parameters such as dispersal and longevity of released, as compared to wild males through mark-release-recapture (MRR) and other experiments, before small scale pilot trials can be conducted. The nature of the sites used for this field work is crucial to ensure that a trial can feasibly collect sufficient and relevant information, given the available resources and practical limitations, and having secured the correct regulatory, community and ethical approvals and support. Mauritius is considering the inclusion of the sterile insect technique (SIT), for population reduction of Aedes albopictus, as a component of the Ministry of Health and Quality of Life's 'Operational Plan for Prevention and Control of Chikungunya and Dengue'. As part of an investigation into the feasibility of integrating the SIT into the Integrated Vector Management (IVM) scheme in Mauritius a pilot trial is planned. Two potential sites have been selected for this purpose, Pointe des Lascars and Panchvati, villages in the North East of the country, and population surveillance has commenced. This case study will here be used to explore the considerations which go into determining the most appropriate sites for mosquito field research. Although each situation is unique, and an ideal site may not be available, this discussion aims to help researchers to consider and balance the important factors and select field sites that will meet their needs.

  14. Satellite vegetation index data as a tool to forecast population dynamics of medically important mosquitoes at military installations in the continental United States.

    PubMed

    Britch, Seth C; Linthicum, Kenneth J; Anyamba, Assaf; Tucker, Compton J; Pak, Edwin W; Maloney, Francis A; Cobb, Kristin; Stanwix, Erin; Humphries, Jeri; Spring, Alexandra; Pagac, Benedict; Miller, Melissa

    2008-07-01

    The United States faces many existing and emerging mosquito-borne disease threats, such as West Nile virus and Rift Valley fever. An important component of strategic prevention and control plans for these and other mosquito-borne diseases is forecasting the distribution, timing, and abundance of mosquito vector populations. Populations of many medically important mosquito species are closely tied to climate, and historical climate-population associations may be used to predict future population dynamics. Using 2003-2005 U.S. Army Center for Health Promotion and Preventive Medicine mosquito surveillance data, we looked at populations of several known mosquito vectors of West Nile virus, as well as possible mosquito vectors of Rift Valley fever virus, at continental U.S. military installations. We compared population changes with concurrent patterns for a satellite-derived index of climate (normalized difference vegetation index) and observed instances of population changes appearing to be direct responses to climate. These preliminary findings are important first steps in developing an automated, climate-driven, early warning system to flag regions of the United States at elevated risk of mosquito-borne disease transmission.

  15. Pathways of expansion and multiple introductions illustrated by large genetic differentiation among worldwide populations of the southern house mosquito.

    PubMed

    Fonseca, Dina M; Smith, Julie L; Wilkerson, Richard C; Fleischer, Robert C

    2006-02-01

    The southern house mosquito Culex quinquefasciatus is a principal vector of human lymphatic filariasis, several encephalitides (including West Nile virus), avian malaria, and poxvirus, but its importance as a vector varies considerably among regions. This species has spread with humans and is ubiquitous in tropical urban and suburban environments. This was the first mosquito to reach Hawaii and we performed a worldwide genetic survey using micro-satellite loci to identify its source. Our analyses showed divergent Old World and New World genetic signatures in Cx. quinquefasciatus with further distinctions between east and west African, Asian, and Pacific populations that correlate with the epidemiology of human filariasis. We found that in Hawaii south Pacific mosquitoes have largely replaced the original New World introduction of Cx. quinquefasciatus, consistent with their reported expansion to higher elevations. We hypothesize worldwide pathways of expansion of this disease vector.

  16. New tools for surveillance of adult yellow fever mosquitoes: comparison of trap catches with human landing rates in an urban environment.

    PubMed

    Krockel, Ulla; Rose, Andreas; Eiras, Alvaro E; Geier, Martin

    2006-06-01

    A novel mosquito trapping system, the BG-Sentinel trap, was evaluated as a monitoring tool for adult Aedes aegypti in field tests in the city of Belo Horizonte, Brazil. Human landing/biting collections, a gas-powered CO2 trap, and a Fay-Prince trap with only visual cues serving as references to evaluate the efficacy of the new trap. The BG-Sentinel is a simple suction trap that uses upward-directed air currents as well as visual cues to attract mosquitoes. The trap was tested with a new dispenser system (BG-Lure) that releases artificial human skin odors and needs no CO2. In comparison with the two other traps, the BG-Sentinel caught significantly more Ae. aegypti. Although human landing rates were the highest, there was no significant difference between human landing rates and the capture rates of the BG-Sentinel trap. The finding indicates that the trap can be considered as an acceptable alternative to human landing/biting collections in the surveillance of adult host-seeking dengue vectors. The addition of BG-Lure to the gas-powered CO2 trap greatly increased its efficacy. This combination, however, was not significantly more effective than the BG-Sentinel without CO2. In a 6-month comparison between the BG-Sentinel and a sticky ovitrap for gravid females, the BG-Sentinel proved to be a far more efficient and sensitive tool to measure the density of Ae. aegypti populations.

  17. Adult height, nutrition, and population health

    PubMed Central

    Perkins, Jessica M.; Subramanian, S.V.; Davey Smith, George

    2016-01-01

    In this review, the potential causes and consequences of adult height, a measure of cumulative net nutrition, in modern populations are summarized. The mechanisms linking adult height and health are examined, with a focus on the role of potential confounders. Evidence across studies indicates that short adult height (reflecting growth retardation) in low- and middle-income countries is driven by environmental conditions, especially net nutrition during early years. Some of the associations of height with health and social outcomes potentially reflect the association between these environmental factors and such outcomes. These conditions are manifested in the substantial differences in adult height that exist between and within countries and over time. This review suggests that adult height is a useful marker of variation in cumulative net nutrition, biological deprivation, and standard of living between and within populations and should be routinely measured. Linkages between adult height and health, within and across generations, suggest that adult height may be a potential tool for monitoring health conditions and that programs focused on offspring outcomes may consider maternal height as a potentially important influence. PMID:26928678

  18. Adult height, nutrition, and population health.

    PubMed

    Perkins, Jessica M; Subramanian, S V; Davey Smith, George; Özaltin, Emre

    2016-03-01

    In this review, the potential causes and consequences of adult height, a measure of cumulative net nutrition, in modern populations are summarized. The mechanisms linking adult height and health are examined, with a focus on the role of potential confounders. Evidence across studies indicates that short adult height (reflecting growth retardation) in low- and middle-income countries is driven by environmental conditions, especially net nutrition during early years. Some of the associations of height with health and social outcomes potentially reflect the association between these environmental factors and such outcomes. These conditions are manifested in the substantial differences in adult height that exist between and within countries and over time. This review suggests that adult height is a useful marker of variation in cumulative net nutrition, biological deprivation, and standard of living between and within populations and should be routinely measured. Linkages between adult height and health, within and across generations, suggest that adult height may be a potential tool for monitoring health conditions and that programs focused on offspring outcomes may consider maternal height as a potentially important influence.

  19. Comparison of Model Predictions and Laboratory Observations of Transgene Frequencies in Continuously-Breeding Mosquito Populations

    PubMed Central

    Valerio, Laura; North, Ace; Collins, C. Matilda; Mumford, John D.; Facchinelli, Luca; Spaccapelo, Roberta; Benedict, Mark Q.

    2016-01-01

    The persistence of transgenes in the environment is a consideration in risk assessments of transgenic organisms. Combining mathematical models that predict the frequency of transgenes and experimental demonstrations can validate the model predictions, or can detect significant biological deviations that were neither apparent nor included as model parameters. In order to assess the correlation between predictions and observations, models were constructed to estimate the frequency of a transgene causing male sexual sterility in simulated populations of a malaria mosquito Anopheles gambiae that were seeded with transgenic females at various proportions. Concurrently, overlapping-generation laboratory populations similar to those being modeled were initialized with various starting transgene proportions, and the subsequent proportions of transgenic individuals in populations were determined weekly until the transgene disappeared. The specific transgene being tested contained a homing endonuclease gene expressed in testes, I-PpoI, that cleaves the ribosomal DNA and results in complete male sexual sterility with no effect on female fertility. The transgene was observed to disappear more rapidly than the model predicted in all cases. The period before ovipositions that contained no transgenic progeny ranged from as little as three weeks after cage initiation to as long as 11 weeks. PMID:27669312

  20. Comparison of Model Predictions and Laboratory Observations of Transgene Frequencies in Continuously-Breeding Mosquito Populations.

    PubMed

    Valerio, Laura; North, Ace; Collins, C Matilda; Mumford, John D; Facchinelli, Luca; Spaccapelo, Roberta; Benedict, Mark Q

    2016-09-22

    The persistence of transgenes in the environment is a consideration in risk assessments of transgenic organisms. Combining mathematical models that predict the frequency of transgenes and experimental demonstrations can validate the model predictions, or can detect significant biological deviations that were neither apparent nor included as model parameters. In order to assess the correlation between predictions and observations, models were constructed to estimate the frequency of a transgene causing male sexual sterility in simulated populations of a malaria mosquito Anopheles gambiae that were seeded with transgenic females at various proportions. Concurrently, overlapping-generation laboratory populations similar to those being modeled were initialized with various starting transgene proportions, and the subsequent proportions of transgenic individuals in populations were determined weekly until the transgene disappeared. The specific transgene being tested contained a homing endonuclease gene expressed in testes, I-PpoI, that cleaves the ribosomal DNA and results in complete male sexual sterility with no effect on female fertility. The transgene was observed to disappear more rapidly than the model predicted in all cases. The period before ovipositions that contained no transgenic progeny ranged from as little as three weeks after cage initiation to as long as 11 weeks.

  1. Response of adult mosquitoes to light emitting diodes placed in resting boxes and in the field.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resting boxes are passive devices used to attract and capture mosquitoes seeking shelter. Increasing the attractiveness of these devices could improve their effectiveness. Light emitting diodes (LEDs) can be attractive to mosquitoes when used together with other trapping devices. Therefore restin...

  2. Field evaluation of boric acid and fipronil based bait stations against adult mosquitoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effectiveness of boric acid (1%) and fipronil (0.1%) bait stations in reducing the number of laboratory-reared female Aedes aegypti and Ochlerotatus taeniorhynchus mosquitoes released in outdoor screened cages was evaluated. Both toxicants reduced landing rates of the two mosquito species on a ...

  3. Stable coexistence of incompatible Wolbachia along a narrow contact zone in mosquito field populations.

    PubMed

    Atyame, Célestine M; Labbé, Pierrick; Rousset, François; Beji, Marwa; Makoundou, Patrick; Duron, Olivier; Dumas, Emilie; Pasteur, Nicole; Bouattour, Ali; Fort, Philippe; Weill, Mylène

    2015-01-01

    In arthropods, the intracellular bacteria Wolbachia often induce cytoplasmic incompatibility (CI) between sperm and egg, which causes conditional embryonic death and promotes the spatial spread of Wolbachia infections into host populations. The ability of Wolbachia to spread in natural populations through CI has attracted attention for using these bacteria in vector-borne disease control. The dynamics of incompatible Wolbachia infections have been deeply investigated theoretically, whereas in natural populations, there are only few examples described, especially among incompatible infected hosts. Here, we have surveyed the distribution of two molecular Wolbachia strains (wPip11 and wPip31) infecting the mosquito Culex pipiens in Tunisia. We delineated a clear spatial structure of both infections, with a sharp contact zone separating their distribution areas. Crossing experiments with isofemale lines from different localities showed three crossing types: wPip11-infected males always sterilize wPip31-infected females; however, while most wPip31-infected males were compatible with wPip11-infected females, a few completely sterilize them. The wPip11 strain was thus expected to spread, but temporal dynamics over 7 years of monitoring shows the stability of the contact zone. We examined which factors may contribute to the observed stability, both theoretically and empirically. Population cage experiments, field samples and modelling did not support significant impacts of local adaptation or assortative mating on the stability of wPip infection structure. By contrast, low dispersal probability and metapopulation dynamics in the host Cx. pipiens probably play major roles. This study highlights the need of understanding CI dynamics in natural populations to design effective and sustainable Wolbachia-based control strategies.

  4. Geographic Variation in Adult Survival and Reproductive Tactics of the Mosquito Aedes albopictus

    PubMed Central

    LEISNHAM, P. T.; SALA, L. M.; JULIANO, S. A.

    2008-01-01

    Climate differences across latitude can result in seasonal constraints and selection on life history characters. Since Aedes albopictus (Skuse) invaded North America in the mid-1980s, it has spread across a range of ≈14° latitude and populations in the north experience complete adult mortality due to cold winter temperatures that are absent in the south. Life table experiments were conducted to test for differences in the adult survival and reproductive schedules of Ae. albopictus females from two populations from the northern (Bloomington, IN [BL] and Manassas, VA [VA]; ≈39° N) and southern (Tampa, FL and Fort Myers, FL; ≈27–28° N) extremes of the species distribution in North America. Regardless of population origin, age-specific hazard rate increased with reproductive output and decreased with number of bloodmeals. Larger females took fewer bloodmeals, and they had greater hazard rates than did smaller females. There were no consistent differences between northern versus southern populations in resource allocation between reproduction and maintenance, reproduction over time, and reproductive investment among offspring, suggesting that latitudinal variation in climate is probably not a main selective factor impinging on adult mortality and reproductive schedules. One possible effect of climate on geographic differences in life history was detected. BL had lower survivorship, lower lifetime reproductive output, and lower adult reproductive rate than did all other populations. This result may be an indirect result of lower egg survivorship due to the severity of winter in BL compared with other populations, including VA at approximately the same latitude. Such a scenario may make the BL population more prone to extinction, irregularly recolonized from more favorable sites, and thus more susceptible to founder effects, genetic drift, and inbreeding, resulting in lower mean values of fitness-related traits. PMID:18402136

  5. Effects of wind speed on aerosol spray penetration in adult mosquito bioassay cages.

    PubMed

    Hoffmann, W Clint; Fritz, Bradley K; Farooq, Muhammad; Cooperband, Miriam F

    2008-09-01

    Bioassay cages are commonly used to assess efficacy of insecticides against adult mosquitoes in the field. To correlate adult mortality readings to insecticidal efficacy and/or spray application parameters properly, it is important to know how the cage used in the bioassay interacts with the spray cloud containing the applied insecticide. This study compared the size of droplets, wind speed, and amount of spray material penetrating cages and outside of cages in a wind tunnel at different wind speeds. Two bioassay cages, Center for Medical, Agricultural and Veterinary Entomology (CMAVE) and Circle, were evaluated. The screen materials used on these cages reduced the size of droplets, wind speed, and amount of spray material inside the cages as compared to the spray cloud and wind velocity outside of the cages. When the wind speed in the dispersion tunnel was set at 0.6 m/sec (1.3 mph), the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.045 m/sec (0.10 mph) and 0.075 m/sec (0.17 mph), respectively. At air velocities of 2.2 m/sec (4.9 mph) in the dispersion tunnel, the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.83 m/sec (1.86 mph) and 0.71 m/sec (1.59 mph), respectively. Consequently, there was a consistent 50-70% reduction of spray material penetrating the cages compared to the spray cloud that approached the cages. These results provide a better understanding of the impact of wind speed, cage design, and construction on ultra-low-volume spray droplets.

  6. Population genetics of the Asian tiger mosquito Aedes albopictus, an invasive vector of human diseases.

    PubMed

    Goubert, C; Minard, G; Vieira, C; Boulesteix, M

    2016-09-01

    The Asian tiger mosquito Aedes albopictus is currently one of the most threatening invasive species in the world. Native to Southeast Asia, the species has spread throughout the world in the past 30 years and is now present in every continent but Antarctica. Because it was the main vector of recent Dengue and Chikungunya outbreaks, and because of its competency for numerous other viruses and pathogens such as the Zika virus, A. albopictus stands out as a model species for invasive diseases vector studies. A synthesis of the current knowledge about the genetic diversity of A. albopictus is needed, knowing the interplays between the vector, the pathogens, the environment and their epidemiological consequences. Such resources are also valuable for assessing the role of genetic diversity in the invasive success. We review here the large but sometimes dispersed literature about the population genetics of A. albopictus. We first debate about the experimental design of these studies and present an up-to-date assessment of the available molecular markers. We then summarize the main genetic characteristics of natural populations and synthesize the available data regarding the worldwide structuring of the vector. Finally, we pinpoint the gaps that remain to be addressed and suggest possible research directions.

  7. Population genetics of the Asian tiger mosquito Aedes albopictus, an invasive vector of human diseases

    PubMed Central

    Goubert, C; Minard, G; Vieira, C; Boulesteix, M

    2016-01-01

    The Asian tiger mosquito Aedes albopictus is currently one of the most threatening invasive species in the world. Native to Southeast Asia, the species has spread throughout the world in the past 30 years and is now present in every continent but Antarctica. Because it was the main vector of recent Dengue and Chikungunya outbreaks, and because of its competency for numerous other viruses and pathogens such as the Zika virus, A. albopictus stands out as a model species for invasive diseases vector studies. A synthesis of the current knowledge about the genetic diversity of A. albopictus is needed, knowing the interplays between the vector, the pathogens, the environment and their epidemiological consequences. Such resources are also valuable for assessing the role of genetic diversity in the invasive success. We review here the large but sometimes dispersed literature about the population genetics of A. albopictus. We first debate about the experimental design of these studies and present an up-to-date assessment of the available molecular markers. We then summarize the main genetic characteristics of natural populations and synthesize the available data regarding the worldwide structuring of the vector. Finally, we pinpoint the gaps that remain to be addressed and suggest possible research directions. PMID:27273325

  8. Estimation of Aedes aegypti (Diptera: Culicidae) population size and adult male survival in an urban area in Panama.

    PubMed

    Neira, Marco; Lacroix, Renaud; Cáceres, Lorenzo; Kaiser, Paul E; Young, Josue; Pineda, Lleysa; Black, Isaac; Sosa, Nestor; Nimmo, Derric; Alphey, Luke; McKemey, Andrew

    2014-11-01

    Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®), rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i) establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b) estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86). Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha), which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed.

  9. Estimation of Aedes aegypti (Diptera: Culicidae) population size and adult male survival in an urban area in Panama

    PubMed Central

    Neira, Marco; Lacroix, Renaud; Cáceres, Lorenzo; Kaiser, Paul E; Young, Josue; Pineda, Lleysa; Black, Isaac; Sosa, Nestor; Nimmo, Derric; Alphey, Luke; McKemey, Andrew

    2014-01-01

    Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®), rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i) establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b) estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86). Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha), which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed. PMID:25410991

  10. Novel estimates of Aedes aegypti (Diptera: Culicidae) population size and adult survival based on Wolbachia releases.

    PubMed

    Ritchie, Scott A; Montgomery, Brian L; Hoffmann, Ary A

    2013-05-01

    The size of Aedes aegypti (L.) mosquito populations and adult survival rates have proven difficult to estimate because of a lack of consistent quantitative measures to equate sampling methods, such as adult trapping, to actual population size. However, such estimates are critical for devising control methods and for modeling the transmission of dengue and other infectious agents carried by this species. Here we take advantage of recent releases of Wolbachia-infected Ae. aegypti coupled with the results of ongoing monitoring to estimate the size of adult Ae. aegypti populations around Cairns in far north Queensland, Australia. Based on the association between released adults infected with Wolbachia and data from Biogents Sentinel traps, we show that data from two locations are consistent with population estimates of approximately 5-10 females per house and daily survival rates of 0.7-0.9 for the released Wolbachia-infected females. Moreover, we estimate that networks of Biogents Sentinel traps at a density of one per 15 houses capture around 5-10% of the adult population per week, and provide a rapid estimate of the absolute population size of Ae. aegypti. These data are discussed with respect to release rates and monitoring in future Wolbachia releases and also the levels of suppression required to reduce dengue transmission.

  11. Comparisons of mosquito populations before and after construction of a wetland for water quality improvement in Pitt County, North Carolina, and data-reliant vectorborne disease management.

    PubMed

    Anderson, Alice L; O'Brien, Kevin; Hartwell, Megan

    2007-04-01

    Wetlands serve an important purpose in flood control and water quality, but constructed-wetland sites also provide habitats for mosquito breeding. Communities near constructed-wetland sites often raise a "mosquito" objection when constructed wetlands are proposed. Wildlife and wetland advocates can confuse the public by making unsubstantiated claims about natural predators eliminating or controlling mosquito problems in a constructed wetland. Management of constructed-wetland mosquito habitat, with adequate mosquito surveillance and data analysis, can help lead to a successful project and satisfied citizens. The cooperative project described in this paper, was conducted in the town of Simpson, North Carolina, and was designed to determine the mosquito population impact of wetland construction at Mill Branch Stream, a small tributary of the Tar River in Eastern North Carolina. In the authors' analysis of three years of mosquito surveillance data, month (time of year standing in for temperature and day length) was a significant factor in regression analysis for mosquito numbers, but rainfall was not. Numbers of mosquitoes were not found to be significantly higher after construction than before construction.

  12. Molecular characterization of Chikungunya virus isolates from clinical samples and adult Aedes albopictus mosquitoes emerged from larvae from Kerala, South India.

    PubMed

    Niyas, Kudukkil P; Abraham, Rachy; Unnikrishnan, Ramakrishnan Nair; Mathew, Thomas; Nair, Sajith; Manakkadan, Anoop; Issac, Aneesh; Sreekumar, Easwaran

    2010-08-13

    Chikungunya virus (CHIKV), an arthritogenic alphavirus, is transmitted to humans by infected Aedes (Ae.) aegypti and Ae.albopictus mosquitoes. In the study, reverse-transcription PCR (RT PCR) and virus isolation detected CHIKV in patient samples and also in adult Ae.albopictus mosquitoes that was derived from larvae collected during a chikungunya (CHIK) outbreak in Kerala in 2009. The CHIKV strains involved in the outbreak were the East, Central and South African (ECSA) genotype that had the E1 A226V mutation. The viral strains from the mosquitoes and CHIK patients from the same area showed a close relationship based on phylogenetic analysis. Genetic characterization by partial sequencing of non-structural protein 2 (nsP2; 378 bp), envelope E1 (505 bp) and E2 (428 bp) identified one critical mutation in the E2 protein coding region of these CHIKV strains. This novel, non-conservative mutation, L210Q, consistently present in both human and mosquito-derived samples studied, was within the region of the E2 protein (amino acids E2 200-220) that determines mosquito cell infectivity in many alpha viruses. Our results show the involvement of Ae. albopictus in this outbreak in Kerala and appearance of CHIKV with novel genetic changes. Detection of virus in adult mosquitoes, emerged in the laboratory from larvae, also points to the possibility of transovarial transmission (TOT) of mutant CHIKV strains in mosquitoes.

  13. RNAi-mediated gene knockdown and in vivo diuresis assay in adult female Aedes aegypti mosquitoes.

    PubMed

    Drake, Lisa L; Price, David P; Aguirre, Sarah E; Hansen, Immo A

    2012-07-14

    This video protocol demonstrates an effective technique to knockdown a particular gene in an insect and conduct a novel bioassay to measure excretion rate. This method can be used to obtain a better understanding of the process of diuresis in insects and is especially useful in the study of diuresis in blood-feeding arthropods that are able to take up huge amounts of liquid in a single blood meal. This RNAi-mediated gene knockdown combined with an in vivo diuresis assay was developed by the Hansen lab to study the effects of RNAi-mediated knockdown of aquaporin genes on Aedes aegypti mosquito diuresis. The protocol is setup in two parts: the first demonstration illustrates how to construct a simple mosquito injection device and how to prepare and inject dsRNA into the thorax of mosquitoes for RNAi-mediated gene knockdown. The second demonstration illustrates how to determine excretion rates in mosquitoes using an in vivo bioassay.

  14. Population pharmacokinetics of micafungin in adult patients.

    PubMed

    Gumbo, Tawanda; Hiemenz, John; Ma, Lei; Keirns, James J; Buell, Donald N; Drusano, George L

    2008-03-01

    We performed population pharmacokinetic analysis of micafungin in adult patients treated with doses between 12.5 and 200 mg/day. Our analysis identified a breakpoint patient weight of 66.3 kg above which serum clearance increased by approximately 50%. Patients with weight >66.3 kg may need larger doses to achieve similar exposures to those <66.3 kg. However, the clinical implications are still unknown.

  15. Bacterial Communities and Midgut Microbiota Associated with Mosquito Populations from Waste Tires in East-Central Illinois.

    PubMed

    Kim, Chang-Hyun; Lampman, Richard L; Muturi, Ephantus J

    2015-01-01

    Mosquito-microbe interactions tend to influence larval nutrition, immunity, and development, as well as fitness and vectorial capacity of adults. Understanding the role of different bacterial species not only improves our knowledge of the physiological and ecological consequences of these interactions, but also provides the basis for developing novel strategies for controlling mosquito-borne diseases. We used culture-dependent and culture-independent techniques to characterize the bacterial composition and abundance in water and midgut samples of larval and adult females of Aedes japonicus (Theobald), Aedes triseriatus (Say), and Culex restuans (Theobald) collected from waste tires at two wooded study sites in Urbana, IL. The phylum-specific real-time quantitative polymerase chain reaction assay revealed a higher proportion of Actinobacteria and a lower proportion of gamma-Proteobacteria and Bacteroidetes in water samples and larval midguts compared to adult female midguts. Only 15 of the 57 bacterial species isolated in this study occurred in both study sites. The number of bacterial species was highest in water samples (28 species from Trelease Woods; 25 species from South Farms), intermediate in larval midguts (13 species from Ae. japonicus; 12 species from Ae. triseriatus; 8 species from Cx. restuans), and lowest in adult female midguts (2 species from Ae. japonicus; 3 species from Ae. triseriatus). These findings suggest that the composition and richness of bacterial communities varies both between habitats and among mosquito species and that the reduction in bacteria diversity during metamorphosis is more evident among bacteria detected using the culture-dependent method.

  16. Male Mosquitoes as Vehicles for Insecticide

    PubMed Central

    Mains, James W.; Brelsfoard, Corey L.; Dobson, Stephen L.

    2015-01-01

    Background The auto-dissemination approach has been shown effective at treating cryptic refugia that remain unaffected by existing mosquito control methods. This approach relies on adult mosquito behavior to spread larvicide to breeding sites at levels that are lethal to immature mosquitoes. Prior studies demonstrate that ‘dissemination stations,’ deployed in mosquito-infested areas, can contaminate adult mosquitoes, which subsequently deliver the larvicide to breeding sites. In some situations, however, preventative measures are needed, e.g., to mitigate seasonal population increases. Here we examine a novel approach that combines elements of autocidal and auto-dissemination strategies by releasing artificially reared, male mosquitoes that are contaminated with an insecticide. Methodology Laboratory and field experiments examine for model-predicted impacts of pyriproxyfen (PPF) directly applied to adult male Aedes albopictus, including (1) the ability of PPF-treated males to cross-contaminate females and to (2) deliver PPF to breeding sites. Principal Findings Similar survivorship was observed in comparisons of PPF-treated and untreated males. Males contaminated both female adults and oviposition containers in field cage tests, at levels that eliminated immature survivorship. Field trials demonstrate an ability of PPF-treated males to transmit lethal doses to introduced oviposition containers, both in the presence and absence of indigenous females. A decline in the Ae. albopictus population was observed following the introduction of PPF-treated males, which was not observed in two untreated field sites. Conclusions/Significance The results demonstrate that, in cage and open field trials, adult male Ae. albopictus can tolerate PPF and contaminate, either directly or indirectly, adult females and immature breeding sites. The results support additional development of the proposed approach, in which male mosquitoes act as vehicles for insecticide delivery

  17. Vertical Transmission of Zika Virus by Aedes aegypti and Ae. albopictus Mosquitoes.

    PubMed

    Ciota, Alexander T; Bialosuknia, Sean M; Ehrbar, Dylan J; Kramer, Laura D

    2017-05-15

    To determine the potential role of vertical transmission in Zika virus expansion, we evaluated larval pools of perorally infected Aedes. aegypti and Ae. albopictus adult female mosquitoes; ≈1/84 larvae tested were Zika virus-positive; and rates varied among mosquito populations. Thus, vertical transmission may play a role in Zika virus spread and maintenance.

  18. High Prevalence and Lineage Diversity of Avian Malaria in Wild Populations of Great Tits (Parus major) and Mosquitoes (Culex pipiens)

    PubMed Central

    Glaizot, Olivier; Fumagalli, Luca; Iritano, Katia; Lalubin, Fabrice; Van Rooyen, Juan; Christe, Philippe

    2012-01-01

    Avian malaria studies have taken a prominent place in different aspects of evolutionary ecology. Despite a recent interest in the role of vectors within the complex interaction system of the malaria parasite, they have largely been ignored in most epidemiological studies. Epidemiology of the disease is however strongly related to the vector's ecology and behaviour, and there is a need for basic investigations to obtain a better picture of the natural associations between Plasmodium lineages, vector species and bird hosts. The aim of the present study was to identify the mosquito species involved in the transmission of the haemosporidian parasites Plasmodium spp. in two wild populations of breeding great tits (Parus major) in western Switzerland. Additionally, we compared Plasmodium lineages, based on mitochondrial DNA cytochrome b sequences, between the vertebrate and dipteran hosts, and evaluated the prevalence of the parasite in the mosquito populations. Plasmodium spp. were detected in Culex pipiens only, with an overall 6.6% prevalence. Among the six cytochrome b lineages of Plasmodium identified in the mosquitoes, three were also present in great tits. The results provide evidence for the first time that C. pipiens can act as a natural vector of avian malaria in Europe and yield baseline data for future research on the epidemiology of avian malaria in European countries. PMID:22506060

  19. High prevalence and lineage diversity of avian malaria in wild populations of great tits (Parus major) and mosquitoes (Culex pipiens).

    PubMed

    Glaizot, Olivier; Fumagalli, Luca; Iritano, Katia; Lalubin, Fabrice; Van Rooyen, Juan; Christe, Philippe

    2012-01-01

    Avian malaria studies have taken a prominent place in different aspects of evolutionary ecology. Despite a recent interest in the role of vectors within the complex interaction system of the malaria parasite, they have largely been ignored in most epidemiological studies. Epidemiology of the disease is however strongly related to the vector's ecology and behaviour, and there is a need for basic investigations to obtain a better picture of the natural associations between Plasmodium lineages, vector species and bird hosts. The aim of the present study was to identify the mosquito species involved in the transmission of the haemosporidian parasites Plasmodium spp. in two wild populations of breeding great tits (Parus major) in western Switzerland. Additionally, we compared Plasmodium lineages, based on mitochondrial DNA cytochrome b sequences, between the vertebrate and dipteran hosts, and evaluated the prevalence of the parasite in the mosquito populations. Plasmodium spp. were detected in Culex pipiens only, with an overall 6.6% prevalence. Among the six cytochrome b lineages of Plasmodium identified in the mosquitoes, three were also present in great tits. The results provide evidence for the first time that C. pipiens can act as a natural vector of avian malaria in Europe and yield baseline data for future research on the epidemiology of avian malaria in European countries.

  20. Wolbachia-Based Population Control Strategy Targeting Culex quinquefasciatus Mosquitoes Proves Efficient under Semi-Field Conditions

    PubMed Central

    Atyame, Célestine M.; Cattel, Julien; Lebon, Cyrille; Flores, Olivier; Dehecq, Jean-Sébastien; Weill, Mylène; Gouagna, Louis Clément; Tortosa, Pablo

    2015-01-01

    In mosquitoes, the maternally inherited bacterial Wolbachia induce a form of embryonic lethality called cytoplasmic incompatibility (CI). This property can be used to reduce the density of mosquito field populations through inundative releases of incompatible males in order to sterilize females (Incompatible Insect Technique, or IIT, strategy). We have previously constructed the LR[wPip(Is)] line representing a good candidate for controlling field populations of the Culex quinquefasciatus mosquito in the islands of the south-western Indian Ocean. The main purpose of the present study was to fill the gap between laboratory experiments and field implementation, i.e. assessing mating competitiveness of these incompatible males under semi-field conditions. In a first set of experiments, we analyzed crossing relationships between LR[wPip(Is)] males and La Réunion field females collected as larvae in 19 distinct localities throughout the island. This investigation revealed total embryonic mortality, confirming the strong sterilizing capacity of LR[wPip(Is)] males. Subsequently, mating competitiveness of LR[wPip(Is)] males was assessed under semi-field conditions in the presence of field males and females from La Réunion. Confrontations were carried out in April and December using different ratios of LR[wPip(Is)] to field males. The results indicated that the LR[wPip(Is)] males successfully compete with field males in mating with field females, displaying even higher competitiveness than field males in April. Our results support the implementation of small-scale field tests in order to assess the feasibility of IIT against Cx. quinquefasciatus in the islands of southwestern Indian Ocean where this mosquito species is a proven competent vector for human pathogens. PMID:25768841

  1. Preventing Childhood Malaria in Africa by Protecting Adults from Mosquitoes with Insecticide-Treated Nets

    PubMed Central

    Killeen, Gerry F; Smith, Tom A; Ferguson, Heather M; Mshinda, Hassan; Abdulla, Salim; Lengeler, Christian; Kachur, Steven P

    2007-01-01

    Background Malaria prevention in Africa merits particular attention as the world strives toward a better life for the poorest. Insecticide-treated nets (ITNs) represent a practical means to prevent malaria in Africa, so scaling up coverage to at least 80% of young children and pregnant women by 2010 is integral to the Millennium Development Goals (MDG). Targeting individual protection to vulnerable groups is an accepted priority, but community-level impacts of broader population coverage are largely ignored even though they may be just as important. We therefore estimated coverage thresholds for entire populations at which individual- and community-level protection are equivalent, representing rational targets for ITN coverage beyond vulnerable groups. Methods and Findings Using field-parameterized malaria transmission models, we show that high (80% use) but exclusively targeted coverage of young children and pregnant women (representing <20% of the population) will deliver limited protection and equity for these vulnerable groups. In contrast, relatively modest coverage (35%–65% use, with this threshold depending on ecological scenario and net quality) of all adults and children, rather than just vulnerable groups, can achieve equitable community-wide benefits equivalent to or greater than personal protection. Conclusions Coverage of entire populations will be required to accomplish large reductions of the malaria burden in Africa. While coverage of vulnerable groups should still be prioritized, the equitable and communal benefits of wide-scale ITN use by older children and adults should be explicitly promoted and evaluated by national malaria control programmes. ITN use by the majority of entire populations could protect all children in such communities, even those not actually covered by achieving existing personal protection targets of the MDG, Roll Back Malaria Partnership, or the US President's Malaria Initiative. PMID:17608562

  2. A Longitudinal Analysis of Mosquito Net Ownership and Use in an Indigenous Batwa Population after a Targeted Distribution

    PubMed Central

    Clark, Sierra; Berrang-Ford, Lea; Lwasa, Shuaib; Namanya, Didacus; Twesigomwe, Sabastian; Kulkarni, Manisha

    2016-01-01

    Major efforts for malaria prevention programs have gone into scaling up ownership and use of insecticidal mosquito nets, particularly in sub-Saharan Africa where the malaria burden is high. Socioeconomic inequities in access to long lasting insecticidal nets (LLINs) are reduced with free distributions of nets. However, the relationship between social factors and retention of nets after a free distribution has been less studied, particularly using a longitudinal approach. Our research aimed to estimate the ownership and use of LLINs, and examine the determinants of LLIN retention, within an Indigenous Batwa population after a free LLIN distribution. Two LLINs were given free of charge to each Batwa household in Kanungu District, Uganda in November 2012. Surveyors collected data on LLIN ownership and use through six cross-sectional surveys pre- and post-distribution. Household retention, within household access, and individual use of LLINs were assessed over an 18-month period. Socioeconomic determinants of household retention of LLINs post-distribution were modelled longitudinally using logistic regression with random effects. Direct house-to-house distribution of free LLINs did not result in sustainable increases in the ownership and use of LLINs. Three months post-distribution, only 73% of households owned at least one LLIN and this period also saw the greatest reduction in ownership compared to other study periods. Eighteen-months post distribution, only a third of households still owned a LLIN. Self-reported age-specific use of LLINs was generally higher for children under five, declined for children aged 6–12, and was highest for older adults aged over 35. In the model, household wealth was a significant predictor of LLIN retention, controlling for time and other variables. This research highlights on-going socioeconomic inequities in access to malaria prevention measures among the Batwa in southwestern Uganda, even after free distribution of LLINs, and

  3. Using Stable Isotopes of Carbon and Nitrogen to Mark Wild Populations of Anopheles and Aedes Mosquitoes in South-Eastern Tanzania

    PubMed Central

    Opiyo, Mercy A.; Hamer, Gabriel L.; Lwetoijera, Dickson W.; Auckland, Lisa D.; Majambere, Silas; Okumu, Fredros O.

    2016-01-01

    Background Marking wild mosquitoes is important for understanding their ecology, behaviours and role in disease transmission. Traditional insect marking techniques include using fluorescent dyes, protein labels, radioactive labels and tags, but such techniques have various limitations; notably low marker retention and inability to mark wild mosquitoes at source. Stable isotopes are gaining wide spread use for non-invasive marking of arthropods, permitting greater understanding of mosquito dispersal and responses to interventions. We describe here a simple technique for marking naturally-breeding malaria and dengue vectors using stable isotopes of nitrogen (15N) and carbon (13C), and describe potential field applications. Methods We created man-made aquatic mosquito habitats and added either 15N-labelled potassium nitrate or 13C-labelled glucose, leaving non-adulterated habitats as controls. We then allowed wild mosquitoes to lay eggs in these habitats and monitored their development in situ. Pupae were collected promptly as they appeared and kept in netting cages. Emergent adults (in pools of ~4 mosquitoes/pool) and individually stored pupae were desiccated and analysed using Isotope Ratio Mass Spectrometry (IRMS). Findings Anopheles gambiae s.l and Aedes spp. from enriched 13C and enriched 15N larval habitats had significantly higher isotopic levels than controls (P = 0.005), and both isotopes produced sufficient distinction between marked and unmarked mosquitoes. Mean δ15N for enriched females and males were 275.6±65.1 and 248.0±54.6, while mean δ15N in controls were 2.1±0.1 and 3.9±1.7 respectively. Similarly, mean δ13C for enriched females and males were 36.08±5.28 and 38.5±6.86, compared to -4.3±0.2 and -7.9±3.6 in controls respectively. Mean δ15N and δ13C was significantly higher in any pool containing at least one enriched mosquito compared to pools with all unenriched mosquitoes, P<0.001. In all cases, there were variations in standardized

  4. Salivary Gland Proteome during Adult Development and after Blood Feeding of Female Anopheles dissidens Mosquitoes (Diptera: Culicidae)

    PubMed Central

    Phattanawiboon, Benjarat; Jariyapan, Narissara; Mano, Chonlada; Roytrakul, Sittiruk; Paemanee, Atchara; Sor-Suwan, Sriwatapron; Sriwichai, Patchara; Saeung, Atiporn; Bates, Paul A.

    2016-01-01

    Understanding changes in mosquito salivary proteins during the time that sporozoite maturation occurs and after blood feeding may give information regarding the roles of salivary proteins during the malarial transmission. Anopheles dissidens (formerly Anopheles barbirostris species A1) is a potential vector of Plasmodium vivax in Thailand. In this study, analyses of the proteomic profiles of female An. dissidens salivary glands during adult development and after blood feeding were carried out using two-dimensional gel electrophoresis coupled with nano-liquid chromatography-mass spectrometry. Results showed at least 17 major salivary gland proteins present from day one to day 21 post emergence at 8 different time points sampled. Although there was variation observed, the patterns of protein expression could be placed into one of four groups. Fifteen protein spots showed significant depletion after blood feeding with the percentages of the amount of depletion ranging from 8.5% to 68.11%. The overall results identified various proteins, including a putative mucin-like protein, an anti-platelet protein, a long form D7 salivary protein, a putative gVAG protein precursor, a D7-related 3.2 protein, gSG7 salivary proteins, and a gSG6 protein. These results allow better understanding of the changes of the salivary proteins during the adult mosquito development. They also provide candidate proteins to investigate any possible link or not between sporozoite maturation, or survival of skin stage sporozoites, and salivary proteins. PMID:27669021

  5. Chikungunya Virus 3′ Untranslated Region: Adaptation to Mosquitoes and a Population Bottleneck as Major Evolutionary Forces

    PubMed Central

    Chen, Rubing; Wang, Eryu; Tsetsarkin, Konstantin A.; Weaver, Scott C.

    2013-01-01

    The 3′ untranslated genome region (UTR) of arthropod-borne viruses is characterized by enriched direct repeats (DRs) and stem-loop structures. Despite many years of theoretical and experimental study, on-going positive selection on the 3′UTR had never been observed in ‘real-time,’ and the role of the arbovirus 3′UTR remains poorly understood. We observed a lineage-specific 3′UTR sequence pattern in all available Asian lineage of the mosquito-borne alphavirus, chikungunya virus (CHIKV) (1958–2009), including complicated mutation and duplication patterns of the long DRs. Given that a longer genome is usually associated with less efficient replication, we hypothesized that the fixation of these genetic changes in the Asian lineage 3′UTR was due to their beneficial effects on adaptation to vectors or hosts. Using reverse genetic methods, we examined the functional importance of each direct repeat. Our results suggest that adaptation to mosquitoes, rather than to mammalian hosts, is a major evolutionary force on the CHIKV 3′UTR. Surprisingly, the Asian 3′UTR appeared to be inferior to its predicted ancestral sequence for replication in both mammals and mosquitoes, suggesting that its fixation in Asia was not a result of directional selection. Rather, it may have resulted from a population bottleneck during its introduction from Africa to Asia. We propose that this introduction of a 3′UTR with deletions led to genetic drift and compensatory mutations associated with the loss of structural/functional constraints, followed by two independent beneficial duplications and fixation due to positive selection. Our results provide further evidence that the limited epidemic potential of the Asian CHIKV strains resulted from founder effects that reduced its fitness for efficient transmission by mosquitoes there. PMID:24009512

  6. Area-wide management of Aedes albopictus: choice of study sites based on geospatial characteristics, socioeconomic factors, and mosquito populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aedes (Stegomyia) albopictus (Skuse), the Asian tiger mosquito, is an introduced invasive species in the U.S. responsible for a significant proportion of service requests to local mosquito control programs. This container-utilizing mosquito is refractory to standard mosquito abatement measures in th...

  7. Genetic Diversity and Population Genetics of Mosquitoes (Diptera: Culicidae: Culex spp.) from the Sonoran Desert of North America

    PubMed Central

    Pfeiler, Edward; Flores-López, Carlos A.; Mada-Vélez, Jesús Gerardo; Escalante-Verdugo, Juan; Markow, Therese A.

    2013-01-01

    The population genetics and phylogenetic relationships of Culex mosquitoes inhabiting the Sonoran Desert region of North America were studied using mitochondrial DNA and microsatellite molecular markers. Phylogenetic analyses of mitochondrial cytochrome c oxidase subunit I (COI) from mosquitoes collected over a wide geographic area, including the Baja California peninsula, and mainland localities in southern Arizona, USA and Sonora, Mexico, showed several well-supported partitions corresponding to Cx. quinquefasciatus, Cx. tarsalis, and two unidentified species, Culex sp. 1 and sp. 2. Culex quinquefasciatus was found at all localities and was the most abundant species collected. Culex tarsalis was collected only at Tucson, Arizona and Guaymas, Sonora. The two unidentified species of Culex were most abundant at Navojoa in southern Sonora. Haplotype and nucleotide diversities in the COI gene segment were substantially lower in Cx. quinquefasciatus compared with the other three species. Analysis of molecular variance revealed little structure among seven populations of Cx. quinquefasciatus, whereas significant structure was found between the two populations of Cx. tarsalis. Evidence for an historical population expansion beginning in the Pleistocene was found for Cx. tarsalis. Possible explanations for the large differences in genetic diversity between Cx. quinquefasciatus and the other species of Culex are presented. PMID:24302868

  8. Climate-population analysis of potential mosquito vectors of emerging arbovirus disease threats to the US

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction Rift Valley fever (RVF) is a mosquito-borne hemorrhagic viral disease with substantial negative impacts on public and animal health in its endemic range of sub-Saharan Africa. Rift Valley fever virus (RVFV) could enter the United States and lead to widespread morbidity and mortality in ...

  9. French invasive Asian tiger mosquito populations harbor reduced bacterial microbiota and genetic diversity compared to Vietnamese autochthonous relatives

    PubMed Central

    Minard, G.; Tran, F. H.; Van, Van Tran; Goubert, C.; Bellet, C.; Lambert, G.; Kim, Khanh Ly Huynh; Thuy, Trang Huynh Thi; Mavingui, P.; Valiente Moro, C.

    2015-01-01

    The Asian tiger mosquito Aedes albopictus is one of the most significant pathogen vectors of the twenty-first century. Originating from Asia, it has invaded a wide range of eco-climatic regions worldwide. The insect-associated microbiota is now recognized to play a significant role in host biology. While genetic diversity bottlenecks are known to result from biological invasions, the resulting shifts in host-associated microbiota diversity has not been thoroughly investigated. To address this subject, we compared four autochthonous Ae. albopictus populations in Vietnam, the native area of Ae. albopictus, and three populations recently introduced to Metropolitan France, with the aim of documenting whether these populations display differences in host genotype and bacterial microbiota. Population-level genetic diversity (microsatellite markers and COI haplotype) and bacterial diversity (16S rDNA metabarcoding) were compared between field-caught mosquitoes. Bacterial microbiota from the whole insect bodies were largely dominated by Wolbachia pipientis. Targeted analysis of the gut microbiota revealed a greater bacterial diversity in which a fraction was common between French and Vietnamese populations. The genus Dysgonomonas was the most prevalent and abundant across all studied populations. Overall genetic diversities of both hosts and bacterial microbiota were significantly reduced in recently established populations of France compared to the autochthonous populations of Vietnam. These results open up many important avenues of investigation in order to link the process of geographical invasion to shifts in commensal and symbiotic microbiome communities, as such shifts may have dramatic impacts on the biology and/or vector competence of invading hematophagous insects. PMID:26441903

  10. Adult repellency and larvicidal activity of five plant essential oils against mosquitoes.

    PubMed

    Zhu, Junwei; Zeng, Xiaopeng; Yanma; Liu, Ting; Qian, Kuen; Han, Yuhua; Xue, Suqin; Tucker, Brad; Schultz, Gretchen; Coats, Joel; Rowley, Wayne; Zhang, Aijun

    2006-09-01

    The larvicidal activity and repellency of 5 plant essential oils--thyme oil, catnip oil, amyris oil, eucalyptus oil, and cinnamon oil--were tested against 3 mosquito species: Aedes albopictus, Ae. aegypti, and Culex pipiens pallens. Larvicidal activity of these essentials oils was evaluated in the laboratory against 4th instars of each of the 3 mosquito species, and amyris oil demonstrated the greatest inhibitory effect with LC50 values in 24 h of 58 microg/ml (LC90 = 72 microg/ml) for Ae. aegypti, 78 microg/ml (LC90 = 130 microg/ml) for Ae. albopictus, and 77 microg/ml (LC90 = 123 microg/ml) for Cx. p. pallens. The topical repellency of these selected essential oils and deet against laboratory-reared female blood-starved Ae. albopictus was examined. Catnip oil seemed to be the most effective and provided 6-h protection at both concentrations tested (23 and 468 microg/ cm2). Thyme oil had the highest effectiveness in repelling this species, but the repellency duration was only 2 h. The applications using these natural product essential oils in mosquito control are discussed.

  11. Comparison of mosquito (Diptera: Culicidae) populations by wetland type and year in the lower river Dalälven region, Central Sweden.

    PubMed

    Schäfer, M L; Lundström, J O; Petersson, E

    2008-06-01

    We studied adult mosquito assemblages in six wetlands, representing three types (wet meadow, alder swamp, and bog), in the lower part of the River Dalälven in Central Sweden during three consecutive years (2000-2002) and evaluated the influence of wetland type and year. Mosquito abundance differed significantly between years but not between wetland types. Mosquito species richness showed no significant variation between years or wetland types. Cluster analysis based on percentage of similarity resulted in three clusters, with high similarity between all wetlands in 2000. Ordination analysis showed that mosquito assemblages were mainly correlated with wetland type and water level increase in the previous month. Hydrological conditions varied between the years and between the wetland types, and our collections also included a year (2000) with extreme flood situations. The floodwater mosquito species Ochlerotatus sticticus was the predominant species with a strong influence on the whole study due to its long-range dispersal ability. The entire region suffered from enormous numbers of Oc. sticticus in 2000. The data from this study provided the basis for the initiation of a mosquito control project in the region.

  12. Aerial ULV application of permethrin against adult mosquitoes over open field and medium density canopy habitat in a hot-temperate zone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although aerial ULV application of adulticides is a common adult mosquito control strategy, not enough is known about the fate of the pesticide or its efficacy over different habitats. Dye labeling of droplets is used to evaluate ULV applications, and, by inference, their efficacy. Placement of cage...

  13. Comparative effectiveness of three adult mosquito sampling methods in habitats representative of four different biomes of California.

    PubMed

    Reisen, W K; Boyce, K; Cummings, R C; Delgado, O; Gutierrez, A; Meyer, R P; Scott, T W

    1999-03-01

    The effectiveness of New Jersey (NJ) light, dry ice baited, and gravid female traps for collecting adult mosquitoes was compared at representative habitats in the Coachella, San Joaquin, and Sacramento valleys and the Los Angeles basin of California. The NJ light traps effectively sampled Anopheles freeborni, Culex tarsalis, Psorophora columbiae, and several Aedes when abundance was high in rural areas with minimal competitive illumination. Dry ice-baited encephalitis virus surveillance or CDC style traps collected significantly more females of most species at most localities than did NJ light traps, regardless of background illumination. The Cummings modification of the Reiter gravid female trap baited with a bulrush (Schoenoplectus) infusion was the best method for collecting Culex pipiens complex females in most habitats. In the Los Angeles basin, gravid traps baited with bulrush infusion collected, on average, 4.5 times more Culex quinquefasciatus females than did traps baited with the Reiter infusion. The bulrush infusion in combination with the Cummings trap design seemed to provide resting site cues and collected males as well as empty and bloodfed females. Mosquito surveillance programs in California should include the systematic operation of dry ice-baited and gravid female traps to improve surveillance sensitivity for selected species in appropriate habitats.

  14. Climate-based models for West Nile Culex mosquito vectors in the Northeastern US

    NASA Astrophysics Data System (ADS)

    Gong, Hongfei; Degaetano, Arthur T.; Harrington, Laura C.

    2011-05-01

    Climate-based models simulating Culex mosquito population abundance in the Northeastern US were developed. Two West Nile vector species, Culex pipiens and Culex restuans, were included in model simulations. The model was optimized by a parameter-space search within biological bounds. Mosquito population dynamics were driven by major environmental factors including temperature, rainfall, evaporation rate and photoperiod. The results show a strong correlation between the timing of early population increases (as early warning of West Nile virus risk) and decreases in late summer. Simulated abundance was highly correlated with actual mosquito capture in New Jersey light traps and validated with field data. This climate-based model simulates the population dynamics of both the adult and immature mosquito life stage of Culex arbovirus vectors in the Northeastern US. It is expected to have direct and practical application for mosquito control and West Nile prevention programs.

  15. Climate-based models for West Nile Culex mosquito vectors in the Northeastern US.

    PubMed

    Gong, Hongfei; DeGaetano, Arthur T; Harrington, Laura C

    2011-05-01

    Climate-based models simulating Culex mosquito population abundance in the Northeastern US were developed. Two West Nile vector species, Culex pipiens and Culex restuans, were included in model simulations. The model was optimized by a parameter-space search within biological bounds. Mosquito population dynamics were driven by major environmental factors including temperature, rainfall, evaporation rate and photoperiod. The results show a strong correlation between the timing of early population increases (as early warning of West Nile virus risk) and decreases in late summer. Simulated abundance was highly correlated with actual mosquito capture in New Jersey light traps and validated with field data. This climate-based model simulates the population dynamics of both the adult and immature mosquito life stage of Culex arbovirus vectors in the Northeastern US. It is expected to have direct and practical application for mosquito control and West Nile prevention programs.

  16. Artificial Diets for Mosquitoes

    PubMed Central

    Gonzales, Kristina K.; Hansen, Immo A.

    2016-01-01

    Mosquito-borne diseases are responsible for more than a million human deaths every year. Modern mosquito control strategies such as sterile insect technique (SIT), release of insects carrying a dominant lethal (RIDL), population replacement strategies (PR), and Wolbachia-based strategies require the rearing of large numbers of mosquitoes in culture for continuous release over an extended period of time. Anautogenous mosquitoes require essential nutrients for egg production, which they obtain through the acquisition and digestion of a protein-rich blood meal. Therefore, mosquito mass production in laboratories and other facilities relies on vertebrate blood from live animal hosts. However, vertebrate blood is expensive to acquire and hard to store for longer times especially under field conditions. This review discusses older and recent studies that were aimed at the development of artificial diets for mosquitoes in order to replace vertebrate blood. PMID:28009851

  17. Fine-scale population genetic structure of a wildlife disease vector: The southern house mosquito on the island of Hawaii

    USGS Publications Warehouse

    Keyghobadi, N.; LaPointe, D.; Fleischer, R.C.; Fonseca, D.M.

    2006-01-01

    The southern house mosquito, Culex quinquefasciatus, is a widespread tropical and subtropical disease vector. In the Hawaiian Islands, where it was introduced accidentally almost two centuries ago, it is considered the primary vector of avian malaria and pox. Avian malaria in particular has contributed to the extinction and endangerment of Hawaii's native avifauna, and has altered the altitudinal distribution of native bird populations. We examined the population genetic structure of Cx. quinquefasciatus on the island of Hawaii at a smaller spatial scale than has previously been attempted, with particular emphasis on the effects of elevation on population genetic structure. We found significant genetic differentiation among populations and patterns of isolation by distance within the island. Elevation per se did not have a limiting effect on gene flow; however, there was significantly lower genetic diversity among populations at mid elevations compared to those at low elevations. A recent sample taken from just above the predicted upper altitudinal distribution of Cx. quinquefasciatus on the island of Hawaii was confirmed as being a temporary summer population and appeared to consist of individuals from more than one source population. Our results indicate effects of elevation gradients on genetic structure that are consistent with known effects of elevation on population dynamics of this disease vector. ?? 2006 The Authors.

  18. Mosquito Control

    MedlinePlus

    Jump to main content US EPA United States Environmental Protection Agency Search Search Share Facebook Twitter Google+ Pinterest Contact Us Mosquito Control About Mosquitoes General Information Life ...

  19. Population dynamics of pest mosquitoes and potential malaria and West Nile virus vectors in relation to climatic factors and human activities in the Camargue, France.

    PubMed

    Ponçon, N; Toty, C; L'ambert, G; le Goff, G; Brengues, C; Schaffner, F; Fontenille, D

    2007-12-01

    The Camargue is an extensive wetland in the southeast of France, which is highly influenced by human activities. Large ponds, marshes and irrigated fields provide abundant potential breeding sites for mosquitoes. mosquitoes, which are important in terms of the nuisance they cause to people and animals, the limitations they impose on tourism and their potential threat to human health. Several of the mosquito species present are potential vectors of malaria and West Nile virus. Therefore, the population dynamics of these species were monitored over an entire breeding season during March-October 2005. Mosquito populations were sampled in two study areas once every 2 weeks, using CDC light traps baited with CO(2). Sixteen species were collected. The majority (98.7%) of the catch were Aedes caspius (Pallas) (Diptera: Culicidae), Culex modestus (Ficalbi), Culex pipiens L. and Anopheles hyrcanus (Pallas). The population dynamics of these species varied considerably in relation to the species' biology, climatic conditions (rainfall, temperature and season), water management, implementation of mosquito control campaigns and landscape use.

  20. Wuchereria bancrofti infection in human and mosquito populations of a Polynesian village ten years after interruption of mass chemoprophylaxis with diethylcarbamazine.

    PubMed

    Cartel, J L; Nguyen, N L; Spiegel, A; Moulia-Pelat, J P; Plichart, R; Martin, P M; Manuellan, A B; Lardeux, F

    1992-01-01

    In 1991, a study on Wuchereria bancrofti microfilariae (mf) and infection rates was carried out in the human and mosquito populations of a Polynesian village where, 10 years before, the mf prevalence rate was 6.4% and twice-yearly mass treatment with 3 mg/kg of diethylcarbamazine (DEC) was interrupted. Venous blood samples were collected from 575 (97%) individuals aged 15 years or more, of whom 122 (21.4%) were mf positive. The mf carrier prevalence rate was 27.4% in males, significantly higher than that of 14% in females; it increased from 7-12% in the youngest age group (15-19 years) to 40-50% in the oldest (> or = 60 years) for both males and females. 387 mosquito collections were performed and 1748 female Aedes polynesiensis were dissected, of which 1176 were parous. Among the latter, 114 (9.7%) were infected with Wuchereria bancrofti larvae at L1, L2 or L3 stages. The mean number of larvae per mosquito was 2.46 (range 1-15). Of the 114 infected mosquitoes, 30 harboured L3 larvae, giving a 2.55% infective rate; the mean number of L3 larvae per mosquito was 1.15 (range 1-2). Such findings indicate that the interruption of systematic twice-yearly mass treatment with DEC (3 mg/kg) has resulted, after 10 years, in a substantial increase of microfilarial prevalence in humans, and in high infection rates in mosquitoes.

  1. Distribution and infection frequency of 'Candidatus Rickettsia amblyommii' in Maryland populations of the lone star tick (Amblyomma americanum) and culture in an Anopheles gambiae mosquito cell line.

    PubMed

    Zhang, Xing; Ren, Xiaoxia; Norris, Douglas E; Rasgon, Jason L

    2012-02-01

    Amblyomma americanum (the lone star tick) is a broadly distributed tick that transmits multiple pathogens of humans and domestic animals. 'Candidatus Rickettsia amblyommii' is a spotted-fever group rickettsial species that is potentially associated with human disease. In 2008 and 2009, we assayed over 500 unfed adult ticks from 19 Maryland populations for the presence of 'Candidatus R. amblyommii'. Infection frequencies ranged from 33% to 100%, with an average infection rate of 60% in 2008 and 69% in 2009. Infection frequencies did not differ statistically between sexes. To develop a system in which to study 'Candidatus R. amblyommii' in the laboratory, we used a cell line developed from Anopheles gambiae mosquitoes (Sua5B) to isolate and culture 'Candidatus R. amblyommii' from field-collected A. americanum ticks from 2 localities in Maryland. After infection, Sua5B cells were infected for more than 40 passages. Infection was confirmed by Rickettsia-specific PCR, gene sequencing, and Rickettsia-specific fluorescence in situ hybridization (FISH). These data show that 'Candidatus R. amblyommii' is widespread in Maryland A. americanum populations and that Sua5B cells are a useful tool for culturing Rickettsia infections from wild ticks.

  2. The Eye of the Tiger, the Thrill of the Fight: Effective Larval and Adult Control Measures Against the Asian Tiger Mosquito, Aedes albopictus (Diptera: Culicidae), in North America.

    PubMed

    Faraji, Ary; Unlu, Isik

    2016-09-01

    The Asian tiger mosquito, Aedes albopictus (Skuse), is a highly invasive container-inhabiting species with a global distribution. This mosquito, similar to other Stegomyia species such as Aedes aegypti (L.), is highly adapted to urban and suburban areas, and commonly oviposits in artificial containers, which are ubiquitous in these peridomestic environments. The increase in speed and amount of international travel and commerce, coupled with global climate change, have aided in the resurgence and expansion of Stegomyia species into new areas of North America. In many parts of their range, both species are implicated as significant vectors of emerging and re-emerging arboviruses such as dengue, chikungunya, and now Zika. Although rapid and major advances have been made in the field of biology, ecology, genetics, taxonomy, and virology, relatively little has changed in the field of mosquito control in recent decades. This is particularly discouraging in regards to container-inhabiting mosquitoes, because traditional integrated mosquito management (IMM) approaches have not been effective against these species. Many mosquito control programs simply do not possess the man-power or necessary financial resources needed to suppress Ae. albopictus effectively. Therefore, control of mosquito larvae, which is the foundation of IMM approaches, is exceptionally difficult over large areas. This review paper addresses larval habitats, use of geographic information systems for habitat preference detection, door-to-door control efforts, source reduction, direct application of larvicides, biological control agents, area-wide low-volume application of larvicides, hot spot treatments, autodissemination stations, public education, adult traps, attractive-toxic sugar bait methods, lethal ovitraps, barrier-residual adulticides, hand-held ultra-low-volume adulticides, area-wide adulticides applied by ground or air, and genetic control methods. The review concludes with future

  3. Population genetic structure of the dengue mosquito Aedes aegypti in Venezuela.

    PubMed

    Herrera, Flor; Urdaneta, Ludmel; Rivero, José; Zoghbi, Normig; Ruiz, Johanny; Carrasquel, Gabriela; Martínez, José Antonio; Pernalete, Martha; Villegas, Patricia; Montoya, Ana; Rubio-Palis, Yasmin; Rojas, Elina

    2006-09-01

    The mosquito Aedes aegypti is the main vector of dengue in Venezuela. The genetic structure of this vector was investigated in 24 samples collected from eight geographic regions separated by up to 1160 km. We examined the distribution of a 359-basepair region of the NADH dehydrogenase subunit 4 mitochondrial gene among 1144 Ae. aegypti from eight collections. This gene was amplified by the polymerase chain reaction and tested for variation using single strand conformation polymorphism analysis. Seven haplotypes were detected throughout Venezuela and these were sorted into two clades. Significant differentiation was detected among collections and these were genetically isolated by distance.

  4. Invasion of Wolbachia at the residential block level is associated with local abundance of Stegomyia aegypti, yellow fever mosquito, populations and property attributes.

    PubMed

    Hoffmann, A A; Goundar, A A; Long, S A; Johnson, P H; Ritchie, S A

    2014-08-01

    Wolbachia can suppress dengue and control mosquito populations and this depends on the successful invasion of Wolbachia-infected mosquitoes into local populations. Ovitrap data collected during the recent invasion of wMel-infected Stegomyia aegypti (Diptera: Culicidae) (Linnaeus) into Gordonvale near Cairns, Australia, were used to identify variables that help predict the success of localized invasion. Based on the variance in Wolbachia frequencies across Gordonvale as well as at another release site at Yorkeys Knob in comparison to simulations, it was estimated that on average 2-4 females contributed eggs to an ovitrap. By collating ovitrap data from two collection periods at the start of the release from residential blocks, it was found that uninfected mosquitoes had a patchy distribution across the release site. Residential blocks with relatively high uninfected mosquito numbers were less easily invaded by Wolbachia than blocks with low numbers. The numbers of uninfected mosquitoes in ovitraps were negatively correlated with the proportion of brick houses in a residential block, whereas local Wolbachia frequencies were correlated positively with this variable as well as negatively with the amount of shading in a yard and availability of breeding sites. These findings point to proxy measures for predicting the ease of localized invasion of Wolbachia.

  5. The heterodimeric glycoprotein hormone, GPA2/GPB5, regulates ion transport across the hindgut of the adult mosquito, Aedes aegypti.

    PubMed

    Paluzzi, Jean-Paul; Vanderveken, Mark; O'Donnell, Michael J

    2014-01-01

    A family of evolutionarily old hormones is the glycoprotein cysteine knot-forming heterodimers consisting of alpha- (GPA) and beta-subunits (GPB), which assemble by noncovalent bonds. In mammals, a common glycoprotein hormone alpha-subunit (GPA1) pairs with unique beta-subunits that establish receptor specificity, forming thyroid stimulating hormone (GPA1/TSHβ) and the gonadotropins luteinizing hormone (GPA1/LHβ), follicle stimulating hormone (GPA1/FSHβ), choriogonadotropin (GPA1/CGβ). A novel glycoprotein heterodimer was identified in vertebrates by genome analysis, called thyrostimulin, composed of two novel subunits, GPA2 and GPB5, and homologs occur in arthropods, nematodes and cnidarians, implying that this neurohormone system existed prior to the emergence of bilateral metazoans. In order to discern possible physiological roles of this hormonal signaling system in mosquitoes, we have isolated the glycoprotein hormone genes producing the alpha- and beta-subunits (AedaeGPA2 and AedaeGPB5) and assessed their temporal expression profiles in the yellow and dengue-fever vector, Aedes aegypti. We have also isolated a putative receptor for this novel mosquito hormone, AedaeLGR1, which contains features conserved with other glycoprotein leucine-rich repeating containing G protein-coupled receptors. AedaeLGR1 is expressed in tissues of the alimentary canal such as the midgut, Malpighian tubules and hindgut, suggesting that this novel mosquito glycoprotein hormone may regulate ionic and osmotic balance. Focusing on the hindgut in adult stage A. aegypti, where AedaeLGR1 was highly enriched, we utilized the Scanning Ion-selective Electrode Technique (SIET) to determine if AedaeGPA2/GPB5 modulated cation transport across this epithelial tissue. Our results suggest that AedaeGPA2/GPB5 does indeed participate in ionic and osmotic balance, since it appears to inhibit natriuresis and promote kaliuresis. Taken together, our findings imply this hormone may play an important

  6. Inter-population mating success in Australian dengue vector mosquitoes: effects of laboratory colonization and implications for the spread of transgenics.

    PubMed

    Richardson, Amanda J; Williams, Craig R

    2013-06-01

    Variability between Aedes aegypti populations in north Queensland, Australia, has the potential to impact the successful implementation of new population replacement mosquito releases for dengue control. Four Ae. aegypti colonies originating from different locations (Cairns, Mareeba, Innisfail, and Charters Towers), along with one F1 field-derived population from Cairns, were inter-crossed to determine any incompatibilities in copulation, insemination, and production of viable offspring. Greater copulation and insemination rates were observed when males recently introduced from the wild ('Cairns-Wild' population) were mated with long-term laboratory females. Egg viability rates for all crosses ranged from 90.2-98.2%, with no significant differences observed between crosses. Greater egg production was seen in some populations, and when corrected for wing-length, egg production was greatest in a Mareeba x Innisfail cross (19.55 eggs/mm wing length) and lowest for the Charters Towers intra-population cross (14.35 eggs/mm). Additionally, behavioral differences were observed between laboratory and wild mosquitoes from the Cairns location, suggesting possible laboratory conditioning. Finally, despite controlled larval rearing conditions, size differences between populations existed with Charters Towers mosquitoes consistently smaller than the other populations. The spread of genes or bacterial symbionts between these populations is unlikely to be hindered by pre-existing reproductive barriers.

  7. Resource Limitation, Controphic Ostracod Density and Larval Mosquito Development

    PubMed Central

    Rowbottom, Raylea; Carver, Scott; Barmuta, Leon A.; Weinstein, Philip; Foo, Dahlia; Allen, Geoff R.

    2015-01-01

    Aquatic environments can be restricted with the amount of available food resources especially with changes to both abiotic and biotic conditions. Mosquito larvae, in particular, are sensitive to changes in food resources. Resource limitation through inter-, and intra-specific competition among mosquitoes are known to affect both their development and survival. However, much less is understood about the effects of non-culicid controphic competitors (species that share the same trophic level). To address this knowledge gap, we investigated and compared mosquito larval development, survival and adult size in two experiments, one with different densities of non-culicid controphic conditions and the other with altered resource conditions. We used Aedes camptorhynchus, a salt marsh breeding mosquito and a prominent vector for Ross River virus in Australia. Aedes camptorhynchus usually has few competitors due to its halo-tolerance and distribution in salt marshes. However, sympatric ostracod micro-crustaceans often co-occur within these salt marshes and can be found in dense populations, with field evidence suggesting exploitative competition for resources. Our experiments demonstrate resource limiting conditions caused significant increases in mosquito developmental times, decreased adult survival and decreased adult size. Overall, non-culicid exploitation experiments showed little effect on larval development and survival, but similar effects on adult size. We suggest that the alterations of adult traits owing to non-culicid controphic competition has potential to extend to vector-borne disease transmission. PMID:26558896

  8. Mosquito surveillance for prevention and control of emerging mosquito-borne diseases in Portugal - 2008-2014.

    PubMed

    Osório, Hugo C; Zé-Zé, Líbia; Amaro, Fátima; Alves, Maria J

    2014-11-12

    Mosquito surveillance in Europe is essential for early detection of invasive species with public health importance and prevention and control of emerging pathogens. In Portugal, a vector surveillance national program-REVIVE (REde de VIgilância de VEctores)-has been operating since 2008 under the custody of Portuguese Ministry of Health. The REVIVE is responsible for the nationwide surveillance of hematophagous arthropods. Surveillance for West Nile virus (WNV) and other flaviviruses in adult mosquitoes is continuously performed. Adult mosquitoes-collected mainly with Centre for Disease Control light traps baited with CO2-and larvae were systematically collected from a wide range of habitats in 20 subregions (NUTS III). Around 500,000 mosquitoes were trapped in more than 3,000 trap nights and 3,500 positive larvae surveys, in which 24 species were recorded. The viral activity detected in mosquito populations in these years has been limited to insect specific flaviviruses (ISFs) non-pathogenic to humans. Rather than emergency response, REVIVE allows timely detection of changes in abundance and species diversity providing valuable knowledge to health authorities, which may take control measures of vector populations reducing its impact on public health. This work aims to present the REVIVE operation and to expose data regarding mosquito species composition and detected ISFs.

  9. More than one rabbit out of the hat: Radiation, transgenic and symbiont-based approaches for sustainable management of mosquito and tsetse fly populations.

    PubMed

    Bourtzis, Kostas; Lees, Rosemary Susan; Hendrichs, Jorge; Vreysen, Marc J B

    2016-05-01

    Mosquitoes (Diptera: Culicidae) and tsetse flies (Diptera: Glossinidae) are bloodsucking vectors of human and animal pathogens. Mosquito-borne diseases (malaria, filariasis, dengue, zika, and chikungunya) cause severe mortality and morbidity annually, and tsetse fly-borne diseases (African trypanosomes causing sleeping sickness in humans and nagana in livestock) cost Sub-Saharan Africa an estimated US$ 4750 million annually. Current reliance on insecticides for vector control is unsustainable: due to increasing insecticide resistance and growing concerns about health and environmental impacts of chemical control there is a growing need for novel, effective and safe biologically-based methods that are more sustainable. The integration of the sterile insect technique has proven successful to manage crop pests and disease vectors, particularly tsetse flies, and is likely to prove effective against mosquito vectors, particularly once sex-separation methods are improved. Transgenic and symbiont-based approaches are in development, and more advanced in (particularly Aedes) mosquitoes than in tsetse flies; however, issues around stability, sustainability and biosecurity have to be addressed, especially when considering population replacement approaches. Regulatory issues and those relating to intellectual property and economic cost of application must also be overcome. Standardised methods to assess insect quality are required to compare and predict efficacy of the different approaches. Different combinations of these three approaches could be integrated to maximise their benefits, and all have the potential to be used in tsetse and mosquito area-wide integrated pest management programmes.

  10. Molecular detection of Wolbachia pipientis in natural populations of mosquito vectors of Dirofilaria immitis from continental Portugal: first detection in Culex theileri.

    PubMed

    DE Pinho Mixão, V; Mendes, A M; Maurício, I L; Calado, M M; Novo, M T; Belo, S; Almeida, A P G

    2016-09-01

    Wolbachia pipientis (Rickettsiales: Rickettsiaceae) protects mosquitoes from infections with arboviruses and parasites. However, the effect of its co-infection on vector competence for Dirofilaria immitis (Spirurida: Onchocercidae) in the wild has not been investigated. This study aimed to screen vectors of D. immitis for wPip, to characterize these, and to investigate a possible association between the occurrence of W. pipientis and that of the nematode. The presence of W. pipientis was assessed in the five mosquito potential vectors of D. immitis in Portugal. Polymerase chain reaction (PCR) products were sequenced, and wPip haplotypes were determined by PCR-restricted fragment length polymorphism (RFLP). Results showed that wPip was detected in 61.5% of Culex pipiens (Diptera: Culicidae) pools and 6.3% of Culex theileri pools. wPip 16s rRNA sequences found in Cx. theileri exactly match those from Cx. pipiens, confirming a mosquito origin, rather than a nematode origin, as some specimens were infected with D. immitis. Only wPip haplotype I was found. No association was found between the presence of wPip and D. immitis in mosquitoes and hence a role for this endosymbiont in influencing vectorial competence is yet to be identified. This study contributes to understanding of wPip distribution in mosquito populations and, to the best of the authors' knowledge, is the first report of natural infections by wPip in Cx. theileri.

  11. Implications for operational control of adult mosquito production in cisterns and wells in St. Augustine, FL using attractive sugar baits.

    PubMed

    Qualls, Whitney A; Xue, Rudy; Revay, Edita E; Allan, Sandra A; Müller, Günter C

    2012-11-01

    The aim of this study was to further investigate the use of attractive sugar baits as an effective, inexpensive, and environmentally friendly tool for integrated mosquito management programs. Mosquitoes were offered dyed sugar bait in wells and cisterns in an urban tourist area in St. Augustine, FL. Exit traps were constructed to cover the well and cistern openings so the number of resting and emerging mosquitoes stained by feeding on the sugar bait could be monitored. Four mosquito species were collected from these structures: Aedes albopictus (Skuse), Anopheles crucians (Wiedemann), Culex quinquefasciatus Say, and Toxorhynchites rutilus rutilus (Coquillett). Overall, 90% (1482/1644) of the mosquitoes trapped were stained. In general, the number of mosquitoes stained was significantly greater in wells (P<0.0001) and cisterns (P<0.0001) than the numbers that were not stained by the colored bait. Based on the number of mosquitoes stained, we would have expected considerable mosquito mortality had the sugar bait contained an oral toxin. The results of this study support the concept of using attractive toxic sugar baits as an effective tool for integrated mosquito management.

  12. Insecticidal sugar baits for adult biting midges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the latest trends in mosquito control is the use of insecticidal sugar baits (ISBs) to reduce adult mosquito populations. Tested here is the ability of ISB’s to knock-down the biting midge, Culicoides sonorensis, a disease vector of bluetongue, epizootic hemorrhagic disease, and vesicular sto...

  13. Highly efficient Cas9-mediated gene drive for population modification of the malaria vector mosquito Anopheles stephensi.

    PubMed

    Gantz, Valentino M; Jasinskiene, Nijole; Tatarenkova, Olga; Fazekas, Aniko; Macias, Vanessa M; Bier, Ethan; James, Anthony A

    2015-12-08

    Genetic engineering technologies can be used both to create transgenic mosquitoes carrying antipathogen effector genes targeting human malaria parasites and to generate gene-drive systems capable of introgressing the genes throughout wild vector populations. We developed a highly effective autonomous Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated protein 9 (Cas9)-mediated gene-drive system in the Asian malaria vector Anopheles stephensi, adapted from the mutagenic chain reaction (MCR). This specific system results in progeny of males and females derived from transgenic males exhibiting a high frequency of germ-line gene conversion consistent with homology-directed repair (HDR). This system copies an ∼ 17-kb construct from its site of insertion to its homologous chromosome in a faithful, site-specific manner. Dual anti-Plasmodium falciparum effector genes, a marker gene, and the autonomous gene-drive components are introgressed into ∼ 99.5% of the progeny following outcrosses of transgenic lines to wild-type mosquitoes. The effector genes remain transcriptionally inducible upon blood feeding. In contrast to the efficient conversion in individuals expressing Cas9 only in the germ line, males and females derived from transgenic females, which are expected to have drive component molecules in the egg, produce progeny with a high frequency of mutations in the targeted genome sequence, resulting in near-Mendelian inheritance ratios of the transgene. Such mutant alleles result presumably from nonhomologous end-joining (NHEJ) events before the segregation of somatic and germ-line lineages early in development. These data support the design of this system to be active strictly within the germ line. Strains based on this technology could sustain control and elimination as part of the malaria eradication agenda.

  14. Implications for operational control of adult mosquito production in cisterns and wells in St. Augustine, Florida using attractive sugar baits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to further investigate the use of attractive sugar baits as an effective, inexpensive, and environmentally friendly tool for integrated mosquito management programs. Mosquitoes were offered dyed sugar bait in wells and cisterns in an urban tourist area in St. Augustine, Flo...

  15. Transmission Dynamics of the West Nile Virus in Mosquito Vector Populations under the Influence of Weather Factors in the Danube Delta, Romania.

    PubMed

    Cotar, Ani Ioana; Falcuta, Elena; Prioteasa, Liviu Florian; Dinu, Sorin; Ceianu, Cornelia Svetlana; Paz, Shlomit

    2016-12-01

    Mosquitoes were collected in the Danube Delta during the active seasons of 2011-2013. For Culex spp. mosquitoes, the abundance was calculated. Culex pipiens (sensu lato), (s.l.) and Culex modestus pools were tested for the presence of West Nile virus (WNV) genome, and the maximum likelihood of the infection rate was established. Mean daily temperatures and precipitation were obtained for the closest meteorological station. A negative binominal model was used to evaluate linkages between the temperature/precipitation and mosquito population size. A zero-inflated negative binomial model was used to test the relationship between the temperature and the infection rate. A single complex model for infection rate prediction was also used. The linkages were calculated for lag 0 and for 10 days earlier (lag 1), 20 days earlier (lag 2), and 30 days earlier (lag 3). Significant positive linkages (P < 0.001) were detected between temperature and mosquito population size for lag 1, lag 2, and lag 3. The linkages between temperature and infection rates were positive and significant for lag 2 and lag 3. Negative significant (P < 0.001) results were detected between precipitation and infection rates for lags 1, 2, and 3. The complex model showed that the best predictors for infection rate are the temperature, 20 days earlier (positive linkage) and the precipitation, 30 days earlier (negative linkage). Positive temperature anomalies in spring and summer and rainfall decrease contributed to the increase in the Culex spp. abundance and accelerated the WNV amplification in mosquito vector populations in the following weeks.

  16. Temporal Gene Expression Profiles of Pre Blood-Fed Adult Females Immediately Following Eclosion in the Southern House Mosquito Culex Quinquefasciatus

    PubMed Central

    Reid, William R.; Zhang, Lee; Liu, Nannan

    2015-01-01

    Prior to acquisition of the first host blood meal, the anautogenous mosquito Culex quinquefasciatus requires a period of time in order to prepare for the blood feeding and, later, vitellogenesis. In the current study, we conducted whole transcriptome analyses of adult female Culex mosquitoes to identify genes that may be necessary for both taking of the blood meal, and processing of the blood meal in adult female mosquitoes Cx. quinquefasciatus. We examined temporal expression of genes for the periods of post eclosion and prior to the female freely taking a blood meal. We further evaluated the temporal expression of certain genes for the periods after the taking of a blood meal to identify genes that may be necessary for both the taking of the blood meal, and the processing of the blood meal. We found that adult females required a minimum of 48 h post-eclosion before they freely took their first blood meal. We hypothesized that gene expression signatures were altered in the mosquitoes before blood feeding in preparation for the acquisition of the blood meal through changes in multiple gene expression. To identify the genes involved in the acquisition of blood feeding, we quantified the gene expression levels of adult female Cx. quinquefasciatus using RNA Seq throughout a pre-blooding period from 2 to 72 h post eclosion at 12 h intervals. A total of 325 genes were determined to be differentially-expressed throughout the pre-blooding period, with the majority of differentially-expressed genes occurring between the 2 h and 12 h post-eclosion time points. Among the up-regulated genes were salivary proteins, cytochrome P450s, odorant-binding proteins, and proteases, while the majority of the down-regulated genes were hypothetical or cuticular genes. In addition, Trypsin was found to be up-regulated immediately following blood feeding, while trypsin and chymotrypsin were up-regulated at 48h and 60h post blood-feeding, respectively, suggesting that these proteases are

  17. Genetic Control Of Malaria Mosquitoes.

    PubMed

    McLean, Kyle Jarrod; Jacobs-Lorena, Marcelo

    2016-03-01

    Experiments demonstrating the feasibility of genetically modifying mosquito vectors to impair their ability to transmit the malaria parasite have been known for well over a decade. However, means to spread resistance or population control genes into wild mosquito populations remains an unsolved challenge. Two recent reports give hope that CRISPR technology may allow such challenge to be overcome.

  18. Genetic Control Of Malaria Mosquitoes

    PubMed Central

    McLean, Kyle Jarrod; Jacobs-Lorena, Marcelo

    2016-01-01

    Experiments demonstrating the feasibility of genetically modifying mosquito vectors to impair their ability to transmit the malaria parasite have been known for well over a decade. However, means to spread resistance or population control genes into wild mosquito populations remains an unsolved challenge. Two recent reports give hope that CRISPR technology may allow such challenge to be overcome. PMID:26809567

  19. Effect of Quorum Sensing by Staphylococcus epidermidis on the Attraction Response of Female Adult Yellow Fever Mosquitoes, Aedes aegypti aegypti (Linnaeus) (Diptera: Culicidae), to a Blood-Feeding Source

    PubMed Central

    Zhang, Xinyang; Crippen, Tawni L.; Coates, Craig J.; Wood, Thomas K.; Tomberlin, Jeffery K.

    2015-01-01

    Aedes aegypti, the principal vector of yellow fever and dengue fever, is responsible for more than 30,000 deaths annually. Compounds such as carbon dioxide, amino acids, fatty acids and other volatile organic compounds (VOCs) have been widely studied for their role in attracting Ae. aegypti to hosts. Many VOCs from humans are produced by associated skin microbiota. Staphyloccocus epidermidis, although not the most abundant bacteria according to surveys of relative 16S ribosomal RNA abundance, commonly occurs on human skin. Bacteria demonstrate population level decision-making through quorum sensing. Many quorum sensing molecules, such as indole, volatilize and become part of the host odor plum. To date, no one has directly demonstrated the link between quorum sensing (i.e., decision-making) by bacteria associated with a host as a factor regulating arthropod vector attraction. This study examined this specific question with regards to S. epidermidis and Ae. aegypti. Pairwise tests were conducted to examine the response of female Ae. aegypti to combinations of tryptic soy broth (TSB) and S. epidermidis wildtype and agr- strains. The agr gene expresses an accessory gene regulator for quorum sensing; therefore, removing this gene inhibits quorum sensing of the bacteria. Differential attractiveness of mosquitoes to the wildtype and agr- strains was observed. Both wildtype and the agr- strain of S. epidermidis with TSB were marginally more attractive to Ae. aegypti than the TSB alone. Most interestingly, the blood-feeder treated with wildtype S. epidermidis/TSB attracted 74% of Ae. aegypti compared to the agr- strain of S. epidermidis/TSB (P ≤ 0.0001). This study is the first to suggest a role for interkingdom communication between host symbiotic bacteria and mosquitoes. This may have implications for mosquito decision-making with regards to host detection, location and acceptance. We speculate that mosquitoes “eavesdrop” on the chemical discussions occurring

  20. Effect of Quorum Sensing by Staphylococcus epidermidis on the Attraction Response of Female Adult Yellow Fever Mosquitoes, Aedes aegypti aegypti (Linnaeus) (Diptera: Culicidae), to a Blood-Feeding Source.

    PubMed

    Zhang, Xinyang; Crippen, Tawni L; Coates, Craig J; Wood, Thomas K; Tomberlin, Jeffery K

    2015-01-01

    Aedes aegypti, the principal vector of yellow fever and dengue fever, is responsible for more than 30,000 deaths annually. Compounds such as carbon dioxide, amino acids, fatty acids and other volatile organic compounds (VOCs) have been widely studied for their role in attracting Ae. aegypti to hosts. Many VOCs from humans are produced by associated skin microbiota. Staphyloccocus epidermidis, although not the most abundant bacteria according to surveys of relative 16S ribosomal RNA abundance, commonly occurs on human skin. Bacteria demonstrate population level decision-making through quorum sensing. Many quorum sensing molecules, such as indole, volatilize and become part of the host odor plum. To date, no one has directly demonstrated the link between quorum sensing (i.e., decision-making) by bacteria associated with a host as a factor regulating arthropod vector attraction. This study examined this specific question with regards to S. epidermidis and Ae. aegypti. Pairwise tests were conducted to examine the response of female Ae. aegypti to combinations of tryptic soy broth (TSB) and S. epidermidis wildtype and agr- strains. The agr gene expresses an accessory gene regulator for quorum sensing; therefore, removing this gene inhibits quorum sensing of the bacteria. Differential attractiveness of mosquitoes to the wildtype and agr- strains was observed. Both wildtype and the agr- strain of S. epidermidis with TSB were marginally more attractive to Ae. aegypti than the TSB alone. Most interestingly, the blood-feeder treated with wildtype S. epidermidis/TSB attracted 74% of Ae. aegypti compared to the agr- strain of S. epidermidis/TSB (P ≤ 0.0001). This study is the first to suggest a role for interkingdom communication between host symbiotic bacteria and mosquitoes. This may have implications for mosquito decision-making with regards to host detection, location and acceptance. We speculate that mosquitoes "eavesdrop" on the chemical discussions occurring between

  1. Anopheles arabiensis egg treatment with dieldrin for sex separation leaves residues in male adult mosquitoes that can bioaccumulate in goldfish (Carassius auratus auratus)

    PubMed Central

    Yamada, Hanano; Jandric, Zora; Chhem-Kieth, Sorivan; Vreysen, Marc JB; Rathor, Mohammad N; Gilles, Jeremie RL; Cannavan, Andrew

    2013-01-01

    The sterile insect technique (SIT) is a biological control tactic that is used as a component of area-wide integrated pest management (AW-IPM) programs. The SIT can only be applied against disease-transmitting mosquitoes when only sterile male mosquitoes are released, and the blood-sucking and potentially disease-transmitting females are eliminated from the production line. For Anopheles arabiensis, a potent vector of malaria, a genetic sexing strain was developed whereby females can be eliminated by treating the eggs or larvae with the insecticide dieldrin. To evaluate the presence of dieldrin residues in male mosquitoes designated for SIT releases, a simple, sensitive, and accurate gas chromatography–electron capture detector (GC–ECD) method was developed. In addition, bioaccumulation and food chain transfer of these residues to fish after feeding with treated mosquitoes was demonstrated. The overall recovery from method validation studies was 77.3 ± 2.2% (mean ± relative standard deviation [RSD]) for the mosquitoes, and 99.1 ± 4.4% (mean ± RSD) for the fish. The average dieldrin concentration found in adult male An. arabiensis was 28.1 ± 2.9 µg/kg (mean ± standard deviation [SD]). A range of 23.9 ± 1.1 µg/kg to 73.9 ± 5.2 µg/kg (mean ± SD) of dieldrin was found in the fish samples. These findings indicate the need to reassess the environmental and health implications of control operations with a SIT component against An. arabiensis that involves using persistent organochlorines in the sexing process. PMID:23983078

  2. Repellency of essential oils of Cryptomeria japonica (Pinaceae) against adults of the mosquitoes Aedes aegypti and Aedes albopictus (Diptera:Culicidae).

    PubMed

    Gu, Hui-Jing; Cheng, Sen-Sung; Lin, Chun-Ya; Huang, Chin-Gi; Chen, Wei-June; Chang, Shang-Tzen

    2009-12-09

    The purpose of this study was to investigate the repellent activities of essential oils from Cryptomeria japonica (sugi) against adults of mosquitoes Aedes aegypti and Aedes albopictus . Comparison of essential oils from four different plant parts of C. japonica revealed that essential oil from its leaf exhibited the best repellent activity against mosquitoes. To understand the relationship between volatile organic compounds and repellent activity, the solid-phase microextraction (SPME) method was employed to analyze volatile organic compounds of leaf essential oil. The SPME fiber was coated with divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS). The major volatile organic compounds in the cage were 3-carene, alpha-terpinene, limonene, gamma-terpinene, and terpinolene at 0 min. Results demonstrated that (-)-terpinen-4-ol was the major volatile organic compound adsorbed by SPME fiber during repellent assays. Furthermore, the repellent activities of six compounds against adults of the mosquitoes were evaluated, and the results revealed that (-)-terpinen-4-ol exhibited the best repellent activity against A. aegypti and A. albopictus.

  3. Associations between two mosquito populations and West Nile virus in Harris County, Texas, 2003-06.

    PubMed

    Dennett, James A; Bala, Adilelkhidir; Wuithiranyagool, Taweesak; Randle, Yvonne; Sargent, Christopher B; Guzman, Hilda; Siirin, Marina; Hassan, Hassan K; Reyna-Nava, Martin; Unnasch, Thomas R; Tesh, Robert B; Parsons, Ray E; Bueno, Rudy

    2007-09-01

    Associations between Culex quinquefasciatus, Aedes albopictus and West Nile virus (WNV) activity, temperature, and rainfall in Harris County, Texas 2003-06 are discussed. Human cases were highly correlated to Cx. quinquefasciatus (r = 0.87) and Ae. albopictus (r = 0.78) pools, blue jays (r = 0.83), and Ae. albopictus collected (r = 0.71), but not Cx. quinquefasciatus collected (r = 0.45). Human cases were associated with temperature (r = 0.71), not rainfall (r = 0.29), whereas temperature correlated with Ae. albopictus and Cx. quinquefasciatus collections (r = 0.88 and 0.70, respectively) and Cx. quinqueftsciatus pools (r = 0.75), but not Ae. albopictus pools (r = 0.55). Both species (collections and pools) and blue jays were weakly correlated (r 5 0.41) with rainfall, but blue jays were better correlated with Cx. quinquefasciatus pools (r = 0.87), compared with Ae. albopictus pools (r = 0.67), Ae. albopictus collections (r = 0.69), and Cx. quinquefasciatus collections (r = 0.46). Peak minimum infection rate for Cx. quinquefasciatus (4.55), and Ae. albopictus (4.41) was in August with highest human cases (17.87), blue jays (55.58), and temperature (29.01 degrees C). Between both species, blood meal analysis indicated 68.18% of Cx. quinquefasciatus mammalian hosts were dog, while 22.72% were human, whereas Ae. albopictus had higher human (44.44%) but fewer dog hosts (22.22%). Ten bird species were identified as hosts for Cx. quinquefasciatus, with northern cardinal and blue jay representing 26.66% and 20.00%, respectively. No bird feeding activity was observed in Ae. albopictus. The earliest and latest human blood meal occurred in May (Ae. albopictus) and November (Cx. quinquefasciatus); 66.66% of human host identifications between both species occurred in October-November, after the seasonal human case peak. Based upon our data, WNV activity in both mosquito species warrants further investigation of their individual roles in WNV ecology within this region.

  4. Role of modified CDC miniature light-traps as an alternative method for sampling adult anophelines (Diptera: Culicidae) in the National Mosquito Surveillance Programme in India.

    PubMed

    Sadanandane, C; Jambulingam, P; Subramanian, S

    2004-02-01

    The efficiency of modified CDC miniature light-traps for sampling adult mosquitoes was evaluated in comparison with indoor resting, outdoor resting, indoor man-landing and outdoor man-landing collections in the hilly district of Koraput, Orissa, India. Overall, light-traps captured 78% of adult mosquitoes collected by all methods. Of the 16 anopheline species recorded in the study area, light-traps effectively sampled 13, contributing about 72% of the total anophelines collected by all methods. Light-traps also caught a large number of female Culex vishnui Theobald (96%). As fully-fed mosquitoes were predominant (82%) and caught alive, light-traps can be used to catch large numbers of vector mosquitoes for studies on vector prevalence, distribution, vector incrimination and also for laboratory bioassays. Light-trap and indoor resting collections revealed similar seasonal trends in numbers of Anopheles culicifacies Giles, A. fluviatilis James, A. jeyporiensis James, A. vagus Doenitz, and A. splendidus Koidzumi. Age-structure of the samples did not vary significantly between the two methods. Light-traps could be used as an alternative to daytime indoor resting collections to monitor the seasonal fluctuations in the abundance and parity rates of these species. The light-trap collections correlated with indoor and outdoor man-landing collections of A. jeyporiensis and the outdoor man-landing collections of A. maculatusTheobald in measuring seasonal trends. Light-trap collections can thus be used as a substitute for man-landing collections of A. jeyporiensis and A. maculatus.

  5. Efficacy of three attractant blends tested in combination with carbon dioxide against natural populations of mosquitoes and biting flies at the Lower Suwannee Wildlife Refuge.

    PubMed

    Kline, Daniel L; Bernier, Ulrich R; Hogsette, Jerome A

    2012-06-01

    Synthetic blends of chemicals identified previously from human skin emanations were evaluated against mosquito and biting fly populations at the Lower Suwannee Wildlife Refuge near Cedar Key, FL. Mosquito Magnet-Experimental traps were baited with the Red (400 ml acetone: 10 ml 1-hexen-3-ol:10 ml 1-octen-3-ol), Blue (400 ml acetone: 1 g/liter lactic acid:20 ml glycolic acid), or Green blend (400 ml acetone:1.5 g/liter lactic acid:20 ml dimethyl disulfide) plus CO2 or with CO2 alone (control). A relative index of efficacy was determined by dividing each mean blend trap catch by the mean control trap catch. Five mosquitoes (Aedes infirmatus, Ae. taeniorhynchus, Ae. triseriatus, Anopheles crucians, and Culex nigripalpus), 2 ceratopogonid (Culicoides floridensis and C. furens), and 1 tabanid (Diachlorus ferrugatus) and phlebotomine (Lutzomyia shannoni) species were trapped. The Red blend + CO2 treatment significantly increased collections of Ae. taeniorhynchus (3.4x), An. crucians (2.8X), total mosquitoes (2.7x), C. furens (17.6x), and L. shannoni (10.8x) compared with control traps. Traps baited with either the Blue or Green blends generally captured fewer insects than traps baited with the other 2 treatments. However, traps baited with the Green blend caught 7 x as many C. furens as the control traps. Responses clearly varied according to species; therefore, "one size does not fit all" when it comes to attractant blends.

  6. West Nile Virus in Mosquitoes of Iranian Wetlands.

    PubMed

    Bagheri, Masoomeh; Terenius, Olle; Oshaghi, Mohammad Ali; Motazakker, Morteza; Asgari, Sassan; Dabiri, Farrokh; Vatandoost, Hassan; Mohammadi Bavani, Mulood; Chavshin, Ali Reza

    2015-12-01

    The West Nile virus (WNV) transmission cycle includes a wide range of migratory wetland birds as reservoirs, mosquitoes as biological vectors, and equines and humans as dead-end hosts. Despite the presence of potential vector species, there is no information about the existence of WNV in mosquito vectors in Iran. The Iranian West Azerbaijan Province is located in the northwestern part of Iran and has borders with Turkey, Iraq, Armenia, and the Republic of Azerbaijan. The current study was conducted to identify the wetland mosquitoes of the West Azerbaijan Province and their infection with WNV. In this study, 2143 specimens were collected, comprising 1541 adults and 602 larvae. Six species belonging to four genera were collected and identified: Anopheles maculipennis sensu lato (s.l.), Culex (Cx.) hortensis, Cx. pipiens s.l., Cx. theileri, Culiseta longiareolata, and Aedes (Ae.) (Ochlerotatus) caspius. In total, 45 pools of mosquitoes were examined. Two of the adult pools collected from the same location showed the presence of WNV in Ae. (Och.) caspius, from Sangar, Makoo County, as confirmed by PCR and sequencing. Due to the discovery of WNV in the mosquito population of the region, and the presence of wetlands and significant populations of migratory birds, the health sector should carefully monitor the factors involved in the cycle of this disease.

  7. Effects of Biogents Sentinel Trap Field Placement on Capture Rates of Adult Asian Tiger Mosquitoes, Aedes albopictus

    PubMed Central

    Crepeau, Taryn N.; Healy, Sean P.; Bartlett-Healy, Kristen; Unlu, Isik; Farajollahi, Ary; Fonseca, Dina M.

    2013-01-01

    The Biogents® Sentinel (BGS) trap is the standard tool to monitor adult Aedes (Stegomyia) albopictus (Skuse) (Diptera: Culicidae), the Asian tiger mosquito. BGS traps are commonly placed in residential properties during surveillance operations, but locations within properties may have significant differences in ambient light, temperature, and humidity (e.g. between a sunlit lawn and shady underbrush). We examined the effect of BGS trap placement on Ae. albopictus capture rates in three residential properties in Monmouth County, New Jersey, USA. In each property we visually selected locations as shade, partial shade, and sun. Traps in “partial shade” locations were under vegetation and were exposed to filtered sunlight during some parts of the day while “shaded” locations were never exposed to direct sunlight. Locations defined as “sun” were exposed to direct sunlight for large parts of the day. We placed a BGS trap in each of the three location types and used small data loggers to measure temperature, relative humidity, and light exposure at each trap during a 24-hour deployment. To address temporal variability, we made seven separate measurements from 31 August to 22 September 2010. We found that “partial shade” and “full shade” locations did not differ but that “full sun” locations had significantly higher light exposure, higher temperature, and lower humidity. Importantly, Ae. albopictus catches (males, females, or both) were consistently and significantly over 3 times higher in traps located in shaded locations. To further investigate the effects of local temperature and humidity on surveillance we examined Ae. albopictus collections from 37 BGS traps fitted with data loggers and deployed weekly from August through mid October, during the 2009 season, in three urban sites in Mercer County, NJ. We confirmed that local climate influences capture rates and that Ae. albopictus surveillance projects need to monitor trap placement carefully

  8. Delayed action insecticides and their role in mosquito and malaria control.

    PubMed

    Wang, Chuncheng; Gourley, Stephen A; Liu, Rongsong

    2014-01-01

    There is considerable interest in the management of insecticide resistance in mosquitoes. One possible approach to slowing down the evolution of resistance is to use late-life-acting (LLA) insecticides that selectively kill only the old mosquitoes that transmit malaria, thereby reducing selection pressure favoring resistance. In this paper we consider an age-structured compartmental model for malaria with two mosquito strains that differ in resistance to insecticide, using an SEI approach to model malaria in the mosquitoes and thereby incorporating the parasite developmental times for the two strains. The human population is modeled using an SEI approach. We consider both conventional insecticides that target all adult mosquitoes, and LLA insecticides that target only old mosquitoes. According to linearised theory the potency of the insecticide affects mainly the speed of evolution of resistance. Mutations that confer resistance can also affect other parameters such as mean adult life span and parasite developmental time. For both conventional and LLA insecticides the stability of the malaria-free equilibrium, with only the resistant mosquito strain present, depends mainly on these other parameters. This suggests that the main long term role of an insecticide could be to induce genetic changes that have a desirable effect on a vital parameter such as adult life span. However, when this equilibrium is unstable, numerical simulations suggest that a potent LLA insecticide can slow down the spread of malaria in humans but that the timing of its action is very important.

  9. A lethal ovitrap-based mass trapping scheme for dengue control in Australia: II. Impact on populations of the mosquito Aedes aegypti.

    PubMed

    Rapley, L P; Johnson, P H; Williams, C R; Silcock, R M; Larkman, M; Long, S A; Russell, R C; Ritchie, S A

    2009-12-01

    In Cairns, Australia, the impacts on Aedes aegypti L. (Diptera: Culicidae) populations of two types of 'lure & kill' (L&K) lethal ovitraps (LOs), the standard lethal ovitrap (SLO) and the biodegradable lethal ovitrap (BLO) were measured during three mass-trapping interventions. To assess the efficacy of the SLO, two interventions (one dry season and one wet season) were conducted in three discrete areas, each lasting 4 weeks, with the following treatments: (i) SLOs (>200 traps, approximately 4/premise), BG-sentinel traps (BGSs; approximately 15, 1/premise) and larval control (container reduction and methoprene treatment) and (ii) larval control alone, and (iii) untreated control. Female Ae. aegypti populations were monitored for 4 weeks pre- and post-treatment in all three areas using BGSs and sticky ovitraps (SOs) or non-lethal regular ovitraps (ROs). In the dry season, 206 SLOs and 15 BGSs set at 54 and 15 houses, respectively, caught and killed an estimated 419 and 73 female Ae. aegypti, respectively. No significant decrease in collection size of female Ae. aegypti could be attributed to the treatments. In the wet season, 243 SLOs and 15 BGSs killed approximately 993 and 119 female Ae. aegypti, respectively. The mean number of female Ae. aegypti collected after 4 weeks with SOs and BGSs was significantly less than the control (LSD post-hoc test). The third mass-trapping intervention was conducted using the BLO during the wet season in Cairns. For this trial, three treatment areas were each provided with BLOs (>500, approximately 4/premise) plus larval control, and an untreated control area was designated. Adult female Ae. aegypti were collected for 4 weeks pre- and post-treatment using 15 BGSs and 20 SOs. During this period, 53.2% of BLOs contained a total of 6654 Ae. aegypti eggs. Over the intervention period, collections of Ae. aegypti in the treatment areas were significantly less than in the control area for BGSs but not SOs. An influx of relatively large

  10. Mosquito Surveillance for Prevention and Control of Emerging Mosquito-Borne Diseases in Portugal — 2008–2014

    PubMed Central

    Osório, Hugo C.; Zé-Zé, Líbia; Amaro, Fátima; Alves, Maria J.

    2014-01-01

    Mosquito surveillance in Europe is essential for early detection of invasive species with public health importance and prevention and control of emerging pathogens. In Portugal, a vector surveillance national program—REVIVE (REde de VIgilância de VEctores)—has been operating since 2008 under the custody of Portuguese Ministry of Health. The REVIVE is responsible for the nationwide surveillance of hematophagous arthropods. Surveillance for West Nile virus (WNV) and other flaviviruses in adult mosquitoes is continuously performed. Adult mosquitoes—collected mainly with Centre for Disease Control light traps baited with CO2—and larvae were systematically collected from a wide range of habitats in 20 subregions (NUTS III). Around 500,000 mosquitoes were trapped in more than 3,000 trap nights and 3,500 positive larvae surveys, in which 24 species were recorded. The viral activity detected in mosquito populations in these years has been limited to insect specific flaviviruses (ISFs) non-pathogenic to humans. Rather than emergency response, REVIVE allows timely detection of changes in abundance and species diversity providing valuable knowledge to health authorities, which may take control measures of vector populations reducing its impact on public health. This work aims to present the REVIVE operation and to expose data regarding mosquito species composition and detected ISFs. PMID:25396768

  11. Changes in distribution and abundance of mosquito populations in an ecological research tract over a 35-year period.

    PubMed

    Butts, William L

    2004-09-01

    Marked changes in species and numbers of mosquitoes have occurred over a 35-year period. Changes relate to alteration of available larval development sites by beaver (Castor canadensis), variation in winter and spring precipitation, and differences in feeding behaviors.

  12. Determinants of the population growth of the West Nile virus mosquito vector Culex pipiens in a repeatedly affected area in Italy

    PubMed Central

    2014-01-01

    Background The recent spread of West Nile Virus in temperate countries has raised concern. Predicting the likelihood of transmission is crucial to ascertain the threat to Public and Veterinary Health. However, accurate models of West Nile Virus (WNV) expansion in Europe may be hampered by limited understanding of the population dynamics of their primary mosquito vectors and their response to environmental changes. Methods We used data collected in north-eastern Italy (2009–2011) to analyze the determinants of the population growth rate of the primary WNV vector Culex pipiens. A series of alternative growth models were fitted to longitudinal data on mosquito abundance to evaluate the strength of evidence for regulation by intrinsic density-dependent and/or extrinsic environmental factors. Model-averaging algorithms were then used to estimate the relative importance of intrinsic and extrinsic variables in describing the variations of per-capita growth rates. Results Results indicate a much greater contribution of density-dependence in regulating vector population growth rates than of any environmental factor on its own. Analysis of an average model of Cx. pipiens growth revealed that the most significant predictors of their population dynamics was the length of daylight, estimated population size and temperature conditions in the 15 day period prior to sampling. Other extrinsic variables (including measures of precipitation, number of rainy days, and humidity) had only a minor influence on Cx. pipiens growth rates. Conclusions These results indicate the need to incorporate density dependence in combination with key environmental factors for robust prediction of Cx. pipiens population expansion and WNV transmission risk. We hypothesize that detailed analysis of the determinants of mosquito vector growth rate as conducted here can help identify when and where an increase in vector population size and associated WNV transmission risk should be expected. PMID:24428887

  13. Field Comparison of Cyclopentanone Versus Carbon Dioxide as an Attractant for Adult Mosquitoes in Southeast Queensland, Australia.

    PubMed

    Philippe-Janon, J C D; van den Hurk, A F; Francis, D P; Shivas, M A; Jansen, C C

    2015-05-01

    Cyclopentanone is a saturated monoketone typically used as an intermediate in the manufacture of pharmaceuticals, biologicals, insecticides, and rubber chemicals. Recently, it has been demonstrated that cyclopentanone activates the cpA CO2 receptor neuron on the maxillary palp of mosquitoes, suggesting that it may be a viable alternative to CO2 as an attractant for mosquitoes. Furthermore, semifield experiments showed that traps baited with cyclopentanone attract Culex quinquefasciatus Say at a similar rate to those baited with CO2. We evaluated the field efficacy of cyclopentanone as an alternative to CO2 in Centers for Disease Control (CDC) light traps and counterflow geometry (CFG) traps commonly used to collect mosquitoes in surveillance programs. Three pairwise trials and four Latin square trials were conducted across three peri-urban sites, comprising two saltwater sites and one freshwater site, in southeast Queensland, Australia. In all trials, CO2-baited traps outperformed traps baited with cyclopentanone. Carbon dioxide-baited CDC traps collected significantly more total mosquitoes, Aedes vigilax (Skuse), Culex sitiens Weidemann, and Culex annulirostris Skuse, than those baited with ≥99% cyclopentanone in pairwise trials. Similarly, in almost all Latin square trials, CO2-baited CDC and CFG traps collected significantly greater numbers of total mosquitoes, Ae. vigilax, Cx. annulirostris, Culex orbostiensis Dobrotworsky, and Cx. sitiens when compared with CFG traps baited with 20% cyclopentanone. Our trials indicate that cyclopentanone is not effective as a mosquito attractant in the field and cannot be used as a simple substitute for CO2 in commonly used mosquito surveillance traps.

  14. Changes in local mosquito fauna following beaver (Castor canadensis) activity--an update.

    PubMed

    Butts, W L

    1992-09-01

    Drastic reduction of populations of univoltine temporary pool mosquitoes followed impoundment of breeding areas by beavers. Mosquito populations persist at very low levels over a 10-year period with no evidence of mosquito development in the impoundment.

  15. Morphological studies on adult mosquitoes (Diptera: Culicidae) and first report of the potential Zika virus vector Aedes (Stegomyia) unilineatus (Theobald, 1906) in Iran.

    PubMed

    Yaghoobi-Ershadi, M R; Doosti, S; Schaffner, F; Moosa-Kazemi, S H; Akbarzadeh, K; Yaghoobi-Ershadi, N

    2016-12-27

    Beside numerous extensive studies on Anophelinae mosquitoes of Iran, little is known on Aedes species in the country and existing reports are dispersed. The objective of this study was to identify adults of Culicinae species occurring in the Sistan and Baluchestan Province, southeast of Iran, during 2012-2014. Mosquito collections were carried out three times (May-June, September, October-November) in four counties by Centers for Diseases Control (CDC) light traps and human landing catches outdoors and under bed nets baited with carbon dioxide. These trapping were carried out two consecutive nights during the field studies. Several mosquito collections were also conducted with aspirator and pyrethrum spray space catches during the day. A total of 1885 mosquitoes were collected, belonging to 10 species of genus Culex including Cx. pipiens Complex, Cx. laticinctus, Cx. sinaiticus, and Cx. tritaeniorhynchus, one species of the genus Culiseta, Cs. longiareolata, and five species of the genus Aedes, Ae. caspius, Ae. vexans, Ae. detritus, Ae. albopictus, and Ae. unilineatus. Ae. vexans was the dominant species in the area (77.7%). During the study, seven Ae. unilineatus were collected in two villages near the city of Chabahar located in a coastal area; this is the first record for Iran and identification was confirmed by Cytochrome oxidase (COI) sequences analysis. Confirmation of the presence of Ae. unilineatus in the country raises the number of species of the genus Aedes to 12. The detection of this species reveals its probable establishment in the southeast of the country, which has implications for public health such as dengue and Zika infections and requires active entomological surveillance and implementation of adapted vector control measures in the area.

  16. Effects of Organic Amendments on Microbiota Associated with the Culex nigripalpus Mosquito Vector of the Saint Louis Encephalitis and West Nile Viruses

    PubMed Central

    Hall, Michael W.; Smartt, Chelsea T.

    2017-01-01

    ABSTRACT Pollution from nutrients in aquatic habitats has been linked to increases in disease vectors, including mosquitoes and other pestiferous insects. One possibility is that changes in mosquito microbiomes are impacted by nutrient enrichments and that these changes affect various traits, including larval development, susceptibility to larval control agents, and susceptibility of the adult mosquitoes to pathogens. We tested this hypothesis using field mesocosms supplemented with low- and high-organic-nutrient regimens and then sampled microbial communities associated with the naturally colonizing Culex nigripalpus mosquito vector. By high-throughput sequencing of 16S rRNA gene sequences, we found no significant differences in overall microbial communities associated with sampled mosquitoes, despite detecting discernible differences in environmental variables, including pH, dissolved oxygen, and nutrient amendments. Nevertheless, indicator species analysis revealed that members of the Clostridiales were significantly associated with mosquitoes that originated from high-nutrient enrichments. In contrast, members of the Burkholderiales were associated with mosquitoes from the low-nutrient enrichment. High bacterial variability associated with the life stages of the C. nigripalpus was largely unaffected by levels of nutrient enrichments that impacted larval microbial resources, including bacteria, ciliates, and flagellates in the larval environments. IMPORTANCE Mosquito microbiota provide important physiological and ecological attributes to mosquitoes, including an impact on their susceptibility to pathogens, fitness, and sensitivity to mosquito control agents. Culex nigripalpus mosquito populations transmit various pathogens, including the Saint Louis and West Nile viruses, and proliferate in nutrient-rich environments, such as in wastewater treatment wetlands. Our study examined whether increases in nutrients within larval mosquito developmental habitats impact

  17. Biological control of mosquitoes in scrap tires in Brownsville, Texas, USA and Matamoros, Tamaulipas, Mexico.

    PubMed

    Uejio, Christopher K; Hayden, Mary H; Zielinski-Gutierrez, Emily; Lopez, Jose Luis Robles; Barrera, Roberto; Amador, Manuel; Thompson, Gregory; Waterman, Stephen H

    2014-06-01

    Dengue periodically circulates in southern Texas and neighboring Tamaulipas, Mexico; thus, a closer examination of human and vector ecology at the northern limits of North American transmission may improve prevention activities. Scrap tires produce large mosquito populations and increase the risk of dengue transmission. Some households choose not to pay tire disposal fees, and many tires are illegally dumped in residential areas. Biological control may provide low-cost and environmentally friendly mosquito control. This pilot study evaluated the ability of Mesocyclops longisetus to reduce mosquito populations in existing residential scrap tire piles. Mosquito populations were measured by the number of all mosquito pupae within tires or adult Aedes aegypti and Ae. albopictus near piles. Mesocyclops longisetus treated piles did not significantly reduce total mosquito pupae (P = 0.07) in Matamoros, Mexico. The study also evaluated the efficacy of native Toxorhynchites moctezuma which preferentially colonized tire piles under vegetation cover in Brownsville, TX. Toxorhynchites moctezuma larvae significantly reduced total mosquito pupae, but the strength of control diminished over time.

  18. Mosquito biodiversity patterns around urban environments in South-central okinawa island, Japan.

    PubMed

    Hoshi, Tomonori; Imanishi, Nozomi; Higa, Yukiko; Chaves, Luis Fernando

    2014-12-01

    Okinawa is the largest, most urbanized, and densely populated island in the Ryukyus Archipelago, where mosquito species diversity has been thoroughly studied. However, the south-central Okinawa mosquito fauna has been relatively poorly studied. Here, we present results from a mosquito faunal survey in urban environments of Nishihara city, south-central Okinawa. Mosquitoes were sampled biweekly, from April 2007 to March 2008, at 3 different environments: a forest preserve, an animal farm, and a water reservoir. We employed 4 mosquito collection methods: 1) oviposition traps; 2) light traps; 3) sweep nets; and 4) larval surveys of tree holes, leaf axils, and artificial water containers. We collected a total of 568 adults and 10,270 larvae belonging to 6 genera and 13 species, including 6 species of medical importance: Aedes albopictus, Armigeres subalbatus, Anopheles Hyrcanus group, Culex bitaeniorhynchus, Cx. quinquefasciatus, and Cx. tritaeniorhynchus. Mosquito species composition was similar to data from previous studies in Okinawa Island. The flattening of the species accumulation curve suggests that our diversity sampling was exhaustive with light and oviposition traps, as well as the coincidence between the species richness we found in the field and estimates from the Chao2 index, a theoretical estimator of species richness based on species abundance. This study highlights the importance of combining several sampling techniques to properly characterize regional mosquito fauna and to monitor changes in the presence of mosquito species.

  19. Mosquito control insecticides: a probabilistic ecological risk assessment on drift exposures of naled, dichlorvos (naled metabolite) and permethrin to adult butterflies.

    PubMed

    Hoang, T C; Rand, G M

    2015-01-01

    A comprehensive probabilistic terrestrial ecological risk assessment (ERA) was conducted to characterize the potential risk of mosquito control insecticide (i.e., naled, it's metabolite dichlorvos, and permethrin) usage to adult butterflies in south Florida by comparing the probability distributions of environmental exposure concentrations following actual mosquito control applications at labeled rates from ten field monitoring studies with the probability distributions of butterfly species response (effects) data from our laboratory acute toxicity studies. The overlap of these distributions was used as a measure of risk to butterflies. The long-term viability (survival) of adult butterflies, following topical (thorax/wings) exposures was the environmental value we wanted to protect. Laboratory acute toxicity studies (24-h LD50) included topical exposures (thorax and wings) to five adult butterfly species and preparation of species sensitivity distributions (SSDs). The ERA indicated that the assessment endpoint of protection, of at least 90% of the species, 90% of the time (or the 10th percentile from the acute SSDs) from acute naled and permethrin exposures, is most likely not occurring when considering topical exposures to adults. Although the surface areas for adulticide exposures are greater for the wings, exposures to the thorax provide the highest potential for risk (i.e., SSD 10th percentile is lowest) for adult butterflies. Dichlorvos appeared to present no risk. The results of this ERA can be applied to other areas of the world, where these insecticides are used and where butterflies may be exposed. Since there are other sources (e.g., agriculture) of pesticides in the environment, where butterfly exposures will occur, the ERA may under-estimate the potential risks under real-world conditions.

  20. Increasing the Success of Adults from Diverse Populations.

    ERIC Educational Resources Information Center

    Sheckley, Barry G.; Keeton, Morris T.

    1995-01-01

    The following methods can increase the academic success of adults from diverse populations: focus on how educational circumstances are experienced by individuals, not broad groups; maximize time spent on tasks related to course/degree requirements; and reduce student costs in terms of time, money, frustration, and stress. (SK)

  1. Estimated Full Scale IQ in an Adult Heroin Addict Population.

    ERIC Educational Resources Information Center

    Chastain, Robert L.; And Others

    The research concerning intellectual functioning in addict populations has not addressed basic questions concerning why and how intelligence quotients (IQ) might be related to drug addiction. A study was undertaken to estimate intellectual functioning based upon a demographic profile for Wechsler Adult Intelligence Scale-Revised (WAIS-R) Full…

  2. Genetic elimination of dengue vector mosquitoes.

    PubMed

    Wise de Valdez, Megan R; Nimmo, Derric; Betz, John; Gong, Hong-Fei; James, Anthony A; Alphey, Luke; Black, William C

    2011-03-22

    An approach based on mosquitoes carrying a conditional dominant lethal gene (release of insects carrying a dominant lethal, RIDL) is being developed to control the transmission of dengue viruses by vector population suppression. A transgenic strain, designated OX3604C, of the major dengue vector, Aedes aegypti, was engineered to have a repressible female-specific flightless phenotype. This strain circumvents the need for radiation-induced sterilization, allows genetic sexing resulting in male-only releases, and permits the release of eggs instead of adult mosquitoes. OX3604C males introduced weekly into large laboratory cages containing stable target mosquito populations at initial ratios of 8.5-101 OX3604Ctarget eliminated the populations within 10-20 weeks. These data support the further testing of this strain in contained or confined field trials to evaluate mating competitiveness and environmental and other effects. Successful completion of the field trials should facilitate incorporation of this approach into area-wide dengue control or elimination efforts as a component of an integrated vector management strategy.

  3. Genotypic structure of a Drosophila population for adult locomotor activity

    SciTech Connect

    Grechanyi, G.V.; Korzun, V.M.

    1995-01-01

    Analysis of the variation of adult locomotor activity in four samples taken at different times from a natural population of Drosophila melanogaster showed that the total variation of this trait is relatively stable in time and has a substantial genetic component. Genotypic structure of the population for locomotor activity is characterized by the presence of large groups of genotypes with high and low values of this trait. A possible explanation for the presence of such groups in a population is cyclic density-dependent selection.

  4. Crowdsourcing Science to Promote Human Health: New Tools to Promote Sampling of Mosquito Populations by Citizen Scientists

    NASA Astrophysics Data System (ADS)

    Boger, R. A.; Low, R.; Jaroensutasinee, M.; Jaroensutasinee, K.; Sparrow, E. B.; Costosa, J. I.; Medina, J.; Randolph, G.

    2015-12-01

    GLOBE in Thailand and GLOBE in Africa independently developed citizen science protocols for collecting and analyzing mosquito larvae. These protocols have been piloted in several workshops and implemented in schools. Data collected have been used for several secondary, undergraduate and graduate student research studies. Over this past year, 2015, these protocols have been synthesized into one protocol that will be made available to the world-wide community through the GLOBE website (www.globe.gov). This new protocol is designed to be flexible in the mosquito species that can be collected and the types of environments sampled (e.g., containers in and around the house, ponds, irrigation ditches in a rice paddy field). Plans are underway to enable web-based data entry and mobile apps for data collection and submission. Once everything is finalized, a GLOBE field campaign will be initiated for citizen scientists to collect meaningful data on where different types of mosquito larvae are found and how the abundance and distribution is changing seasonally. To assist in the standardization of data collection and quality control, training slides are being developed and will be made available in early 2016. This will enable a wider participation of citizen scientists to participate in this effort to collect mosquito data by making it easier to become part of the GLOBE community. As with mosquito larvae, training slides are being created for hydrosphere, biosphere, atmosphere, and pedosphere GLOBE measurement protocols. The development of the mosquito protocol and the training slides are in direct response to the GLOBE community's desire to increase citizen science participation beyond primary and secondary schools, in observing and measuring environmental change.

  5. Population-regulating processes during the adult phase in flatfish

    NASA Astrophysics Data System (ADS)

    Rijnsdorp, A. D.

    Flatfish support major fisheries and the study of regulatory processes are of paramount importance for evaluating the resilience of the resource to exploitation. This paper reviews the evidence for processes operating during the adult phase that may 1. generate interannual variability in recruitment; 2. contribute to population regulation through density-dependent growth, density-dependent ripening of adults and density-dependent egg production. With regard to (1), there is evidence that in the adult phase processes do occur that may generate recruitment variability through variation in size-specific fecundity, contraction of spawning season, reduction in egg quality, change in sex ratio and size composition of the adult population. However, time series of recruitment do not provide support for this hypothesis. With regard to (2), there is ample evidence that exploitation of flatfish coincides with an increase in growth, although the mechanisms involved are not always clear. The presence of density-dependent growth in the adult phase of unexploited populations appears to be the most likely explanation in some cases. From the early years of exploitation of flatfish stocks inhabiting cold waters, evidence exists that adult fish do not spawn each year. Fecundity schedules show annual variations, but the available information suggests that size-specific fecundity is stable over a broad range of population abundance and may only decrease at high population abundance. The analysis is complicated by the possibility of a trade-off between egg numbers and egg size. Nevertheless, a density-dependent decrease in growth will automatically result in a decrease in absolute fecundity because of the reduced body size. The potential contribution of these regulatory effects on population regulation is explored. Results indicate that density-dependent ripening and absolute fecundity, mediated through density-dependent growth, may control recruitment at high levels of population

  6. Influence of Urban Landscapes on Population Dynamics in a Short-Distance Migrant Mosquito: Evidence for the Dengue Vector Aedes aegypti

    PubMed Central

    Hemme, Ryan R.; Thomas, Clayton L.; Chadee, Dave D.; Severson, David W.

    2010-01-01

    Background Dengue viruses are endemic across most tropical and subtropical regions. Because no proven vaccines are available, dengue prevention is primarily accomplished through controlling the mosquito vector Aedes aegypti. While dispersal distance is generally believed to be ∼100 m, patterns of dispersion may vary in urban areas due to landscape features acting as barriers or corridors to dispersal. Anthropogenic features ultimately affect the flow of genes affecting vector competence and insecticide resistance. Therefore, a thorough understanding of what parameters impact dispersal is essential for efficient implementation of any mosquito population suppression program. Population replacement and genetic control strategies currently under consideration are also dependent upon a thorough understanding of mosquito dispersal in urban settings. Methodology and Principal Findings We examined the effect of a major highway on dispersal patterns over a 2 year period. A. aegypti larvae were collected on the east and west sides of Uriah Butler Highway (UBH) to examine any effect UBH may have on the observed population structure in the Charlieville neighborhood in Trinidad, West Indies. A panel of nine microsatellites, two SNPs and a 710 bp sequence of mtDNA cytochrome oxidase subunit 1 (CO1) were used for the molecular analyses of the samples. Three CO1 haplotypes were identified, one of which was only found on the east side of the road in 2006 and 2007. AMOVA using mtCO1 and nuclear markers revealed significant differentiation between the east- and west-side collections. Conclusion and Significance Our results indicate that anthropogenic barriers to A. aegypti dispersal exist in urban environments and should be considered when implementing control programs during dengue outbreaks and population suppression or replacement programs. PMID:20300516

  7. Toxicity of white snakeroot (Ageratina altissima) compounds to adult and larval lifestages of the yellow fever mosquito, Aedes aegypt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because of increasing insecticide resistance, new pesticides are needed. Flowering plants have been the source of useful pesticides in the past. We studied 15 chemicals isolated from a poisonous pasture plant for activity against the yellow fever mosquito. We found that dehydrotremetone was effectiv...

  8. Study on Fungal Flora in the Midgut of the Larva and Adult of the Different Populations of the Malaria Vector Anopheles stephensi

    PubMed Central

    Tajedin, L; Hashemi, J; Abaei, MR; Hosseinpour, L; Rafei, F; Basseri, HR

    2009-01-01

    Background Many microorganisms in midgut of mosquito challenge with their host and also other pathogens present in midgut. The aim of this study was presence of non-pathogens microorganisms like fungal flora which may be crucial on interaction between vectors and pathogens. Methods: Different populations of Anopheles stephensi were reared in insectary and objected to determine fungal flora in their midguts. The midgut paunch of mosquito adults and larvae as well as breading water and larval food samples transferred on Subaru-dextrose agar, in order to detect the environment fungus. Results: Although four fungi, Aspergillus, Rhizopus, Geotrichum and Sacharomyces were found in the food and water, but only Aspiragilus observed in the midgut of larvae. No fungus was found in the midgut of adults. This is the first report on fungal flora in the midgut of the adults and larvae of An. stephensi and possible stadial transmission of fungi from immature stages to adults. Conclusion: The midgut environment of adults is not compatible for survivorship of fungi but the larval midgut may contain few fungi as a host or even pathogen. PMID:22808370

  9. Mosquitoes, models, and dengue.

    PubMed

    Lifson, A R

    1996-05-04

    In the last 10 years dengue has spread markedly through Latin America and the Caribbean (Dominican Republic, Jamaica, Barbados, Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Ecuador, Colombia, Venezuela, and Brazil). The mosquito Aedes aegypti has taken advantage of increased urbanization and crowding to transmit the dengue virus. The mosquito infests tires, cans, and water jars near dwellings. The female mosquito practices multiple, interrupted feeding. Thus, mosquito infesting and feeding practices facilitate dengue transmission in crowded conditions. Factors contributing to the spread of dengue include numbers of infected and susceptible human hosts, strain of dengue virus, size of mosquito population, feeding habits, time from infection to ability to transmit virus for both vector and host, likelihood of virus transmission from human to mosquito to human, and temperature (which affects vector distribution, size, feeding habits, and extrinsic incubation period). Public health models may use simulation models to help them plan or evaluate the potential impact of different intervention strategies and/or of environmental changes (e.g., global warming). Other factors contributing to the dengue epidemic are international travel, urbanization, population growth, crowding, poverty, a weakened public health infrastructure, and limited support for sustained disease control programs. Molecular epidemiology by nucleic acid sequence analysis is another sophisticated technique used to study infectious diseases. It showed that dengue type 3 isolated from Panama and Nicaragua in 1994 was identical to that responsible for the major dengue hemorrhagic fever epidemics in Sri Lanka and India in the 1980s. Public health officials must remember three priorities relevant to dengue and other emerging infections: the need to strengthen surveillance efforts, dedicated and sustained involvement in prevention and control needs at the local level, and a strong

  10. Impact of rapid urbanization on mosquitoes and their disease transmission potential in Accra and Tema, Ghana.

    PubMed

    Chinery, W A

    1995-06-01

    The total of 75 mosquito species recorded in Accra have declined to 28 species. Contributing factors to this decline and the reduction in prevalence of malaria and bancroftian filariasis in Accra presently include extensive water pollution and a fairly high daily mosquito mortality due to several factors including loss of natural adult resting places, use of mosquito repellents and the probable increase of Anopheles arabiensis population. Presently low yellow fever incidence is due inter alia to loss of its feral vectors and reduced intradomiciliary breeding of Aedes aegypti (L) although more common species like A. gambiae s.l., A. aegypti and C. p. quinquefasciatus could between them transmit many other arboviruses. However because of ready availability of human blood, spill-over of viruses from reservoir hosts to man will be rare. Ipso factor, malaria is the most common mosquito-borne disease with centripetal distribution of prevalence.

  11. Toxicity and residual action of the photoactivated compound, cyano-alpha-terthienyl, and its efficacy for reducing pre-imaginal populations of mosquitoes.

    PubMed

    Dosdall, L M; Galloway, M M; Arnason, J T

    1992-06-01

    The photoactivated compound, cyano-alpha-terthienyl (cyano-alpha-T), was highly toxic to pre-imagines of the mosquitoes Culex restuans, Cx. tarsalis and Culiseta inornata when synergized with piperonyl butoxide (PBO). Lethal concentrations for 50% mortality, determined during an outdoor trial using caged fourth-instar Culex spp. larvae, were 19.4, 15.4 and 12.9 g/ha at 24, 48 and 72 h after treatment, respectively. No residual activity of cyano-alpha-T was observed beyond 24 h following treatment. In artificial pool tests, greatest population reductions were achieved using dosages of 20 and 40 g/ha; statistically significant reductions were not observed following applications of 5 g/ha. Cyano-alpha-T plus PBO was more effective for reducing mosquito populations than alpha-terthienyl (alpha-T) plus PBO at comparable dosages, although it exhibited slightly lower insecticidal activity at a dosage of 20 g/ha than a formulation of Bacillus thuringiensis var. israelensis (Vectobac 12 AS, 0.12 ml/m2). Greatest effectiveness of cyano-alpha-T plus PBO was observed in pools with low organic content relative to pools high in organic content.

  12. Modelling and analysis of impulsive releases of sterile mosquitoes.

    PubMed

    Huang, Mingzhan; Song, Xinyu; Li, Jia

    2017-12-01

    To study the impact of releasing sterile mosquitoes on mosquito-borne disease transmissions, we propose two mathematical models with impulsive releases of sterile mosquitoes. We consider periodic impulsive releases in the first model and obtain the existence, uniqueness, and globally stability of a wild-mosquito-eradication periodic solution. We also establish thresholds for the control of the wild mosquito population by selecting the release rate and the release period. In the second model, the impulsive releases are determined by the closely monitored wild mosquito density, or the state feedback. We prove the existence of an order one periodic solution and find a relatively small attraction region, which ensures the wild mosquito population is under control. We provide numerical analysis which shows that a smaller release rate and more frequent releases are more efficient in controlling the wild mosquito population for the periodic releases, but an early release of sterile mosquitoes is more effective for the state feedback releases.

  13. Species composition and population dynamics of Aedes mosquitoes, potential vectors of arboviruses, at the container terminal of the autonomous port of Abidjan, Côte d’Ivoire

    PubMed Central

    Konan, Yao Lucien; Coulibaly, Zanakoungo Ibrahim; Koné, Atiuomounan Blaise; Ekra, Kouadio Daniel; Doannio, Julien Marie-Christian; Dosso, Mirielle; Odéhouri-Koudou, Paul

    2013-01-01

    An entomological survey of Aedes mosquitoes was initiated at the container terminal of the Autonomous Port of Abidjan in 2009 following the occurrence of two outbreaks of yellow fever in less than 10 years and dengue cases reported in 2008 among expatriates returning from Côte d’Ivoire (Ivory Coast). It was based on regular monitoring of ovitraps from July 2009 to June 2010. A total of 4,739 adult mosquitoes represented by four species of Aedes (97% of total) and one unexpected species of Culex (3%) were obtained. Aedes aegypti was dominant with 98% of total Aedes (n = 4,594). Its density variation was closely related to the amount of rainfall. The other species of Aedes were collected in the second half of the major rainy season including Ae. albopictus (1.17% of Aedes) and Ae. angustus (0.13%) whose presence was discovered for the first time in Côte d’Ivoire. PMID:23567057

  14. Mosquitoes established in Lhasa city, Tibet, China

    PubMed Central

    2013-01-01

    Background In 2009, residents of Lhasa city, Tibet Autonomous Region (TAR), China reported large numbers of mosquitoes and bites from these insects. It is unclear whether this was a new phenomenon, which species were involved, and whether these mosquitoes had established themselves in the local circumstances. Methods The present study was undertaken in six urban sites of Chengguan district Lhasa city, Tibet. Adult mosquitoes were collected by bed net trap, labor hour method and light trap in August 2009 and August 2012. The trapped adult mosquitoes were initially counted and identified according to morphological criteria, and a proportion of mosquitoes were examined more closely using a multiplex PCR assay. Results 907 mosquitoes of the Culex pipiens complex were collected in this study. Among them, 595 were females and 312 were males. There was no significant difference in mosquito density monitored by bed net trap and labor hour method in 2009 and 2012. Of 105 mosquitoes identified by multiplex PCR, 36 were pure mosquitoes (34.29%) while 69 were hybrids (65.71%). The same subspecies of Culex pipiens complex were observed by bed net trap, labor hour method and light trap in 2009 and 2012. Conclusion The local Culex pipiens complex comprises the subspecies Cx. pipiens pipiens, Cx. pipiens pallens, Cx. pipiens quinquefasciatus and its hybrids. Mosquitoes in the Cx. pipiens complex, known to be, potentially, vectors of periodic filariasis and encephalitis, are now present from one season to the next, and appear to be established in Lhasa City, TAR. PMID:24060238

  15. Effects of Cohabitation on the Population Performance and Survivorship of the Invasive Mosquito Aedes albopictus and the Resident Mosquito Aedes notoscriptus (Diptera: Culicidae) in Australia.

    PubMed

    Nicholson, J; Ritchie, S A; Russell, R C; Webb, C E; Cook, A; Zalucki, M P; Williams, C R; Ward, P; van den Hurk, A F

    2015-05-01

    The presence of Aedes albopictus (Skuse) in the Torres Strait of northern Australia increases the potential for colonization and establishment on the mainland. However, there is a possibility that native species that occupy the same habitats may influence the population performance of Ae. albopictus, potentially affecting the establishment of this species in Australia. Cohabitation experiments were performed with the endemic Aedes notoscriptus (Skuse), which has been found occupying the same larval habitats as Ae. albopictus in the Torres Strait and is the most widespread container-inhabiting Aedes species in Australia. The influence of environmental factors and cohabitation between the two species was examined using different climates, food resource levels, food resource types, and species densities. Survivorship proportions and a population performance index (λ') were calculated and compared. The consequences of increased Ae. notoscriptus densities were reduced survivorship and λ' for Ae. albopictus. Despite this, the mean λ' of Ae. albopictus and Ae. notoscriptus was consistently ≥ 1.06, indicating both species could increase under all conditions, potentially due to increasing conspecific densities negatively affecting Ae. notoscriptus. The outcomes from this study suggest that the preexisting presence of Ae. notoscriptus may not prevent the establishment of Ae. albopictus in Australia.

  16. The Prevalence of Tooth Wear in the Dutch Adult Population

    PubMed Central

    Wetselaar, Peter; Vermaire, Jan H.; Visscher, Corine M.; Lobbezoo, Frank; Schuller, Annemarie A.

    2016-01-01

    This study aimed to assess the prevalence of tooth wear in different age groups of the Dutch adult population and to determine this tooth wear distribution by gender, socioeconomic class, and type of teeth. Results were compared with the outcomes of a previous study in a comparable population. As part of a comprehensive investigation of the oral health of the general Dutch adult population in 2013, tooth wear was assessed among 1,125 subjects in the city of ‘s-Hertogenbosch. The data collected were subjected to stratified analysis by 5 age groups (25-34, 35-44, 45-54, 55-64, and 65-74 years), gender, socioeconomic class, and type of teeth. Tooth wear was assessed using a 5-point ordinal occlusal/incisal grading scale. The number of teeth affected was higher in older age groups. Men showed more tooth wear than women, and subjects with low socioeconomic status (low SES) showed on average higher scores than those with high SES. Tooth wear prevalence found in this study was higher in all age groups than in the previous study. The present study found prevalences of 13% for mild tooth wear and 80% for moderate tooth wear, leading to the conclusion that these are common conditions in the Dutch adult population. Severe tooth wear (prevalence 6%) may however be characterized as rare. A tendency was found for there to be more tooth wear in older age groups, in men as compared with women, in persons with lower SES, and in the present survey as compared with the previous one. PMID:27694757

  17. Species Composition and WNV Screening of Mosquitoes from Lagoons in a Wetland Area of the Algarve, Portugal

    PubMed Central

    Freitas, Ferdinando B.; Novo, Maria Teresa; Esteves, Aida; de Almeida, A. Paulo G.

    2012-01-01

    The aim of this study was to evaluate mosquito abundance, species diversity, larval and adult population dynamics in seven lagoons integrated in the wetland coastal system of the Algarve, Portugal, in the summer of 2007, as well as the screening of these for West Nile virus (WNV). WNV has been isolated from mosquitoes in this region, in the summer of 2004, next to the putative area of infection of two linked human WN cases. Adult mosquitoes were collected with CDC traps baited with CO2, and potential breeding sites were surveyed for immature stages. Morphological identification of 1,432 adult mosquitoes and 85 larvae revealed the presence of 10 species: Anopheles atroparvus, Anopheles algeriensis, Coquillettidia richiardii, Culex modestus, Culex pipiens, Culex theileri, Culex univittatus, Culiseta longiareolata, Aedes caspius, and Aedes detritus. Adult mosquito peak densities were recorded in July, contrasting with null larval breeding in the same month in the surveyed biotopes. Most abundant species were C. pipiens (52%), C. theileri (29%), and A. caspius (11%). Lagoon Salgados and Quinta das Salinas, exhibited the highest similarity of culicid fauna, despite being most distant from each other, Female mosquitoes (1,249 specimens) screened by RT-PCR, did not reveal WNV products. However, previous detection of WNV activity in this area, susceptible to re-introductions, demands for continued vigilance. PMID:22347862

  18. Morphometric Evaluation of Adult Acromion Process in North Indian Population

    PubMed Central

    Vasudeva, Neelam

    2017-01-01

    Introduction Dimensions of acromion process are important to show linkage to the shoulder girdle pathologies. Also morphometric analysis of acromion process would be helpful for surgeons while performing surgical procedures on the shoulder joint. Aim The purpose of this present study was to observe the detailed morphometric evaluation of adult acromion processes in North Indian population because different morphometric dimensions play an important role in various disorders of the shoulder, particularly sub acromial impingement syndrome. Materials and Methods Two hundred adult dry scapulae from the osteology museum of MAMC, New Delhi, were obtained for evaluation of various measurement of acromion process. The length, width, thickness of acromion, coraco-acromial (C-A) distance and acromio-glenoid (Ac-g) distance were measured. The measurements were compared with other osteological studies performed on different population group. Data was analysed using SPSS version 12.0 and mean values with standard deviation for each dimension were presented. Results The mean values of each measurement were: length: 41.007 mm; width: 21.82 mm; thickness: 6.58 mm; C-A distance: 28.34 mm and Ac-g distance: 26.21 mm. Conclusion It is expected that various dimensions of adult acromion process will serve as a reference base and will assist the surgeon in the approach to be used and precision of the operative technique. So, the study will provide a vital support for planning and executing acromioplasty in the treatment of impingement syndrome. PMID:28273959

  19. Assessing the impacts of truck based ultra-low volume applications of mosquito adulticides on honey bees (Apis mellifera)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mosquito control reduces populations of mosquitoes to minimize the risk of mosquito-borne diseases. As part of an integrated approach to mosquito control, application of adulticides can be effective in rapidly reducing mosquito populations during times of high arbovirus transmission. However, impact...

  20. Pre-West Nile virus outbreak: perceptions and practices to prevent mosquito bites and viral encephalitis in the United States.

    PubMed

    Herrington, James E

    2003-01-01

    Mosquitoes can transmit over 100 of the viruses that can cause encephalitis, meningitis, and hemorrhagic disease in humans (Chin 2000; Gubler 1996; Monath 1989). While much is known about the ecology, epidemiology, and clinical manifestations of the arboviral encephalitides (Campbell et al. 2002; Centers for Disease Control and Prevention 1997; Gubler 1998; Hayes 1989; Hubálek and Halouzka 1999), little empirical research exists regarding the U.S. population's knowledge of mosquitoes and arboviral encephalitis, particularly prior to the U.S. outbreak of West Nile virus (WNV) in 1999. A nationally representative 55-item survey instrument was successfully administered to 1,500 adults in the United States and an additional 250 adults in six states in the Northeast (Connecticut, Delaware, New Jersey, New York, Pennsylvania, and Rhode Island) regarding mosquitoes and mosquito-borne viral encephalitis. A summary outcome measure for mosquito bite prevention was created. Analyses revealed that the following were statistically significant predictors of behaviors taken to prevent mosquito bites: being concerned about being bitten by mosquitoes, perceived effectiveness of staying indoors in late afternoon and early evening was protective, perceived effectiveness that mosquito repellent is not harmful to health, owning dogs and/or cats as pets, being married, and being > or = 18-44 years old. Being concerned about being bitten by mosquitoes was the most robust predictor of behavioral action to prevent mosquito bites (OR = 7.3; 95% CI = 4.3, 12.2). Observed misperceptions and inadequate knowledge regarding insect repellents suggest increased promotion of the safety and efficacy of DEET-containing insect repellents is warranted.

  1. Nightmares: Risk Factors Among the Finnish General Adult Population

    PubMed Central

    Sandman, Nils; Valli, Katja; Kronholm, Erkki; Revonsuo, Antti; Laatikainen, Tiina; Paunio, Tiina

    2015-01-01

    Study Objectives: To identify risk factors for experiencing nightmares among the Finnish general adult population. The study aimed to both test whether previously reported correlates of frequent nightmares could be reproduced in a large population sample and to explore previously unreported associations. Design: Two independent cross-sectional population surveys of the National FINRISK Study. Setting: Age- and sex-stratified random samples of the Finnish population in 2007 and 2012. Participants: A total of 13,922 participants (6,515 men and 7,407 women) aged 25–74 y. Interventions: N/A. Measurements and results: Nightmare frequency as well as several items related to socioeconomic status, sleep, mental well-being, life satisfaction, alcohol use, medication, and physical well-being were recorded with a questionnaire. In multinomial logistic regression analysis, a depression-related negative attitude toward the self (odds ratio [OR] 1.32 per 1-point increase), insomnia (OR 6.90), and exhaustion and fatigue (OR 6.86) were the strongest risk factors for experiencing frequent nightmares (P < 0.001 for all). Sex, age, a self-reported impaired ability to work, low life satisfaction, the use of antidepressants or hypnotics, and frequent heavy use of alcohol were also strongly associated with frequent nightmares (P < 0.001 for all). Conclusions: Symptoms of depression and insomnia were the strongest predictors of frequent nightmares in this dataset. Additionally, a wide variety of factors related to psychological and physical well-being were associated with nightmare frequency with modest effect sizes. Hence, nightmare frequency appears to have a strong connection with sleep and mood problems, but is also associated with a variety of measures of psychological and physical well-being. Citation: Sandman N, Valli K, Kronholm E, Revonsuo A, Laatikainen T, Paunio T. Nightmares: risk factors among the finnish general adult population. SLEEP 2015;38(4):507–514. PMID:25325474

  2. Establishment of Aedes aegypti (L.) in mountainous regions in Mexico: Increasing number of population at risk of mosquito-borne disease and future climate conditions.

    PubMed

    Equihua, Miguel; Ibáñez-Bernal, Sergio; Benítez, Griselda; Estrada-Contreras, Israel; Sandoval-Ruiz, César A; Mendoza-Palmero, Fredy S

    2017-02-01

    The study was conducted in the central region of Veracruz Mexico, in the metropolitan area of Xalapa. It is a mountainous area where Aedes aegypti (L.) is not currently endemic. An entomological survey was done along an elevation gradient using the Ae. aegypti occurrences at different life cycle stages. Seven sites were sampled and a total of 24 mosquito species were recorded: 9 species were found in urban areas, 18 in non-urban areas with remnant vegetation, and 3 occurred in both environments. Ae. aegypti was found only in the urban areas, usually below 1200m a.s.l., but in this study was recorded for the first time at 1420m a.s.l. These occurrences, together with additional distribution data in the state of Veracruz were used to developed species distribution models using Maxlike software in R to identify the current projected suitable areas for the establishment of this vector and the human populations that might be affected by dengue transmission at higher elevations. Its emergence in previously unsuitable places appears to be driven by both habitat destruction and biodiversity loss associated with biotic homogenization. A border study using data from the edges of the vector's distribution might allow sensitive monitoring to detect any changes in this mosquito's distribution pattern, and any changes in the anthropic drivers or climate that could increase transmission risk.

  3. Functional significance of mononuclear phagocyte populations generated through adult hematopoiesis

    PubMed Central

    Gutknecht, Michael F.; Bouton, Amy H.

    2014-01-01

    Tissue homeostasis requires a complete repertoire of functional macrophages in peripheral tissues. Recent evidence indicates that many resident tissue macrophages are seeded during embryonic development and persist through adulthood as a consequence of localized proliferation. Mononuclear phagocytes are also produced during adult hematopoiesis; these cells are then recruited to sites throughout the body, where they function in tissue repair and remodeling, resolution of inflammation, maintenance of homeostasis, and disease progression. The focus of this review is on mononuclear phagocytes that comprise the nonresident monocyte/macrophage populations in the body. Key features of monocyte differentiation are presented, focusing primarily on the developmental hierarchy that is established through this process, the markers used to identify discrete cell populations, and novel, functional attributes of these cells. These features are then explored in the context of the tumor microenvironment, where mononuclear phagocytes exhibit extensive plasticity in phenotype and function. PMID:25225678

  4. Using evolutionary costs to enhance the efficacy of malaria control via genetically manipulated mosquitoes.

    PubMed

    Koella, Jacob C; Zaghloul, Lamia

    2008-11-01

    An earlier mathematical model exploring the use of genetically manipulated mosquitoes for malaria control suggested that the prevalence of malaria is reduced significantly only if almost all mosquitoes become completely resistant to malaria. Central to the model was the 'cost of resistance': the reduction of a resistant mosquito's evolutionary fitness in comparison with a sensitive one's. Here, we consider the possibility of obtaining more optimistic outcomes by taking into account the epidemiological (in addition to the evolutionary) consequences of a cost of resistance that decreases the life-span of adult mosquitoes (the most relevant parameter for the parasite's epidemiology). There are two main results. First, if despite its cost, resistance is fixed in the population, increasing the cost of resistance decreases the intensity of transmission. However, this epidemiological effect is weak if resistance is effective enough to be considered relevant for control. Second, if the cost of resistance prevents its fixation, increasing it intensifies transmission. Thus, the epidemiological effect of the cost of resistance cannot compensate for the lower frequency of resistant mosquitoes in the population. Overall, our conclusion remains pessimistic: so that genetic manipulation can become a promising method of malaria control, we need techniques that enable almost all mosquitoes to be almost completely resistant to infection.

  5. Community factors associated with malaria prevention by mosquito nets: an exploratory study in rural Burkina Faso.

    PubMed

    Okrah, Jane; Traoré, Corneille; Palé, Augustin; Sommerfeld, Johannes; Müller, Olaf

    2002-03-01

    Malaria-related knowledge, attitudes and practices (KAP) were examined in a rural and partly urban multiethnic population of Kossi province in north-western Burkina Faso prior to the establishment of a local insecticide-treated bednet (ITN) programme. Various individual and group interviews were conducted, and a structured questionnaire was administered to a random sample of 210 heads of households in selected villages and the provincial capital of Nouna. Soumaya, the local illness concept closest to the biomedical term malaria, covers a broad range of recognized signs and symptoms. Aetiologically, soumaya is associated with mosquito bites but also with a number of other perceived causes. The disease entity is perceived as a major burden to the community and is usually treated by both traditional and western methods. Malaria preventive practices are restricted to limited chloroquine prophylaxis in pregnant women. Protective measures against mosquitoes are, however, widespread through the use of mosquito nets, mosquito coils, insecticide sprays and traditional repellents. Mosquito nets are mainly used during the rainy season and most of the existing nets are used by adults, particularly heads of households. Mosquito nets treated with insecticide (ITN) are known to the population through various information channels. People are willing to treat existing nets and to buy ITNs, but only if such services would be offered at reduced prices and in closer proximity to the households. These findings have practical implications for the design of ITN programmes in rural areas of sub-Saharan Africa (SSA).

  6. Suppression of a Field Population of Aedes aegypti in Brazil by Sustained Release of Transgenic Male Mosquitoes.

    PubMed

    Carvalho, Danilo O; McKemey, Andrew R; Garziera, Luiza; Lacroix, Renaud; Donnelly, Christl A; Alphey, Luke; Malavasi, Aldo; Capurro, Margareth L

    2015-01-01

    The increasing burden of dengue, and the relative failure of traditional vector control programs highlight the need to develop new control methods. SIT using self-limiting genetic technology is one such promising method. A self-limiting strain of Aedes aegypti, OX513A, has already reached the stage of field evaluation. Sustained releases of OX513A Ae. aegypti males led to 80% suppression of a target wild Ae. aegypti population in the Cayman Islands in 2010. Here we describe sustained series of field releases of OX513A Ae. aegypti males in a suburb of Juazeiro, Bahia, Brazil. This study spanned over a year and reduced the local Ae. aegypti population by 95% (95% CI: 92.2%-97.5%) based on adult trap data and 81% (95% CI: 74.9-85.2%) based on ovitrap indices compared to the adjacent no-release control area. The mating competitiveness of the released males (0.031; 95% CI: 0.025-0.036) was similar to that estimated in the Cayman trials (0.059; 95% CI: 0.011-0.210), indicating that environmental and target-strain differences had little impact on the mating success of the OX513A males. We conclude that sustained release of OX513A males may be an effective and widely useful method for suppression of the key dengue vector Ae. aegypti. The observed level of suppression would likely be sufficient to prevent dengue epidemics in the locality tested and other areas with similar or lower transmission.

  7. Suppression of a Field Population of Aedes aegypti in Brazil by Sustained Release of Transgenic Male Mosquitoes

    PubMed Central

    Garziera, Luiza; Lacroix, Renaud; Donnelly, Christl A.; Alphey, Luke; Malavasi, Aldo; Capurro, Margareth L.

    2015-01-01

    The increasing burden of dengue, and the relative failure of traditional vector control programs highlight the need to develop new control methods. SIT using self-limiting genetic technology is one such promising method. A self-limiting strain of Aedes aegypti, OX513A, has already reached the stage of field evaluation. Sustained releases of OX513A Ae. aegypti males led to 80% suppression of a target wild Ae. aegypti population in the Cayman Islands in 2010. Here we describe sustained series of field releases of OX513A Ae. aegypti males in a suburb of Juazeiro, Bahia, Brazil. This study spanned over a year and reduced the local Ae. aegypti population by 95% (95% CI: 92.2%-97.5%) based on adult trap data and 81% (95% CI: 74.9-85.2%) based on ovitrap indices compared to the adjacent no-release control area. The mating competitiveness of the released males (0.031; 95% CI: 0.025-0.036) was similar to that estimated in the Cayman trials (0.059; 95% CI: 0.011 – 0.210), indicating that environmental and target-strain differences had little impact on the mating success of the OX513A males. We conclude that sustained release of OX513A males may be an effective and widely useful method for suppression of the key dengue vector Ae. aegypti. The observed level of suppression would likely be sufficient to prevent dengue epidemics in the locality tested and other areas with similar or lower transmission. PMID:26135160

  8. Malathion resistance and prevalence of the malathion carboxylesterase mechanism in populations of mosquito vectors of disease in Sri Lanka.

    PubMed Central

    Karunaratne, S. H.; Hemingway, J.

    2001-01-01

    OBJECTIVE: To determine the levels of malathion resistance and prevalence of the malathion carboxylesterase mechanism among mosquitoes in Sri Lanka. METHODS: Bioassays were carried out using WHO-recommended methods on samples of the following Sri Lankan mosquito vectors: Culex quinquefasciatus, C. tritaeniorhynchus, C gelidus, Anopheles culicifacies B, A. subpictus, Aedes aegypti and A. albopictus. FINDINGS Malathion-specific carboxylesterase mechanisms were found in A. culicifaies and A. subpictus, both giving high rates of insecticide metabolism. In contrast, malathion resistance in C. quinquefasciatus and C. tritaeniorhynchus is linked to broad-spectrum resistance to organophosphorus compounds due to elevated levels of esterases that sequester malaoxon, but are unable to metabolize malathion. CONCLUSIONS: Resistance among the Anophelesspp. must have occurred as a direct result of antimalarial activities, since malathion use in Sri Lanka is limited to public health treatments. In contrast, resistance among Culex spp. has resulted from large-scale use of the organophosphorus insecticide group as larvicides for filariasis control and on rice paddy, where C tritaeniorhynchus predominantly breeds, for agricultural purposes. PMID:11731814

  9. [Alimentation dependent health disorders among adult population of Bashkortostan Republic and their relation with nutritional traits].

    PubMed

    Takaev, R M; Kondrova, N S; Baĭkina, I M; Larionova, T K

    2008-01-01

    The authors demonstrated relationship between alimentation dependent diseases among adult population of the Republic and nutritional traits of the population, defined major directions of program to optimize nutrition of the population.

  10. Predictors of Septic Arthritis in the Adult Population.

    PubMed

    Borzio, Robert; Mulchandani, Neil; Pivec, Robert; Kapadia, Bhaveen H; Leven, Dante; Harwin, Steven F; Urban, William P

    2016-07-01

    Septic arthritis is a devastating condition; well-established criteria for diagnosis exist in the pediatric population, but not for adults. This study evaluated patient factors and laboratory parameters that may be associated with the diagnosis of septic arthritis in adults. A total of 458 knee aspirates for suspected septic arthritis were evaluated with serum and synovial leukocyte counts and differentials as well as Kocher criteria for pediatric septic arthritis. Twenty-two patients (4.8%) had septic arthritis confirmed by a positive synovial fluid culture. Erythrocyte sedimentation rate (ESR) and serum white blood cell (WBC) counts were not statistically different between the 2 groups, with 64% of septic arthritis patients having a normal serum WBC count and 77% being afebrile. Mean synovial fluid WBC count was 26,758 cells/µL and 70,581 cells/µL in the nonseptic and septic groups, respectively. The likelihood ratio for a synovial fluid WBC count greater than 65,000 cells/µL was 2.8 (95% confidence interval, 1.2-6.7). Evaluation receiver operating characteristic curves using synovial WBC counts resulted in a significant area under the curve of 0.66 (P=.02). To achieve 90% specificity, a WBC cutoff of 64,000 cells/µL was required with a corresponding sensitivity of 40%. There was no significant difference in the synovial cell differential of 80% vs 90% in diagnosing infection. Synovial fluid WBC count greater than 64,000 cells/µL yielded the optimal combination of sensitivity and specificity. Polymorphonuclear leukocytes, ESR, serum WBC count, fever, and weight-bearing status were not significant predictors of septic arthritis. This study demonstrates the limited utility of Kocher criteria in the adult population and the importance of synovial leukocyte counts. [Orthopedics. 2016; 39(4):e657-e663.].

  11. Spatial and temporal distribution of mosquitoes in underground storm drain systems in Orange County, California.

    PubMed

    Su, Tianyun; Webb, James P; Meyer, Richard P; Mulla, Mir S

    2003-06-01

    Underground storm drain systems in urban areas of Orange County include thousands of miles of gutters and underground pipelines, plus hundreds of thousands of catch basins and manhole chambers, all of which drain runoff water from residential, business and commercial establishments as well as highways and streets. These systems serve as major developmental and resting sites for anthropophilic and zoophilic mosquitoes. Investigations on spatial and temporal distribution of mosquitoes in these systems were conducted during November 1999 to October 2001. Immature mosquitoes were sampled by dipper or dipping net and adult mosquitoes by non-attractive CDC traps in manhole chambers, catch basins and a large drain. Culex quinquefasciatus Say prevailed at all 15 structures of the study in 4 cities of Orange County as the predominant species (> 99.9%). Larvae and pupae were present from April to October, peaking from May to September. The population density of adults was the lowest in February with 2 peaks of abundance occurring from May to July and from September to October. Manhole chambers and catch basins harbored more mosquitoes than did the large drain. Minimum and maximum temperatures during a 24 h sampling period was an important factor influencing adult mosquito activity and catches; more mosquitoes were caught in traps when it was warmer, especially when the minimum temperatures were higher. The proportion of females to males in general increased during winter and early spring an ddeclined during summer. The proportion of gravid females to empty females was higher during the winter than in summer. Other dipteran taxa such as psychodid moth flies and chironomid midges exhibited somewhat similar seasonal patterns as did mosquito populations. Average water temperature was relatively stable throughout the year, and water quality in underground drain systems was characterized by low dissolved oxygen, coupled with above normal electrical conductivity and salinity levels

  12. Young adults' trajectories of Ecstasy use: a population based study.

    PubMed

    Smirnov, Andrew; Najman, Jake M; Hayatbakhsh, Reza; Plotnikova, Maria; Wells, Helene; Legosz, Margot; Kemp, Robert

    2013-11-01

    Young adults' Ecstasy use trajectories have important implications for individual and population-level consequences of Ecstasy use, but little relevant research has been conducted. This study prospectively examines Ecstasy trajectories in a population-based sample. Data are from the Natural History Study of Drug Use, a retrospective/prospective cohort study conducted in Australia. Population screening identified a probability sample of Ecstasy users aged 19-23 years. Complete data for 30 months of follow-up, comprising 4 time intervals, were available for 297 participants (88.4% of sample). Trajectories were derived using cluster analysis based on recent Ecstasy use at each interval. Trajectory predictors were examined using a generalized ordered logit model and included Ecstasy dependence (World Mental Health Composite International Diagnostic Instrument), psychological distress (Hospital Anxiety Depression Scale), aggression (Young Adult Self Report) and contextual factors (e.g. attendance at electronic/dance music events). Three Ecstasy trajectories were identified (low, intermediate and high use). At its peak, the high-use trajectory involved 1-2 days Ecstasy use per week. Decreasing frequency of use was observed for intermediate and high-use trajectories from 12 months, independently of market factors. Intermediate and high-use trajectory membership was predicted by past Ecstasy consumption (>70 pills) and attendance at electronic/dance music events. High-use trajectory members were unlikely to have used Ecstasy for more than 3 years and tended to report consistently positive subjective effects at baseline. Given the social context and temporal course of Ecstasy use, Ecstasy trajectories might be better understood in terms of instrumental rather than addictive drug use patterns.

  13. Population Structure and Distribution Patterns of the Sibling Mosquito Species Culex pipiens and Culex torrentium (Diptera: Culicidae) Reveal Different Evolutionary Paths

    PubMed Central

    Werblow, Antje; Klimpel, Sven; Bolius, Sarah; Dorresteijn, Adriaan W. C.; Sauer, Jan; Melaun, Christian

    2014-01-01

    Nowadays a number of endemic mosquito species are known to possess vector abilities for various diseases, as e.g. the sibling species Culex pipiens and Culex torrentium. Due to their morphological similarity, ecology, distribution and vector abilities, knowledge about these species' population structure is essential. Culicidae from 25 different sampling sites were collected from March till October 2012. All analyses were performed with aligned cox1 sequences with a total length of 658 bp. Population structure as well as distribution patterns of both species were analysed using molecular methods and different statistical tests like distance based redundancy analysis (dbDRA), analysis of molecular variances (AMOVA) or McDonald & Kreitman test and Tajima's D. Within both species, we could show a genetic variability among the cox1 fragment. The construction of haplotype networks revealed one dominating haplotype for Cx. pipiens, widely distributed within Germany and a more homogeneous pattern for Cx. torrentium. The low genetic differences within Cx. pipiens could be a result of an infection with Wolbachia which can induce a sweep through populations by passively taking the also maternally inherited mtDNA through the population, thereby reducing the mitochondrial diversity as an outcome of reproductive incompatibility. Pairwise population genetic differentiation (FST) ranged significantly from moderate to very great between populations of Cx. pipiens and Cx. torrentium. Analyses of molecular variances revealed for both species that the main genetic variability exists within the populations (Cx. pipiens [88.38%]; Cx. torrentium [66.54%]). Based on a distance based redundancy analysis geographical origin explained a small but significant part of the species' genetic variation. Overall, the results confirm that Cx. pipiens and Cx. torrentium underlie different factors regarding their mitochondrial differentiation, which could be a result of endosymbiosis, dispersal

  14. Age and Time Population Differences: Young Adults, Gen Xers, and Millennials

    ERIC Educational Resources Information Center

    Menard, Lauren A.

    2013-01-01

    Age and Time disparities in young adult research populations are common because young adults are defined by varying age spans; members of Generation X and Millennial generations may both be considered young adults; study years vary, affecting populations; and qualitative methods with limited age/year samples are frequently utilized. The current…

  15. Weak larval competition between the invasive mosquito Aedes japonicus japonicus (Diptera: Culicidae) and three resident container-inhabiting mosquitoes in the laboratory.

    PubMed

    Hardstone, Melissa C; Andreadis, Theodore G

    2012-03-01

    The spread of exotic mosquito species into new environments can introduce shifts in mosquito populations and potentially alter public health risks to mosquito-borne diseases. The successful establishment of exotic species may occur due to their competitive advantage over other cohabitating species. We hypothesized that the recently introduced exotic mosquito Aedes japonicus japonicus (Theobald) would be a more effective competitor than Aedes atropalpus (Coquillett) and Aedes triseriatus (Say), and an equal competitor to Culex pipiens (L.) based on larval abundance data within tire habitats. Impacts of competition were measured using the larval developmental rate and survival of larvae, adult mortality, wing length, and sex ratio. We found that intraspecific competition acted strongest against Ae. japonicus versus the other three resident mosquito species by delaying larval development and increasing adult mortality. Interspecific competition was generally weak and significant main effects were only detected for species and density. Overall, our results show that larval competition between Ae. japonicus and the three resident species was weak when present, indicating that other ecological or behavioral factors may be influencing the invasion success for Ae. japonicus in North America.

  16. Population Genetics of Two Key Mosquito Vectors of Rift Valley Fever Virus Reveals New Insights into the Changing Disease Outbreak Patterns in Kenya

    PubMed Central

    Tchouassi, David P.; Bastos, Armanda D. S.; Sole, Catherine L.; Diallo, Mawlouth; Lutomiah, Joel; Mutisya, James; Mulwa, Francis; Borgemeister, Christian; Sang, Rosemary; Torto, Baldwyn

    2014-01-01

    Rift Valley fever (RVF) outbreaks in Kenya have increased in frequency and range to include northeastern Kenya where viruses are increasingly being isolated from known (Aedes mcintoshi) and newly-associated (Ae. ochraceus) vectors. The factors contributing to these changing outbreak patterns are unclear and the population genetic structure of key vectors and/or specific virus-vector associations, in particular, are under-studied. By conducting mitochondrial and nuclear DNA analyses on >220 Kenyan specimens of Ae. mcintoshi and Ae. ochraceus, we uncovered high levels of vector complexity which may partly explain the disease outbreak pattern. Results indicate that Ae. mcintoshi consists of a species complex with one of the member species being unique to the newly-established RVF outbreak-prone northeastern region of Kenya, whereas Ae. ochraceus is a homogeneous population that appears to be undergoing expansion. Characterization of specimens from a RVF-prone site in Senegal, where Ae. ochraceus is a primary vector, revealed direct genetic links between the two Ae. ochraceus populations from both countries. Our data strongly suggest that unlike Ae. mcintoshi, Ae. ochraceus appears to be a relatively recent, single 'introduction' into Kenya. These results, together with increasing isolations from this vector, indicate that Ae. ochraceus will likely be of greater epidemiological importance in future RVF outbreaks in Kenya. Furthermore, the overall vector complexity calls into question the feasibility of mosquito population control approaches reliant on genetic modification. PMID:25474018

  17. Spatial model for transmission of mosquito-borne diseases

    NASA Astrophysics Data System (ADS)

    Kon, Cynthia Mui Lian; Labadin, Jane

    2015-05-01

    In this paper, a generic model which takes into account spatial heterogeneity for the dynamics of mosquito-borne diseases is proposed. The dissemination of the disease is described by a system of reaction-diffusion partial differential equations. Host human and vector mosquito populations are divided into susceptible and infectious classes. Diffusion is considered to occur in all classes of both populations. Susceptible humans are infected when bitten by infectious mosquitoes. Susceptible mosquitoes bite infectious humans and become infected. The biting rate of mosquitoes is considered to be density dependent on the total human population in different locations. The system is solved numerically and results are shown.

  18. Diversity and ecology survey of mosquitoes potential vectors in Belgian equestrian farms: A threat prevention of mosquito-borne equine arboviruses.

    PubMed

    Boukraa, Slimane; de La Grandiere, Maria A; Bawin, Thomas; Raharimalala, Fara N; Zimmer, Jean-Yves; Haubruge, Eric; Thiry, Etienne; Francis, Frédéric

    2016-02-01

    Emergence of West Nile Virus was recently recorded in several European countries, which can lead to severe health problems in horse populations. Europe is also at risk of introduction of mosquito-borne equine alphavirus from Americas. Prevention of these arboviruses requires a clear understanding of transmission cycles, especially their vectors. To characterize mosquito fauna, their ecology and identify potential vectors of equine arboviruses in Belgium, entomological surveys of six equestrian farms located in the Wolloon Region were conducted during 2011-2012. The harvest of mosquitoes was based on larval sampling (272 samples from 111 breeding sites) and monthly adults trapping (CO2-baited traps, Mosquito Magnet Liberty Plus). Among 51,493 larvae and 319 adult mosquitoes collected, morphological identification showed the presence of 11 species: Anopheles claviger (Meigen), An. maculipennis s.l. (Meigen), An. plumbeus (Stephens), Culex hortensis (Ficalbi), Cx. territans (Walker), Cx. pipiens s.l. L., Cx. torrentium (Martini), Coquillettidia richiardii (Ficalbi), Culiseta annulata (Schrank), Aedes cantans (Meigen), Ae. geniculatus (Olivier). Molecular identification of Cx. pipiens species complex allowed the detection of three molecular forms, Pipiens (92.3%), Molestus (4.6%) and Hybrid (3.1%). Larvae of Cx. pipiens sl and Cx. torrentium were omnipresent and the most abundant species. Water troughs, ponds and slurry (liquid manure) were the most favorable breeding sites of mosquito larvae. Based upon behavior and ecology of the identified mosquito species, Studied Belgian equestrian farms seem to provide a suitable environment and breeding sites for the proliferation of potential vectors of arboviruses and those being a real nuisance problem for horses and neighboring inhabitants.

  19. Life and health satisfaction in the adult population of Iran

    PubMed Central

    2016-01-01

    OBJECTIVES Increasing interest has emerged in the use of subjective well-being as a development indicator and for the evaluation of public policies. The aim of this study was to assess life and health satisfaction and their determinants in the adult population of Iran. METHODS We conducted a survey of a sample of 3,150 adults at least 18 years of age in Tehran, the capital of Iran. The subjects were selected using a stratified random sampling method, and they were interviewed face-to-face at their usual residence by trained interviewers. Life satisfaction was used as a measure of subjective well-being. We used ordinary least square regression models to assess the associations of life and health satisfaction with socio-demographic variables. RESULTS On a 0-10 scale, the mean (standard deviation) scores for life and health satisfaction were 6.93 (2.54) and 7.18 (1.97), respectively. The average score for life satisfaction in females was 0.52 points higher than in males. A U-shaped relationship was found between age and life satisfaction, with respondents 35 to 44 years of age having the lowest average level of life satisfaction. Satisfaction with life and health among divorced respondents was significantly lower than among never-married and married participants. The scores for life satisfaction in respondents who rated their health status as poor were 3.83 points lower than in those who rated their health status as excellent. CONCLUSIONS The majority of the population of Tehran was satisfied with their life and health. Self-rated health status had the greatest impact on life satisfaction. PMID:27809456

  20. Spatio-temporal Modeling of Mosquito Distribution

    NASA Astrophysics Data System (ADS)

    Dumont, Y.; Dufourd, C.

    2011-11-01

    We consider a quasilinear parabolic system to model mosquito displacement. In order to use efficiently vector control tools, like insecticides, and mechanical control, it is necessary to provide density estimates of mosquito populations, taking into account the environment and entomological knowledges. After a brief introduction to mosquito dispersal modeling, we present some theoretical results. Then, considering a compartmental approach, we get a quasilinear system of PDEs. Using the time splitting approach and appropriate numerical methods for each operator, we construct a reliable numerical scheme. Considering vector control scenarii, we show that the environment can have a strong influence on mosquito distribution and in the efficiency of vector control tools.

  1. Energetic cost of insecticide resistance in Culex pipiens mosquitoes.

    PubMed

    Rivero, A; Magaud, A; Nicot, A; Vézilier, J

    2011-05-01

    The extensive use of insecticides to control vector populations has lead to the widespread development of different mechanisms of insecticide resistance. Mutations that confer insecticide resistance are often associated to fitness costs that prevent them from spreading to fixation. In vectors, such fitness costs include reductions in preimaginal survival, adult size, longevity, and fecundity. The most commonly invoked explanation for the nature of such pleiotropic effects of insecticide resistance is the existence of resource-based trade-offs. According to this hypothesis, insecticide resistance would deplete the energetic stores of vectors, reducing the energy available for other biological functions and generating trade-offs between insecticide resistance and key life history traits. Here we test this hypothesis by quantifying the energetic resources (lipids, glycogen, and glucose) of larvae and adult females of the mosquito Culex pipiens L. resistant to insecticides through two different mechanisms: esterase overproduction and acetylcholinesterase modification. We find that, as expected from trade-off theory, insecticide resistant mosquitoes through the overproduction of esterases contain on average 30% less energetic reserves than their susceptible counterparts. Acetylcholinesterase-modified mosquitoes, however, also showed a significant reduction in energetic resources (20% less). We suggest that, in acetylcholinesterase-modified mosquitoes, resource depletion may not be the result of resource-based trade-offs but a consequence of the hyperactivation of the nervous system. We argue that these results not only provide a mechanistic explanation for the negative pleiotropic effects of insecticide resistance on mosquito life history traits but also can have a direct effect on the development of parasites that depend on the vector's energetic reserves to fulfil their own metabolic needs.

  2. Bioefficacy of crude extract of Cyperus aromaticus (Family: Cyperaceae ) cultured cells, against Aedes aegypti and Aedes albopictus mosquitoes

    PubMed Central

    Kamiabi, Fatemeh; Jaal, Zairi; Keng, Chan Lai

    2013-01-01

    ratio of the adult population either parental or F1 generation of the Aedes mosquito species was not significantly affected by the EI50 dosage of the crude extract of C. aromaticus cultured P4 cells. A significant decrease in the wing length of the treated adult (female and male) of Aedes aegypti as well as the treated female of Ae. albopictus were observed. Longevity of the adult female of the parental generation of both Aedes mosquitoes as well as females of F1 generation of Ae. albopictus were significantly decreased. Conclusions The present study revealed the potential of the crude extract of C. aromaticus cultured cells in controlling vector mosquito populations in the effort to reduce the transmission of vector borne diseases. PMID:24075340

  3. Prevalence of Dental Caries in Kosovar Adult Population

    PubMed Central

    Begzati, Agim; Kelmendi, Jeta; Ilijazi, Donika; Kqiku, Lumnije

    2016-01-01

    Objectives. The aim of this study was to assess the prevalence of dental caries in the Kosovar adult population. Materials and Methods. A cross-sectional study in Kosovo was conducted examining 9387 patients, aged 18 upwards, between January 2010 and December 2011. Clinical evaluation was done using WHO criteria for evaluation of dental health status and data collection. Results. The prevalence of caries for the whole study was 72.80%. The mean DMFT index was 9.61 (±5.12) in the 18–34-year age group, 11.6 (±6.42) in the 35–44-year age group, 13.68 (±8.12) among the 45–64-year age group, 17.98 (±9.81) in the 65–74-year age group, and 23.19 (±9.41) in the age group of 75+ years, respectively. A significant difference of mean DMFT and its each component was observed between the ages (P < 0.001). Conclusion. This study comes out with the significant levels of dental caries among young Kosovar population (18–34 years old). PMID:27516774

  4. Evaluating the effects of mosquito control adulticides on honey bees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While mosquito control adulticides can be effective in rapidly reducing mosquito populations during times of high arbovirus transmission, the impacts of these control measures on pollinators has been of recent interest. The purpose of our study was to evaluate mosquito and honey bee mortality using ...

  5. The effect of temperature on life history traits of Culex mosquitoes.

    PubMed

    Ciota, Alexander T; Matacchiero, Amy C; Kilpatrick, A Marm; Kramer, Laura D

    2014-01-01

    Climatic changes forecasted in the coming years are likely to result in substantial alterations to the distributions and populations of vectors of arthropod-borne pathogens. Characterization of the effect of temperature shifts on the life history traits of specific vectors is needed to more accurately define how such changes could impact the epidemiological patterns of vector-borne disease. Here, we determined the effect of temperatures including 16, 20, 24, 28, and 32 degreeC on development time, immature survival, adult survival, mosquito size, blood feeding, and fecundity of both field and colonized populations of the Culex mosquitoes Culex pipiens L, Culex quinquefasciatus Say, and Culex restuans Theobald. Our results demonstrate that temperature significantly affects all of these traits, yet also that the extent of this effect is at times incongruent among temperatures, as well as being population and species-specific. Comparisons of colonized mosquitoes with field populations generally demonstrate decreased adult and immature survival, increased blood feeding and egg production, and significant variation in the effects of temperature, indicating that such colonies are not fully representative of natural populations. Results with field populations in general indicate that increases in temperature are likely to accelerate mosquito development, and that this effect is greater at temperatures below 24 degreeC, but also that temperature significantly increases mortality. Among field populations, Cx. restuans were most affected by temperature increases, with decreased longevity relative to other species and significant increases in adult and immature mortality measured with each incremental temperature increase. Despite the unique climates characteristic of the geographic ranges ofCx. quinquefasciatus and Cx. pipiens, evidence of significant species-specific adaptation to temperature ranges was not seen. Taken together, these results indicate that geographic region

  6. Species interactions among larval mosquitoes: context dependence across habitat gradients.

    PubMed

    Juliano, Steven A

    2009-01-01

    Biotic interactions involving mosquito larvae are context dependent, with effects of interactions on populations altered by ecological conditions. Relative impacts of competition and predation change across a gradient of habitat size and permanence. Asymmetrical competition is common and ecological context changes competitive advantage, potentially facilitating landscape-level coexistence of competitors. Predator effects on mosquito populations sometimes depend on habitat structure and on emergent effects of multiple predators, particularly interference among predators. Nonlethal effects of predators on mosquito oviposition, foraging, and life history are common, and their consequences for populations and for mosquito-borne disease are poorly understood. Context-dependent beneficial effects of detritus shredders on mosquitoes occur in container habitats, but these interactions appear to involve more than simple resource modification by shredders. Investigations of context-dependent interactions among mosquito larvae will yield greater understanding of mosquito population dynamics and provide useful model systems for testing theories of context dependence in communities.

  7. Species Interactions Among Larval Mosquitoes: Context Dependence Across Habitat Gradients

    PubMed Central

    Juliano, Steven A.

    2009-01-01

    Biotic interactions involving mosquito larvae are context dependent, with effects of interactions on populations altered by ecological conditions. Relative impacts of competition and predation change across a gradient of habitat size and permanence. Asymmetrical competition is common and ecological context changes competitive advantage, potentially facilitating landscape-level coexistence of competitors. Predator effects on mosquito populations sometimes depend on habitat structure and on emergent effects of multiple predators, particularly interference among predators. Nonlethal effects of predators on mosquito oviposition, foraging, and life history are common, and their consequences for populations and for mosquito-borne disease are poorly understood. Context-dependent beneficial effects of detritus shredders on mosquitoes occur in container habitats, but these interactions appear to involve more than simple resource modification by shredders. Investigations of context-dependent interactions among mosquito larvae will yield greater understanding of mosquito population dynamics and provide useful model systems for testing theories of context dependence in communities. PMID:19067629

  8. Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia

    PubMed Central

    Pérez-Castro, Rosalía; Castellanos, Jaime E; Olano, Víctor A; Matiz, María Inés; Jaramillo, Juan F; Vargas, Sandra L; Sarmiento, Diana M; Stenström, Thor Axel; Overgaard, Hans J

    2016-01-01

    The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models. PMID:27074252

  9. Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia.

    PubMed

    Pérez-Castro, Rosalía; Castellanos, Jaime E; Olano, Víctor A; Matiz, María Inés; Jaramillo, Juan F; Vargas, Sandra L; Sarmiento, Diana M; Stenström, Thor Axel; Overgaard, Hans J

    2016-04-01

    The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.

  10. Identification and genetic characterization of chikungunya virus from Aedes mosquito vector collected in the Lucknow district, North India.

    PubMed

    Nyari, N; Maan, H S; Sharma, S; Pandey, S N; Dhole, T N

    2016-06-01

    Chikungunya fever is an emerging mosquito-borne disease caused by the infection with chikungunya virus (CHIKV). The CHIKV has been rarely detected in mosquito vectors from Northern India, since vector surveillance is an effective strategy in controlling and preventing CHIKV transmission. Thus, virological investigation for CHIKV among mosquitoes of Aedes (A.) species was carried out in the Lucknow district during March 2010 to October 2011. We collected adult mosquitoes from areas with CHIKV positive patients. The adult Aedes mosquito samples were pooled, homogenized, clarified and tested for CHIKV by nonstructural protein 1 (nsP1) gene based polymerase chain reaction (PCR). A total 91 mosquito pools comprising of adult A. aegypti and A. albopictus were tested for CHIKV. The partial envelope protein (E1) gene sequences of mosquito-borne CHIKV strains were analyzed for genotyping. Of 91 pools, 6 pools of A. aegypti; and 2 pools of A. albopictus mosquitoes were identified positive for CHIKV by PCR. The phylogenetic analysis revealed clustering of CHIKV strains in two sub-lineages within the monophyletic East-Central South African (ECSA) genotype. Novel amino acid changes at the positions 294 (P294L) and 295 (S295F) were observed during analysis of amino acid sequence of the partial E1 gene. This study demonstrates the genetic diversity of circulating CHIKV strains and reports the first detection of CHIKV strains in Aedes vector species from the state of Uttar Pradesh. These findings have implication for vector control strategies to mitigate vector population to prevent the likelihood of CHIKV epidemic in the near future.

  11. Airway responsiveness to sulfur dioxide in an adult population sample.

    PubMed

    Nowak, D; Jörres, R; Berger, J; Claussen, M; Magnussen, H

    1997-10-01

    We determined the prevalence of airway hyperresponsiveness to sulfur dioxide (SO2) in an adult population sample of 790 subjects 20 to 44 yr of age. Subjects were drawn randomly from the population of Hamburg, Northern Germany, within the framework of the European Community Respiratory Health Survey. In addition, we analyzed the relationship between SO2 responsiveness and a number of risk factors, such as a history of respiratory symptoms, methacholine responsiveness, and atopy derived from skin-prick test results. SO2 inhalation challenges were performed during isocapnic hyperventilation at constant rate (40 L x min(-1), for 3 min) with doubling concentrations of SO2 up to a maximum concentration of 2.0 ppm. If subjects achieved a 20% decrease in FEV1 from baseline during the challenge, they were considered to be hyperresponsive to SO2. The raw prevalence of SO2 hyperresponsiveness within the population sample studied was 3.4% (95% confidence interval [CI]: 2.3 to 5.0%). Adjustment for nonparticipation led to an estimated prevalence of SO2 hyperresponsiveness of 5.4%. Among subjects with hyperresponsiveness to methacholine, 22.4% (95% CI: 20.1 to 25.3) demonstrated hyperresponsiveness to SO2. There was no significant correlation between the degrees of hyperresponsiveness to methacholine and SO2. Predictors of a positive SO2 response were hyperresponsiveness to methacholine (p < 0.0001), a positive history of respiratory symptoms (p < 0.05), and a positive skin-prick test to at least one common allergen (p < 0.05). We conclude from these data that airway hyperresponsiveness to SO2 can be found in about 20 to 25% of subjects within the 20- to 44-yr age range who are hyperresponsive to methacholine.

  12. The Influence of Diet on the Use of Near-Infrared Spectroscopy to Determine the Age of Female Aedes aegypti Mosquitoes.

    PubMed

    Liebman, Kelly; Swamidoss, Isabel; Vizcaino, Lucrecia; Lenhart, Audrey; Dowell, Floyd; Wirtz, Robert

    2015-05-01

    Interventions targeting adult mosquitoes are used to combat transmission of vector-borne diseases, including dengue. Without available vaccines, targeting the primary vector, Aedes aegypti, is essential to prevent transmission. Older mosquitoes (≥ 7 days) are of greatest epidemiological significance due to the 7-day extrinsic incubation period of the virus. Age-grading of female mosquitoes is necessary to identify post-intervention changes in mosquito population age structure. We developed models using near-infrared spectroscopy (NIRS) to age-grade adult female Ae. aegypti. To determine if diet affects the ability of NIRS models to predict age, two identical larval groups were fed either fish food or infant cereal. Adult females were separated and fed sugar water ± blood, resulting in four experimental groups. Females were killed 1, 4, 7, 10, 13, or 16 days postemergence. The head/thorax of each mosquito was scanned using a near-infrared spectrometer. Scans from each group were analyzed, and multiple models were developed using partial least squares regression. The best model included all experimental groups, and positively predicted the age group (< or ≥ 7 days) of 90.2% mosquitoes. These results suggest both larval and adult diets can affect the ability of NIRS models to accurately assign age categories to female Ae. aegypti.

  13. Predatory efficiency of the water bug Sphaerodema annulatum on mosquito larvae (Culex quinquefasciatus) and its effect on the adult emergence.

    PubMed

    Aditya, G; Bhattacharyya, S; Kundu, N; Saha, G K; Raut, S K

    2004-11-01

    The daily number of IV instar larva of Culex quinquefasciatus killed, rate of pupation and adult emergence was noted in presence of the predatory water bug Sphaerodema annulatum for a period of seven consecutive days, experimentally, in the laboratory. The rate of IV instar larva killed by the water bugs on an average was 65.17 per day. The rate of pupation ranged between 7.6 and 48 in control while in presence of water bugs it ranged between 6 and 35. The rate of adult emergence in control experiments varied between 1.4 and 4.8 per day, which was reduced to only 0.4-28.8 per day in case of the water bugs. The results clearly indicate that the water bugs on its way of predation reduces the rate of pupation and adult emergence of Cx. quinquefasciatus significantly which calls for an extensive field trials.

  14. On the analysis of effectiveness in mass application of mosquito repellent for dengue disease prevention

    NASA Astrophysics Data System (ADS)

    Aldila, D.; Soewono, E.; Nuraini, N.

    2012-05-01

    Dengue disease has been known as one of dangerous vector-borne diseases and become serious threat in many tropical countries. With no vaccine and antiviral available until nowadays, and frequent appearance of extraordinary dengue outbreaks, many governments are forced to declare national problem for dengue. At this moment, the only method available to prevent dengue disease transmission is to combat the disease-carrying mosquitoes as well as to reduce the contact between human and mosquitoes. The fast growing dengue transmission in many countries in recent years indicates that the mosquito control programs are far from successful. The use of mosquito repellent is one possible instrument which could be used as an effective mass treatment to prevent the dengue outbreak during endemic period. Here in this paper a Susceptible-Infectious-Recovered (S-I-R) dengue transmission model with repellent mass treatment is being applied to portions of children and adult compartments. Analysis of the basic reproductive ratio (Ro) of the model is done. It is shown, with reasonable choices of portions of treated children and adults, in combination with reduction of mosquito population, the basic reproductive ratio can be significantly reduced and occurrence of endemic can be avoided. Numerical simulations are shown for various treatment scenarios.

  15. Spatial and temporal characterization of mosquito distribution and arbovirus transmission activity in St. Johns County, Florida. St. Augustine, FL.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Global information technology (GIT) (including Global Positioning System [GPS], Geographic Information Systems [GIS], and image analysis) can be used to develop adult mosquito sampling methods and to characterize adult mosquito distributions and disease transmission patterns. At this meeting of v...

  16. Socioeconomic status affects mosquito (Diptera: Culicidae) larval habitat type availability and infestation level.

    PubMed

    Dowling, Zara; Ladeau, Shannon L; Armbruster, Peter; Biehler, Dawn; Leisnham, Paul T

    2013-07-01

    Mosquito populations are largely regulated by processes occurring at the larval stage. We sampled mosquito larval microhabitats (mostly water-holding containers) in six neighborhoods in the Washington, DC, area that varied in socioeconomic status (SES) and housing structure (row houses vs. stand-alone houses) to test associations among these neighborhood characteristics, microhabitat abundance and parameters, and mosquito occurrence and densities. Thirty-four percent (33.9%) of sampled microhabitats contained mosquito larvae, and 93.1% of larvae were Aedes albopictus Skuse or Culex pipiens L. Five specific container types (drains, corrugated flexible drainpipes, planters, garbage cans, and buckets) accounted for the majority of water-holding (56.0%) and mosquito-positive (50.6%) microhabitats sampled. We found no associations between SES or housing structure with total microhabitat abundance per yard, mosquito occurrence or mosquito densities per microhabitat. In contrast, container purpose varied with SES, with low SES neighborhoods having greater numbers of disused containers and lower numbers of functional containers than low and medium SES neighborhoods. Ae. albopictus were 83% more abundant in disused containers, whereas Cx. pipiens were more abundant in structural and functional containers, possibly owing to species-specific oviposition and development related to water quality. Ae. albopictus densities increased over the summer, whereas Cx. pipiens densities remained constant. Ae. albopictus is usually the dominant pest in urban areas in the eastern United States; therefore, integrated mosquito management programs should incorporate the elimination of disused containers to reduce its infestation and adult production, especially in low SES neighborhoods where they occur most frequently.

  17. RELATIVE ABUNDANCE AND SPECIES COMPOSITION OF MOSQUITO POPULATIONS (DIPTERA:CULICIDAE) IN A LA CROSSE VIRUS- ENDEMIC AREA IN WESTERN NORTH CAROLINA

    EPA Science Inventory

    Container surveys were conducted in 5 communities on the Cherokee Indian Reservation, an area of western North Carolina endemic for transmission of La Crosse (LAC) virus, to determine the potential for peridomestic mosquito breeding, the relative abundance of mosquito species, an...

  18. Population Pharmacokinetics of Benznidazole in Adult Patients with Chagas Disease

    PubMed Central

    Aldasoro, E.; Guerrero, L.; Posada, E.; Serret, N.; Mejía, T.; Urbina, J. A.; Gascón, J.

    2015-01-01

    The aim of the present study was to build a population pharmacokinetic (popPK) model to characterize benznidazole (BNZ) pharmacokinetics in adults with chronic Chagas disease. This study was a prospective, open-label, single-center clinical trial approved by the local ethics committee. Patients received BNZ at 2.5 mg/kg of body weight/12 h (Abarax, Elea Laboratory, Argentina) for 60 days. Plasma BNZ samples were taken several times during the study and analyzed by high-performance liquid chromatography with UV-visible detection (HPLC-UV). The popPK analysis was done with NONMEMv.7.3. Demographic and biological data were tested as covariates. Intraindividual, interoccasion, and residual variabilities were modeled. Internal and external validations were completed to assess the robustness of the model. Later on, simulations were performed to generate BNZ concentration-time course profiles for different dosage regimens. A total of 358 plasma BNZ concentrations from 39 patients were included in the analysis. A one-compartment PK model characterized by clearance (CL/F) and the apparent volume of distribution (V/F), with first-order absorption (Ka) and elimination, adequately described the data (CL/F, 1.73 liters/h; V/F, 89.6 liters; and Ka, 1.15 h−1). No covariates were found to be significant for CL/F and V/F. Internal and external validations of the final model showed adequate results. Data from simulations revealed that a dose of 2.5 mg/kg/12 h might lead to overexposure in most patients. A lower dose (2.5 mg/kg/24 h) was able to achieve trough BNZ plasma concentrations within the accepted therapeutic range of 3 to 6 mg/liter. In summary, we developed a population PK model for BNZ in adults with chronic Chagas disease. Dosing simulations showed that a BNZ dose of 2.5 mg/kg/24 h will adequately keep BNZ trough plasma concentrations within the recommended target range for the majority of patients. (This study has been registered at EudraCT under number 2011

  19. Dengue in Java, Indonesia: Relevance of Mosquito Indices as Risk Predictors

    PubMed Central

    Wijayanti, Siwi P. M.; Sunaryo, Sunaryo; Suprihatin, Suprihatin; McFarlane, Melanie; Rainey, Stephanie M.; Dietrich, Isabelle; Schnettler, Esther; Biek, Roman; Kohl, Alain

    2016-01-01

    Background No vaccine is currently available for dengue virus (DENV), therefore control programmes usually focus on managing mosquito vector populations. Entomological surveys provide the most common means of characterising vector populations and predicting the risk of local dengue virus transmission. Despite Indonesia being a country strongly affected by DENV, only limited information is available on the local factors affecting DENV transmission and the suitability of available survey methods for assessing risk. Methodology/principal findings We conducted entomological surveys in the Banyumas Regency (Central Java) where dengue cases occur on an annual basis. Four villages were sampled during the dry and rainy seasons: two villages where dengue was endemic, one where dengue cases occurred sporadically and one which was dengue-free. In addition to data for conventional larvae indices, we collected data on pupae indices, and collected adult mosquitoes for species identification in order to determine mosquito species composition and population density. Traditionally used larval indices (House indices, Container indices and Breteau indices) were found to be inadequate as indicators for DENV transmission risk. In contrast, species composition of adult mosquitoes revealed that competent vector species were dominant in dengue endemic and sporadic villages. Conclusions/significance Our data suggested that the utility of traditional larvae indices, which continue to be used in many dengue endemic countries, should be re-evaluated locally. The results highlight the need for validation of risk indicators and control strategies across DENV affected areas here and perhaps elsewhere in SE Asia. PMID:26967524

  20. Population Dynamics of Blood-Fed Female Mosquitoes and Comparative Efficacy of Resting Boxes in Collecting them from the Northwestern Part of Riverside County, California

    PubMed Central

    Sandhu, Tejbir S; Williams, Gregory W; Haynes, Bryan W; Dhillon, Major S

    2013-01-01

    Objectives: Testing of blood-fed mosquitoes plays an integral role in arbovirus surveillance and in understanding its interaction mechanisms between host, vector and reservoir. The present study was undertaken to evaluate the efficacy of two different traps (gravid and resting boxes) for collection of blood-fed mosquitoes in the northwestern part of Riverside County. Materials and Methods: Three trapping sites were selected in the Northwest Mosquito and Vector Control District of Riverside County, California. At each site resting boxes and gravid traps were set; and mosquitoes were collected on a weekly basis between July-December 2009. Mosquitoes were transported over blue ice, identified up to species level on chill table, and classified as male, female and blood-fed females. Results: During this study period, 3953 mosquitoes (826 blood-fed females) belonging to three different genera and eight species were collected; resting boxes collecting maximum number (seven) of mosquito species. Overall as well as individually in each trap kind, the most abundant mosquito species collected was Cx. quinquefasciatus. The proportion of blood-fed females of the Culex species collected in resting boxes was 28.8 times more, while of blood-fed females of Cx. quinquefasciatus was 32.2 times more than the proportion collected from gravid traps. Conclusions: Overall, the proportion of blood-fed female mosquitoes collected for each species trapped was highest in resting boxes. Additionally, resting boxes showed the advantage of extremely low running and maintenance cost; generation of no hazardous waste; quick turnaround time in terms of mosquito collection per man-hour spent; and they were less prone to vandalism or thefts. PMID:23599612

  1. Multiple Cytochrome P450 genes: their constitutive overexpression and permethrin induction in insecticide resistant mosquitoes, Culex quinquefasciatus.

    PubMed

    Liu, Nannan; Li, Ting; Reid, William R; Yang, Ting; Zhang, Lee

    2011-01-01

    Four cytochrome P450 cDNAs, CYP6AA7, CYP9J40, CYP9J34, and CYP9M10, were isolated from mosquitoes, Culex quinquefasciatus. The P450 gene expression and induction by permethrin were compared for three different mosquito populations bearing different resistance phenotypes, ranging from susceptible (S-Lab), through intermediate (HAmCq(G0), the field parental population) to highly resistant (HAmCq(G8), the 8(th) generation of permethrin selected offspring of HAmCq(G0)). A strong correlation was found for P450 gene expression with the levels of resistance and following permethrin selection at the larval stage of mosquitoes, with the highest expression levels identified in HAmCq(G8), suggesting the importance of CYP6AA7, CYP9J40, CYP9J34, and CYP9M10 in the permethrin resistance of larva mosquitoes. Only CYP6AA7 showed a significant overexpression in HAmCq(G8) adult mosquitoes. Other P450 genes had similar expression levels among the mosquito populations tested, suggesting different P450 genes may be involved in the response to insecticide pressure in different developmental stages. The expression of CYP6AA7, CYP9J34, and CYP9M10 was further induced by permethrin in resistant mosquitoes. Taken together, these results indicate that multiple P450 genes are up-regulated in insecticide resistant mosquitoes through both constitutive overexpression and induction mechanisms, thus increasing the overall expression levels of P450 genes.

  2. Aestivation of the African Malaria Mosquito, Anopheles gambiae in the Sahel

    PubMed Central

    Lehmann, Tovi; Dao, Adama; Yaro, Alpha Seydou; Adamou, Abdoulaye; Kassogue, Yaya; Diallo, Moussa; Sékou, Traoré; Coscaron-Arias, Cecilia

    2010-01-01

    The African malaria mosquito, Anopheles gambiae, inhabits diverse environments including dry savannas, where surface waters required for larval development are absent for 4–8 months per year. Under such conditions, An. gambiae virtually disappears. Whether populations survive the long dry season by aestivation (a dormant state promoting extended longevity during the summer) or are reestablished by migrants from distant locations where larval sites persist has remained an enigma for over 60 years. Resolving this question is important, because fragile dry season populations may be more susceptible to control. Here, we show unequivocally that An. gambiae aestivates based on a demographic study and a mark release–recapture experiment spanning the period from the end of one wet season to the beginning of the next. During the dry season, An. gambiae was barely detectable in Sahelian villages of Mali. Five days after the first rain, before a new generation of adults could be produced, mosquito abundance surged 10-fold, implying that most mosquitoes were concealed locally until the rain. Four days after the first rain, a marked female An. gambiae s.s. was recaptured. Initially captured, marked, and released at the end of the previous wet season, she has survived the 7-month-long dry season. These results provide evidence that An. gambiae persists throughout the dry season by aestivation and open new questions for mosquito and parasite research. Improved malaria control by targeting aestivating mosquitoes using existing or novel strategies may be possible. PMID:20810827

  3. Respiratory pattern in an adult population of dystrophic patients.

    PubMed

    D'Angelo, M G; Romei, M; Lo Mauro, A; Marchi, E; Gandossini, S; Bonato, S; Comi, G P; Magri, F; Turconi, A C; Pedotti, A; Bresolin, N; Aliverti, A

    2011-07-15

    We studied respiratory function and Chest Wall kinematics in a large population of adult patients affected by slow course muscular dystrophies such as Limb-Girdle Muscular Dystrophy (LGMD, n=38), Becker Muscular Dystrophy (BMD, n=20) and Facio-Scapulo Humeral Dystrophy (FSHD, n=30), through standard spirometry and through the Optoelectronic Plethysmography, to measure the thoraco-abdominal motion during Quiet Breathing and Slow Vital Capacity maneuvers. Within the restrictive pulmonary syndrome characterizing LGMD and FSHD, several different thoraco-abdominal patterns compared to those of healthy subjects were present in the more advanced stages of the disease. These differences were present in the seated position, during the execution of a maximal maneuver such as Slow Vital Capacity. A global respiratory (both inspiratory and expiratory) muscle involvement was more pronounced in the LGMD and FSHD than in the BMD patients, and a significant reduction of abdominal contribution in wheelchair bound patients was observed. In conclusion, OEP technique is able to reveal mild initial modifications in the respiratory muscles in FSHD and LGMD patients, which could be helpful for functional and new therapeutic strategy evaluation.

  4. Perceived stress and mortality in a Taiwanese older adult population.

    PubMed

    Vasunilashorn, Sarinnapha; Glei, Dana A; Weinstein, Maxine; Goldman, Noreen

    2013-11-01

    Perceived stress is associated with poor health outcomes including negative affect, increased susceptibility to the common cold and cardiovascular disease; the consequences of perceived stress for mortality, however, have received less attention. This study characterizes the relationship between perceived stress and 11-year mortality in a population of Taiwanese adults aged 53+ years. Using the Survey of Health and Living Status of the Near Elderly and Elderly of Taiwan, we calculated a composite measure of perceived stress based on six items pertaining to the health, financial situation, and occupation of the respondents and their families. Proportional hazard models were used to determine whether perceived stress predicted mortality. After adjusting for sociodemographic factors only, we found that a one standard deviation increase in perceived stress was associated with a 19% increase in all-cause mortality risk during the 11-year follow-up period (hazard ratio, HR = 1.19, 95% confidence interval, CI 1.13-1.26). The relationship was greatly attenuated when perceptions of stress regarding health were excluded, and was not significant after adjusting for medical conditions, mobility limitations and depressive symptoms. We conclude that the association between perceived stress and mortality is explained by an individual's current health; however, our data do not allow us to distinguish between two possible interpretations of this conclusion: (a) the relationship between perceived stress and mortality is spurious, or (b) poor health acts as the mediator.

  5. Levels of Engagement and Barriers to Physical Activity in a Population of Adults with Learning Disabilities

    ERIC Educational Resources Information Center

    Hawkins, Andrew; Look, Roger

    2006-01-01

    This study examined levels of, and barriers to, physical activity in a population of 19 adults with learning disabilities living in community supported accommodation, using diary records and semi-structured interviews with staff. The levels of physical activity were higher in the sample population than previous figures for adults with learning…

  6. Crisis Model for Older Adults: Special Considerations for an Aging Population

    ERIC Educational Resources Information Center

    Jungers, Christin M.; Slagel, Leslie

    2009-01-01

    As the U.S. population ages, counselors must begin structuring their interactions to meet the unique needs of older adults, especially in the area of crisis intervention. The purposes of this article are to draw attention to the rapidly growing, often disregarded older population and to introduce the Crisis Model for Older Adults (CM-OA), an…

  7. Mosquito and Blackfly Category Manual.

    ERIC Educational Resources Information Center

    Bowman, James S.; And Others

    This manual provides information needed to meet the standards for pesticide applicator certification. Section one is concerned with the morphology, life cycle and breeding areas of mosquitoes and the diseases resulting from their presence. The second section covers similar categories in relation to the black fly population. Calculation methods and…

  8. Mosquito-Disseminated Insecticide for Citywide Vector Control and Its Potential to Block Arbovirus Epidemics: Entomological Observations and Modeling Results from Amazonian Brazil

    PubMed Central

    Abad-Franch, Fernando; Luz, Sérgio L. B.

    2017-01-01

    Background Mosquito-borne viruses threaten public health worldwide. When the ratio of competent vectors to susceptible humans is low enough, the virus’s basic reproductive number (R0) falls below 1.0 (each case generating, on average, <1.0 additional case) and the infection fades out from the population. Conventional mosquito control tactics, however, seldom yield R0 < 1.0. A promising alternative uses mosquitoes to disseminate a potent growth-regulator larvicide, pyriproxyfen (PPF), to aquatic larval habitats; this kills most mosquito juveniles and substantially reduces adult mosquito emergence. We tested mosquito-disseminated PPF in Manacapuru, a 60,000-inhabitant city (~650 ha) in Amazonian Brazil. Methods and Findings We sampled juvenile mosquitoes monthly in 100 dwellings over four periods in February 2014–January 2016: 12 baseline months, 5 mo of citywide PPF dissemination, 3 mo of focal PPF dissemination around Aedes-infested dwellings, and 3 mo after dissemination ended. We caught 19,434 juvenile mosquitoes (66% Aedes albopictus, 28% Ae. aegypti) in 8,271 trap-months. Using generalized linear mixed models, we estimated intervention effects on juvenile catch and adult emergence while adjusting for dwelling-level clustering, unequal sampling effort, and weather-related confounders. Following PPF dissemination, Aedes juvenile catch decreased by 79%–92% and juvenile mortality increased from 2%–7% to 80%–90%. Mean adult Aedes emergence fell from 1,077 per month (range 653–1,635) at baseline to 50.4 per month during PPF dissemination (range 2–117). Female Aedes emergence dropped by 96%–98%, such that the number of females emerging per person decreased to 0.06 females per person-month (range 0.002–0.129). Deterministic models predict, under plausible biological-epidemiological scenarios, that the R0 of typical Aedes-borne viruses would fall from 3–45 at baseline to 0.004–0.06 during PPF dissemination. The main limitations of our study were

  9. Mosquito Traps: An Innovative, Environmentally Friendly Technique to Control Mosquitoes

    PubMed Central

    Poulin, Brigitte; Lefebvre, Gaëtan; Muranyi-Kovacs, Camille; Hilaire, Samuel

    2017-01-01

    We tested the use of mosquito traps as an alternative to spraying insecticide in Camargue (France) following the significant impacts observed on the non-target fauna through Bti persistence and trophic perturbations. In a village of 600 inhabitants, 16 Techno Bam traps emitting CO2 and using octenol lures were set from April to November 2016. Trap performance was estimated at 70% overall based on mosquitoes landing on human bait in areas with and without traps. The reduction of Ochlerotatus caspius and Oc. detritus, the two species targeted by Bti spraying, was, respectively, 74% and 98%. Traps were less efficient against Anopheles hyrcanus (46%), which was more attracted by lactic acid than octenol lures based on previous tests. Nearly 300,000 mosquitoes from nine species were captured, with large variations among traps, emphasizing that trap performance is also influenced by surrounding factors. Environmental impact, based on the proportion of non-target insects captured, was mostly limited to small chironomids attracted by street lights. The breeding success of a house martin colony was not significantly affected by trap use, in contrast to Bti spraying. Our experiment confirms that the deployment of mosquito traps can offer a cost-effective alternative to Bti spraying for protecting local populations from mosquito nuisance in sensitive natural areas. PMID:28335456

  10. Mosquito Consumption by Insectivorous Bats: Does Size Matter?

    PubMed Central

    Gonsalves, Leroy; Bicknell, Brian; Law, Brad; Webb, Cameron; Monamy, Vaughan

    2013-01-01

    Insectivorous bats have often been touted as biological control for mosquito populations. However, mosquitoes generally represent only a small proportion of bat diet. Given the small size of mosquitoes, restrictions imposed on prey detectability by low frequency echolocation, and variable field metabolic rates (FMR), mosquitoes may not be available to or profitable for all bats. This study investigated whether consumption of mosquitoes was influenced by bat size, which is negatively correlated with echolocation frequency but positively correlated with bat FMR. To assess this, we investigated diets of five eastern Australian bat species (Vespadelus vulturnus Thomas, V. pumilus Gray, Miniopterus australis Tomes, Nyctophilus gouldi Tomes and Chalinolobus gouldii Gray) ranging in size from 4-14 g in coastal forest, using molecular analysis of fecal DNA. Abundances of potential mosquito and non-mosquito prey were concurrently measured to provide data on relative prey abundance. Aedes vigilax was locally the most abundant mosquito species, while Lepidoptera the most abundant insect order. A diverse range of prey was detected in bat feces, although members of Lepidoptera dominated, reflecting relative abundance at trap sites. Consumption of mosquitoes was restricted to V. vulturnus and V. pumilus, two smaller sized bats (4 and 4.5 g). Although mosquitoes were not commonly detected in feces of V. pumilus, they were present in feces of 55 % of V. vulturnus individuals. To meet nightly FMR requirements, Vespadelus spp. would need to consume ~600-660 mosquitoes on a mosquito-only diet, or ~160-180 similar sized moths on a moth-only diet. Lower relative profitability of mosquitoes may provide an explanation for the low level of mosquito consumption among these bats and the absence of mosquitoes in feces of larger bats. Smaller sized bats, especially V. vulturnus, are likely to be those most sensitive to reductions in mosquito abundance and should be monitored during mosquito

  11. DsRed2 transient expression in Culex quinquefasciatus mosquitoes.

    PubMed

    Wilke, André Barretto Bruno; Scaife, Sarah; Alphey, Luke; Marrelli, Mauro Toledo

    2013-06-01

    Culex quinquefasciatus mosquitoes have been successfully genetically modified only once, despite the efforts of several laboratories to transform and establish a stable strain. We have developed a transient gene expression method, in Culex, that delivers plasmid DNA directly to the mosquito haemolymph and additional tissues. We were able to express DsRed2 fluorescent protein in adult Cx. quinquefasciatus mosquitoes by injecting plasmids directly into their thorax. The expression of DsRed2 in adult Cx. quinquefasciatus mosquitoes is an important stepping stone to genetic transformation and the potential use of new control strategies and genetic interactions.

  12. Correlation of Osteoporosis and Calcium Urolithiasis in Adult Population

    PubMed Central

    Bijelic, Radojka; Milicevic, Snjezana; Balaban, Jagoda

    2016-01-01

    , the share of those who do not have normal findings is higher in the elderly population. Conclusion: Our study has just shown that in adult patients with calcium urolithiasis osteoporosis is more prevalent in older patients and more pronounced in patients with calcium urolithiasis in relation to the population without the same. PMID:26980936

  13. Estimate of intake of sulfites in the Belgian adult population.

    PubMed

    Vandevijvere, S; Temme, E; Andjelkovic, M; De Wil, M; Vinkx, C; Goeyens, L; Van Loco, J

    2010-08-01

    An exposure assessment was performed to estimate the usual daily intake of sulfites in the Belgian adult population. Food consumption data were retrieved from the national food consumption survey. In a first step, individual food consumption data were multiplied with the maximum permitted use levels for sulfites, expressed as sulphur dioxide, per food group (Tier 2). In a second step, on the basis of a literature review of the occurrence of sulfites in different foods, the results of the Tier 2 exposure assessment and available occurrence data from the control programme of the competent authority, a refined list of foods was drafted for the quantification of sulphite. Quantification of sulphite was performed by a high-performance ion chromatography method with eluent conductivity detector in beers and potato products. Individual food consumption data were then multiplied with the actual average concentrations of sulfite per food group, or the maximum permitted levels in case actual levels were not available (partial Tier 3). Usual intakes were calculated using the Nusser method. The mean intake of sulfites was 0.34 mg kg(-1) bw day(-1) (Tier 2), corresponding to 49% of the acceptable daily intake (ADI) and 0.19 mg kg(-1) bw day(-1), corresponding to 27% of the ADI (partial Tier 3). The food group contributing most to the intake of sulfites was wines. The results showed that the intake of sulfites is likely to be below the ADI in Belgium. However, there are indications that high consumers of wine have an intake around the ADI.

  14. Population structure among octocoral adults and recruits identifies scale dependent patterns of population isolation in The Bahamas

    PubMed Central

    Porto-Hannes, Isabel

    2015-01-01

    Patterns of dispersal and connectivity of the Caribbean gorgonian Antillogorgia elisabethae in The Bahamas were assessed in both adults and recently settled recruits from 13 sites using microsatellite loci. Adult populations along the Little Bahama Bank (LBB) exhibited a clear pattern of isolation by distance (IBD) which described 86% of the variance in pairwise genetic distances. Estimates of dispersal based on the IBD model suggested dispersal distances along the LBB on the order of 100 m. Increasing the spatial scale to include sites separated by open ocean generated an apparent IBD signal but the relationship had a greater slope and explained less of the variance. This relationship with distance reflected both stepping stone based IBD and regional differentiation probably created by ocean currents and barriers to dispersal that are correlated with geographic distance. Analysis of recruits from 4 sites on the LBB from up to 6 years did not detect differences between years nor differences with adult populations. The result suggests that neither selection on recruits nor inter-annual variation in dispersal affected adult population structure. Assignment tests of recruits indicated the most likely sources of the recruits were the local or adjacent populations. Most of the patterning in population structure in the northern Bahamas can be explained by geographic distance and oceanographic connectivity. Recognition of these complex patterns is important in developing management plans for A. elisabethae and in understanding the effects of disturbance to adult populations of A. elisabethae and similar species with limited dispersal. PMID:26157606

  15. Insecticidal activity of isobutylamides derived from Piper nigrum against adult of two mosquito species, Culex pipiens pallens and Aedes aegypti.

    PubMed

    Park, Il-Kwon

    2012-01-01

    The insecticidal activity of Piper nigrum fruit-derived piperidine alkaloid (piperine) and N-isobutylamide alkaloids (pellitorine, guineensine, pipercide and retrofractamide A) against female adults of Culex pipiens pallens and Aedes aegypti was examined. On the basis of 24-h LD(50) values, the compound most toxic to female C. pipiens pallens was pellitorine (0.4 µg/♀) followed by guineensine (1.9 µg/♀), retrofractamide A (2.4 µg/♀) and pipercide (3.2 µg/♀). LD(50) value of chlorpyrifos was 0.03 µg/♀. Against female A. aegypti, the insecticidal activity was more pronounced in pellitorine (0.17 µg/♀) than in retrofractamide A (1.5 µg/♀), guineensine (1.7 µg/♀), and pipercide (2.0 µg/♀). LD(50) value of chlorpyrifos was 0.0014 µg/♀.

  16. Wolbachia and cytoplasmic incompatibility in the California Culex pipiens mosquito species complex: parameter estimates and infection dynamics in natural populations.

    PubMed Central

    Rasgon, Jason L; Scott, Thomas W

    2003-01-01

    Before maternally inherited bacterial symbionts like Wolbachia, which cause cytoplasmic incompatibility (CI; reduced hatch rate) when infected males mate with uninfected females, can be used in a program to control vector-borne diseases it is essential to understand their dynamics of infection in natural arthropod vector populations. Our study had four goals: (1) quantify the number of Wolbachia strains circulating in the California Culex pipiens species complex, (2) investigate Wolbachia infection frequencies and distribution in natural California populations, (3) estimate the parameters that govern Wolbachia spread among Cx. pipiens under laboratory and field conditions, and (4) use these values to estimate equilibrium levels and compare predicted infection prevalence levels to those observed in nature. Strain-specific PCR, wsp gene sequencing, and crossing experiments indicated that a single Wolbachia strain infects Californian Cx. pipiens. Infection frequency was near or at fixation in all populations sampled for 2 years along a >1000-km north-south transect. The combined statewide infection frequency was 99.4%. Incompatible crosses were 100% sterile under laboratory and field conditions. Sterility decreased negligibly with male age in the laboratory. Infection had no significant effect on female fecundity under laboratory or field conditions. Vertical transmission was >99% in the laboratory and approximately 98.6% in the field. Using field data, models predicted that Wolbachia will spread to fixation if infection exceeds an unstable equilibrium point above 1.4%. Our estimates accurately predicted infection frequencies in natural populations. If certain technical hurdles can be overcome, our data indicate that Wolbachia can invade vector populations as part of an applied transgenic strategy for vector-borne disease reduction. PMID:14704183

  17. History of Aedes mosquitoes in Hawaii.

    PubMed

    Winchester, Jonathan C; Kapan, Durrell D

    2013-06-01

    As a geographically isolated island chain with no native mosquitoes, Hawaii is a model for examining the mechanisms behind insect vector invasions and their subsequent interactions with each other and with human populations. The yellow fever mosquito, Aedes aegypti, and the Asian tiger mosquito, Ae. albopictus, have been responsible for epidemics of dengue in Hawaii. As one of the world's earliest locations to be invaded by both species, Hawaii's history is particularly relevant because both species are currently invading new areas worldwide and are implicated in outbreaks of emergent or reemergent pathogens such as dengue, chikungunya, and yellow fever. Here we analyze the historical records of mosquito introductions in order to understand the factors that have led to the current distribution of these 2 mosquitoes in the Hawaiian Islands.

  18. Mosquito Surveillance Revealed Lagged Effects of Mosquito Abundance on Mosquito-Borne Disease Transmission: A Retrospective Study in Zhejiang, China

    PubMed Central

    Guo, Song; Ling, Feng; Hou, Juan; Wang, Jinna; Fu, Guiming; Gong, Zhenyu

    2014-01-01

    Mosquito-borne diseases (MBDs) are still threats to public health in Zhejiang. In this study, the associations between the time-lagged mosquito capture data and MBDs incidence over five years were used to examine the potential effects of mosquito abundance on patterns of MBDs epidemiology in Zhejiang during 2008–2012. Light traps were used to collect adult mosquitoes at 11 cities. Correlation tests with and without time lag were performed to investigate the correlations between MBDs incidence rates and mosquito abundance by month. Selected MBDs consisted of Japanese encephalitis (JE), dengue fever (DF) and malaria. A Poisson regression analysis was performed by using a generalized estimating equations (GEE) approach, and the most parsimonious model was selected based on the quasi-likelihood based information criterion (QICu). We identified five mosquito species and the constituent ratio of Culex pipiens pallens, Culex tritaeniorhynchus, Aedes albopictus, Anopheles sinensis and Armigeres subalbatus was 66.73%, 21.47%, 6.72%, 2.83% and 2.25%, respectively. The correlation analysis without and with time lag showed that Culex mosquito abundance at a lag of 0 or 1 month was positively correlated with JE incidence during 2008–2012, Ae. albopictus abundance at a lag of 1 month was positively correlated with DF incidence in 2009, and An. sinensis abundance at a lag of 0–2 months was positively correlated with malaria incidence during 2008–2010. The Poisson regression analysis showed each 0.1 rise of monthly mosquito abundance corresponded to a positive increase of MBD cases for the period of 2008–2012. The rise of mosquito abundance with a lag of 0–2 months increased the risk of human MBDs infection in Zhejiang. Our study provides evidence that mosquito monitoring could be a useful early warning tool for the occurrence and transmission of MBDs. PMID:25393834

  19. Demographic Demise: The Declining Young Adult Population in New England

    ERIC Educational Resources Information Center

    Gittell, Ross

    2007-01-01

    Young adult workers provide businesses with the dynamic labor force and fresh ideas they need to innovate and grow. With their contributions to cultural, intellectual and social life, young adults also make New England a vibrant and interesting place to live. Young families support local schools and demand a strong educational system. Yet New…

  20. Satellite Vegetation Index Data as a Tool to Forecast Population Dynamics of Medically Important Mosquitoes at Military Installations in the Continental United States

    DTIC Science & Technology

    2008-07-01

    samples vary with the outcomes of the bionomic properties of the mosquito species themselves, such as flight range, quality and avail- ability of...Surveillance Data Mosquito Species Aedes atbopictux Aedes ve.xans Anopheles crucians CoquiHemdiii perturbans Culi seta melanura Cule.x erythrothorax Culex...ponds Heavily vegetated bodies of water Tree holes and swamp.s Cattail marshes and ponds Stagnant water pools Fresh or foul water pools Salt marshes Tree

  1. Factors and Mechanisms for Pharmacokinetic Differences between Pediatric Population and Adults

    PubMed Central

    Fernandez, Eva; Perez, Raul; Hernandez, Alfredo; Tejada, Pilar; Arteta, Marta; Ramos, Jose T.

    2011-01-01

    Many physiologic differences between children and adults may result in age-related changes in pharmacokinetics and pharmacodynamics. Factors such as gastric pH and emptying time, intestinal transit time, immaturity of secretion and activity of bile and pancreatic fluid among other factors determine the oral bioavailability of pediatric and adult populations. Anatomical, physiological and biochemical characteristics in children also affect the bioavailability of other routes of administration. Key factors explaining differences in drug distribution between the pediatric population and adults are membrane permeability, plasma protein binding and total body water. As far as drug metabolism is concerned, important differences have been found in the pediatric population compared with adults both for phase I and phase II metabolic enzymes. Immaturity of glomerular filtration, renal tubular secretion and tubular reabsorption at birth and their maturation determine the different excretion of drugs in the pediatric population compared to adults. PMID:24310425

  2. Adult survival and population growth rate in Colorado big brown bats (Eptesicus fuscus)

    USGS Publications Warehouse

    O'Shea, T.J.; Ellison, L.E.; Stanley, T.R.

    2011-01-01

    We studied adult survival and population growth at multiple maternity colonies of big brown bats (Eptesicus fuscus) in Fort Collins, Colorado. We investigated hypotheses about survival using information-theoretic methods and mark-recapture analyses based on passive detection of adult females tagged with passive integrated transponders. We constructed a 3-stage life-history matrix model to estimate population growth rate (??) and assessed the relative importance of adult survival and other life-history parameters to population growth through elasticity and sensitivity analysis. Annual adult survival at 5 maternity colonies monitored from 2001 to 2005 was estimated at 0.79 (95% confidence interval [95% CI] = 0.77-0.82). Adult survival varied by year and roost, with low survival during an extreme drought year, a finding with negative implications for bat populations because of the likelihood of increasing drought in western North America due to global climate change. Adult survival during winter was higher than in summer, and mean life expectancies calculated from survival estimates were lower than maximum longevity records. We modeled adult survival with recruitment parameter estimates from the same population. The study population was growing (?? = 1.096; 95% CI = 1.057-1.135). Adult survival was the most important demographic parameter for population growth. Growth clearly had the highest elasticity to adult survival, followed by juvenile survival and adult fecundity (approximately equivalent in rank). Elasticity was lowest for fecundity of yearlings. The relative importances of the various life-history parameters for population growth rate are similar to those of large mammals. ?? 2011 American Society of Mammalogists.

  3. Pathways of Expansion and Multiple Introductions Illustrated by Large Genetic Differentiation Among Worldwide Populations of the Southern House Mosquito

    DTIC Science & Technology

    2006-01-01

    in each PCI~. To pre\\’Cnl contamination with male DNf\\. female 010- domens were not used. The DNA cxtraction and peR prepa· rations invulving Ihe...mixes of males and females . Fur- IheHllor.... ,IS mentioned before, the microsalcllite loci lIsed in Ihi, stud\\’ arc not scx·linked. \\"el1 ;~fter we...IfHJ If~r.il·llt· PATHWAYS OF EXPANSION AND MULTIPLE INTRODUCTIONS ILLUSTRATED BY LARGE GENETIC DIFFERENTIATION AMONG WORLDWIDE POPULATIONS OF THE

  4. Exploiting mosquito sugar feeding to detect mosquito-borne pathogens

    PubMed Central

    Hall-Mendelin, Sonja; Ritchie, Scott A.; Johansen, Cheryl A.; Zborowski, Paul; Cortis, Giles; Dandridge, Scott; Hall, Roy A.; van den Hurk, Andrew F.

    2010-01-01

    Arthropod-borne viruses (arboviruses) represent a global public health problem, with dengue viruses causing millions of infections annually, while emerging arboviruses, such as West Nile, Japanese encephalitis, and chikungunya viruses have dramatically expanded their geographical ranges. Surveillance of arboviruses provides vital data regarding their prevalence and distribution that may be utilized for biosecurity measures and the implementation of disease control strategies. However, current surveillance methods that involve detection of virus in mosquito populations or sero-conversion in vertebrate hosts are laborious, expensive, and logistically problematic. We report a unique arbovirus surveillance system to detect arboviruses that exploits the process whereby mosquitoes expectorate virus in their saliva during sugar feeding. In this system, infected mosquitoes captured by CO2-baited updraft box traps are allowed to feed on honey-soaked nucleic acid preservation cards within the trap. The cards are then analyzed for expectorated virus using real-time reverse transcription-PCR. In field trials, this system detected the presence of Ross River and Barmah Forest viruses in multiple traps deployed at two locations in Australia. Viral RNA was preserved for at least seven days on the cards, allowing for long-term placement of traps and continuous collection of data documenting virus presence in mosquito populations. Furthermore no mosquito handling or processing was required and cards were conveniently shipped to the laboratory overnight. The simplicity and efficacy of this approach has the potential to transform current approaches to vector-borne disease surveillance by streamlining the monitoring of pathogens in vector populations. PMID:20534559

  5. A Field Study in Benin to Investigate the Role of Mosquitoes and Other Flying Insects in the Ecology of Mycobacterium ulcerans

    PubMed Central

    Zogo, Barnabas; Djenontin, Armel; Carolan, Kevin; Babonneau, Jeremy; Guegan, Jean-François; Eyangoh, Sara; Marion, Estelle

    2015-01-01

    Background Buruli ulcer, the third mycobacterial disease after tuberculosis and leprosy, is caused by the environmental mycobacterium M. ulcerans. There is at present no clear understanding of the exact mode(s) of transmission of M. ulcerans. Populations affected by Buruli ulcer are those living close to humid and swampy zones. The disease is associated with the creation or the extension of swampy areas, such as construction of dams or lakes for the development of agriculture. Currently, it is supposed that insects (water bugs and mosquitoes) are host and vector of M. ulcerans. The role of water bugs was clearly demonstrated by several experimental and environmental studies. However, no definitive conclusion can yet be drawn concerning the precise importance of this route of transmission. Concerning the mosquitoes, DNA was detected only in mosquitoes collected in Australia, and their role as host/vector was never studied by experimental approaches. Surprisingly, no specific study was conducted in Africa. In this context, the objective of this study was to investigate the role of mosquitoes (larvae and adults) and other flying insects in ecology of M. ulcerans. This study was conducted in a highly endemic area of Benin. Methodology/Principal Findings Mosquitoes (adults and larvae) were collected over one year, in Buruli ulcer endemic in Benin. In parallel, to monitor the presence of M. ulcerans in environment, aquatic insects were sampled. QPCR was used to detected M. ulcerans DNA. DNA of M. ulcerans was detected in around 8.7% of aquatic insects but never in mosquitoes (larvae or adults) or in other flying insects. Conclusion/Significance This study suggested that the mosquitoes don't play a pivotal role in the ecology and transmission of M. ulcerans in the studied endemic areas. However, the role of mosquitoes cannot be excluded and, we can reasonably suppose that several routes of transmission of M. ulcerans are possible through the world. PMID:26196901

  6. Geographic coupling of juvenile and adult habitat shapes spatial population dynamics of a coral reef fish.

    PubMed

    Huijbers, Chantal M; Nagelkerken, Ivan; Debrot, Adolphe O; Jongejans, Eelke

    2013-08-01

    Marine spatial population dynamics are often addressed with a focus on larval dispersal, without taking into account movement behavior of individuals in later life stages. Processes occurring during demersal life stages may also drive spatial population dynamics if habitat quality is perceived differently by animals belonging to different life stages. In this study, we used a dual approach to understand how stage-structured habitat use and dispersal ability of adults shape the population of a marine fish species. Our study area and focal species provided us with the unique opportunity to study a closed island population. A spatial simulation model was used to estimate dispersal distances along a coral reef that surrounds the island, while contributions of different nursery bays were determined based on otolith stable isotope signatures of adult reef fish. The model showed that adult dispersal away from reef areas near nursery bays is limited. The results further show that different bays contributed unequally to the adult population on the coral reef, with productivity of juveniles in bay nursery habitat determining the degree of mixing among local populations on the reef and with one highly productive area contributing most to the island's reef fish population. The contribution of the coral reef as a nursery habitat was minimal, even though it had a much larger surface area. These findings indicate that the geographic distribution of nursery areas and their productivity are important drivers for the spatial distribution patterns of adults on coral reefs. We suggest that limited dispersal of adults on reefs can lead to a source-sink structure in the adult stage, where reefs close to nurseries replenish more isolated reef areas. Understanding these spatial population dynamics of the demersal phase of marine animals is of major importance for the design and placement of marine reserves, as nursery areas contribute differently to maintain adult populations.

  7. Design and Testing of Novel Lethal Ovitrap to Reduce Populations of Aedes Mosquitoes: Community-Based Participatory Research between Industry, Academia and Communities in Peru and Thailand

    PubMed Central

    Yukich, Josh; Soonthorndhada, Amara; Giron, Maziel; Apperson, Charles S.; Ponnusamy, Loganathan; Schal, Coby; Morrison, Amy C.; Keating, Joseph; Wesson, Dawn M.

    2016-01-01

    Background Dengue virus (and Chikungunya and Zika viruses) is transmitted by Aedes aegypti and Aedes albopictus mosquitoes and causes considerable human morbidity and mortality. As there is currently no vaccine or chemoprophylaxis to protect people from dengue virus infection, vector control is the only viable option for disease prevention. The purpose of this paper is to illustrate the design and placement process for an attractive lethal ovitrap to reduce vector populations and to describe lessons learned in the development of the trap. Methods This study was conducted in 2010 in Iquitos, Peru and Lopburi Province, Thailand and used an iterative community-based participatory approach to adjust design specifications of the trap, based on community members’ perceptions and feedback, entomological findings in the lab, and design and research team observations. Multiple focus group discussions (FGD) were held over a 6 month period, stratified by age, sex and motherhood status, to inform the design process. Trap testing transitioned from the lab to within households. Results Through an iterative process of working with specifications from the research team, findings from the laboratory testing, and feedback from FGD, the design team narrowed trap design options from 22 to 6. Comments from the FGD centered on safety for children and pets interacting with traps, durability, maintenance issues, and aesthetics. Testing in the laboratory involved releasing groups of 50 gravid Ae. aegypti in walk-in rooms and assessing what percentage were caught in traps of different colors, with different trap cover sizes, and placed under lighter or darker locations. Two final trap models were mocked up and tested in homes for a week; one model was the top choice in both Iquitos and Lopburi. Discussion The community-based participatory process was essential for the development of novel traps that provided effective vector control, but also met the needs and concerns of community

  8. MAN, MOSQUITOES AND MICROBES.

    ERIC Educational Resources Information Center

    SCHOONOVER, ROBERT A.

    THE CONTROL OF MOSQUITOES IS A MATTER OF INCREASING CONCERN IN THE STATE OF FLORIDA. A BRIEF DESCRIPTION OF THE LIFE CYCLE, VARIOUS SPECIES, CONTROL, AND DESCRIPTION OF DISEASES TRANSMITTED BY THE MOSQUITO WAS PRESENTED. THE ARTICLE CONCLUDED THAT MOSQUITO CONTROL IS NOT ONLY A HEALTH PROBLEM, BUT ALSO A MATTER OF IMPROVED ECONOMICS IN RELATION TO…

  9. Mosquito Life Cycle

    EPA Pesticide Factsheets

    Knowing the stages of the mosquito's life will help you prevent mosquitoes around your home and help you choose the right pesticides for your needs, if you decide to use them. All mosquito species go through four distinct stages during their live cycle.

  10. Prevalence of Chronic Medical Conditions in Adults with Mental Retardation: Comparison with the General Population.

    ERIC Educational Resources Information Center

    Kapell, Deborah; Nightingale, Beryle; Rodriguez, Ana; Lee, Joseph H.; Zigman, Warren B.; Schupf, Nicole

    1998-01-01

    A study interviewed caregivers and reviewed medical records of 278 adults with mental retardation with and without Down syndrome. The adults with mental retardation had age-related disorders comparable to those in the general population, but there was an increased frequency of thyroid disorders, nonischemic heart disorders, and sensory impairment.…

  11. The National Blueprint for Promoting Physical Activity in the Mid-Life and Older Adult Population

    ERIC Educational Resources Information Center

    Chodzko-Zajko, Wojtek; Sheppard, Lisa; Senior, Jane; Park, Chae-Hee; Mockenhaupt, Robin; Bazzarre, Terry

    2005-01-01

    The National Blueprint: Increasing Physical Activity Among Adults Age 50 and Older was designed to develop a national strategy for the promotion of physically active lifestyles among the mid-life and older adult population. The Blueprint identifies barriers to physical activity in the areas of research, home and community programs, medical…

  12. Visual Function and Visual Acuity in an Urban Adult Population.

    ERIC Educational Resources Information Center

    Katz, J.; Tielsch, J. M.

    1996-01-01

    A survey of 6,850 adults age 40 or over concerning the effects of poor vision found that difficulties with reading or other near-vision activities were the most common complaint. One-fourth reported limitations in activities because of poor vision. Factors associated with loss of visual function were general health status, educational level, and…

  13. Engineering Plasmodium-refractory phenotypes in mosquitoes.

    PubMed

    Nirmala, Xavier; James, Anthony A

    2003-09-01

    A remarkable number of effector mechanisms have been developed for interfering with malaria parasite development in mosquitoes. These effector mechanisms affect different aspects of parasite biology and therefore could be targeted synergistically to reduce the probability of emergence of parasite resistance to any one mechanism. The use of these mechanisms will depend on how efficiently and safely they can be introduced into existing mosquito populations.

  14. Vector Competence of Mosquitoes for Arboviruses

    DTIC Science & Technology

    1989-07-30

    ml) on the titers of three alphaviruses , Sindbis(A), western equine encephalomyelitis (B), Venezuelan equine encephalomyelitis (C), and the...population have been delineated and discussed with reference to the mosquito, Culex tarsalis, and the alphavirus , western equine encephalomyelitis (WEE...mechanism that appears to control WEE viral replication (Hardy et al., 1983; Kramer et al., 1989; Ann. Prog. Rpt., 1988). The ability of a mosquito to

  15. Efficacy of Commercial Mosquito Traps in Capturing Phlebotomine Sand Flies in Egypt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adult mosquito traps of four types that are marketed for homeowner use in residential settings were compared with a standard CDC light trap for efficacy in collecting phlebotomine sand flies. We evaluated the Mosquito MagnetTM Pro (MMP), the SentinelTM 360 mosquito trap (S360), the BG-SentinelTM mo...

  16. Insecticide resistance spectra and resistance mechanisms in populations of Japanese encephalitis vector mosquitoes, Culex tritaeniorhynchus and Cx. gelidus, in Sri Lanka.

    PubMed

    Karunaratne, S H; Hemingway, J

    2000-12-01

    Culex tritaeniorhynchus Giles and Cx. gelidus Theobald (Diptera: Culicidae), both vectors of Japanese encephalitis, were collected in 1984 and 1998 from two disease endemic localities in Sri Lanka: Anaradhapura and Kandy. Using wild-caught adult mosquitoes from light traps, log dosage-probit mortality curves for insecticide bioassays were obtained for three insecticides: malathion (organophosphate), propoxur (carbamate) and permethrin (pyrethroid). LD50 values showed that, in 1998, Cx. tritaeniorhynchus was -100-fold more resistant to malathion and 10-fold more resistant to propoxur than was Cx. gelidus. This difference was attributed to Cx. tritaeniorhynchus breeding mostly in irrigated rice paddy fields, where it would have been exposed to pesticide selection pressure, whereas Cx. gelidus breeds in other types of aquatic habitats less prone to pesticide applications. Resistance in Cx. tritaeniorhynchus increased between 1984 and 1998, whereas Cx. gelidus remained predominantly susceptible. Propoxur inhibition of acetylcholinesterase (AChE) activity (the target site of organophosphates and carbamates) indicated that in 1998, frequencies of insensitive AChE-based resistance were 9% in Cx. gelidus and 2-23% in Cx. tritaeniorhynchus, whereas in 1984 this resistance mechanism was detected only in 2% of the latter species from Anaradhapura. The AChE inhibition coefficient (ki) with propoxur was 1.86+/-0.24 x 10(5) M(-)1 min(-1) for Cx. tritaeniorhynchus from Anaradhapura in 1998. Both species were tested for activity levels of detoxifying glutathione S-transferases (GSTs) and malathion-specific as well as general carboxylesterases. High activities of GSTs and carboxylesterases were detected in Cx. tritaeniorhynchus but not Cx. gelidus. Malathion-specific carboxylesterase was absent from both species. Native polyacrylamide gel electrophoresis resolved two elevated general carboxylesterases, CtrEstbeta1 and CtrEstalpha1, from Cx. tritaeniorhynchus and none from Cx

  17. Well-Being in an Adult Swedish Population

    ERIC Educational Resources Information Center

    Hansson, Anna; Hilleras, Pernilla; Forsell, Yvonne

    2005-01-01

    Objectives: The aim of this study was to see if earlier findings about factors associated with well-being could be replicated in a large population-based sample in Sweden. To the best of our knowledge, no research on well-being has been conducted on such a large population in a country, which by most standards is regarded as one of the most…

  18. Convergence between a mosquito-eating predator's natural diet and its prey-choice behaviour

    PubMed Central

    Jackson, Robert R.; Deng, Chan

    2016-01-01

    On the basis of 1115 records of Evarcha culicivora feeding in the field, we can characterize this East African jumping spider (Salticidae) as being distinctively stenophagic. We can also, on the basis of laboratory prey-choice experiments, characterize E. culicivora as having a specialized prey-classification system and a hierarchy of innate preferences for various categories of mosquitoes and other arthropods. Prey from the field belonged to 10 arthropod orders, but 94.5% of the prey records were dipterans. Mosquitoes were the dominant prey (80.2% of the records), with the majority (82.9%) of the mosquitoes being females, and thereafter midges were the most common prey (9.2% of the records). Preference profiles that were determined from experiments showed strong convergence with natural diet in some, but not all, instances. In experiments, E. culicivora adults appeared to distinguish between six prey categories and juveniles between seven, with blood-carrying anopheline female mosquitoes being ranked highest in preference. For adults, this was followed by blood-carrying culicine female mosquitoes and then anopheline female mosquitoes not carrying blood, but these two preferences were reversed for juveniles. Moreover, for juveniles, but not for adults, anopheline male mosquitoes seem to be a distinct prey category ranked in preference after blood-carrying culicine females and, for both adults and juveniles, preference for midges is evident when the alternatives are not mosquitoes. These findings illustrate the importance of going beyond simply specifying preferred prey categories when characterizing predators as ‘specialized’ and a need to make clear conceptual distinctions between a predator's natural diet, the prey categories that are relevant to the predator, and the predator's prey-choicebehaviour. PMID:28083103

  19. Evaluation of Mosquito Breeding on Corps of Engineers Properties Adjacent to Williston, North Dakota

    DTIC Science & Technology

    1990-11-01

    12 4 Dipper used for collecting samples of mosquito larvae ............. .13 5 Center for Disease Control light traps used to collect adult...floodplain environment. 3. Recent control efforts by the Williston Vector Control District No. 1 (WVCD) have centered on the adults. This type of treatment...short-term control method and is usually a reaction to ex- cessive levels of adult mosquitoes or a mosquito-related medical emergency situation. 4

  20. Dissociative Symptoms and Mother's Marital Status in Young Adult Population

    PubMed Central

    Bob, Petr; Selesova, Petra; Raboch, Jiri; Kukla, Lubomir

    2015-01-01

    Abstract Current findings suggest that mother's marital status indicating father's absence or conflicting relationship to father may be specifically related to dissociation and other stress-related symptoms. We have assessed relationships of mother's marital status, dissociative symptoms, and other psychopathological manifestations in a sample of 19 years’ old young adults (N = 364) participating in European longitudinal study (European Longitudinal Study of Parenthood and Childhood). The results show clinically significant manifestations of dissociative symptoms in young adult men whose mothers were fatherless and in women whose mothers were re-married. Other psychopathological symptoms did not reach clinically significant manifestations. The results suggest that significant factor related to high level of dissociative symptoms in men growing in fatherless families might be linked with disturbed and conflicting attachment to a father's figure and pathological dependent attachment to mother. In women dissociative symptoms likely are linked to conflicting relationship between mother and daughter associated with stepfather’ presence in the family. PMID:25590849

  1. Grammatical Class Effects Across Impaired Child and Adult Populations

    PubMed Central

    Kambanaros, Maria; Grohmann, Kleanthes K.

    2015-01-01

    The aims of this study are to compare quantitative and qualitative differences for noun/verb retrieval across language-impaired groups, examine naming errors with reference to psycholinguistic models of word processing, and shed light on the nature of the naming deficit as well as determine relevant group commonalities and differences. This includes an attempt to establish whether error types differentiate language-impaired children from adults, to determine effects of psycholinguistic variables on naming accuracies, and to link the results to genetic mechanisms and/or neural circuitry in the brain. A total of 89 (language-)impaired participants took part in this report: 24 adults with acquired aphasia, 20 adults with schizophrenia-spectrum disorder, 31 adults with relapsing-remitting multiple sclerosis, and 14 children with specific language impairment. The results of simultaneous multiple regression analyses for the errors in verb naming compared to the psycholinguistic variables for all language-impaired groups are reported and discussed in relation to models of lexical processing. This discussion will lead to considerations of genetic and/or neurobiological underpinnings: Presence of the noun–verb dissociation in focal and non-focal brain impairment make localization theories redundant, but support for wider neural network involvement.The patterns reported cannot be reduced to any one level of language processing, suggesting multiple interactions at different levels (e.g., receptive vs. expressive language abilities).Semantic-conceptual properties constrain syntactic properties with implications for phonological word form retrieval.Competition needs to be resolved at both conceptual and phonological levels of representation. Moreover, this study may provide a cross-pathological baseline that can be probed further with respect to recent suggestions concerning a reconsideration of open- vs. closed-class items, according to which verbs may actually fall into the

  2. Engineered mosquitoes to fight mosquito borne diseases: not a merely technical issue.

    PubMed

    Favia, Guido

    2015-01-01

    Malaria, dengue and other mosquito-borne diseases pose dramatic problems of public health, particularly in tropical and sub-tropical countries. Historically, vector control has been one of the most successfully strategies to eradicate some mosquito-borne diseases, as witnessed by malaria eradication in Mediterranean regions such as Italy and Greece. Vector control through insecticides has been used worldwide; unfortunately, it is losing effectiveness due to spread of resistances. Control of mosquito-borne diseases through field-releases of genetically engineered mosquitoes is an innovative and now feasible approach. Genetically modified mosquitoes have already been released into the wild in some regions, and protocols for this release are on hand in others. Local authorities are vigilant that transgenic insects in the field are safe for human and animal populations, and the public engagement in every control program is assuming a central role.

  3. Plant extracts as potential mosquito larvicides

    PubMed Central

    Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

    2012-01-01

    Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain and adverse effects on environmental quality and non target organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed. PMID:22771587

  4. Optimal control strategy of malaria vector using genetically modified mosquitoes.

    PubMed

    Rafikov, M; Bevilacqua, L; Wyse, A P P

    2009-06-07

    The development of transgenic mosquitoes that are resistant to diseases may provide a new and effective weapon of diseases control. Such an approach relies on transgenic mosquitoes being able to survive and compete with wild-type populations. These transgenic mosquitoes carry a specific code that inhibits the plasmodium evolution in its organism. It is said that this characteristic is hereditary and consequently the disease fades away after some time. Once transgenic mosquitoes are released, interactions between the two populations and inter-specific mating between the two types of mosquitoes take place. We present a mathematical model that considers the generation overlapping and variable environment factors. Based on this continuous model, the malaria vector control is formulated and solved as an optimal control problem, indicating how genetically modified mosquitoes should be introduced in the environment. Numerical simulations show the effectiveness of the proposed control.

  5. Mermithid nematodes found in adult Anopheles from southeastern Senegal

    PubMed Central

    2012-01-01

    Background Over two dozen mermithid nematodes have been described parasitizing mosquitoes worldwide, however, only two species were found in Africa. Mermithid nematodes kill their mosquito host upon emergence, which suggests that they could be developed as biological control agents of mosquitoes. Both Romanomermis culicivorax and Romanomermis iyengari have been reared for mass release to control numerous Anopheles species vector populations, and in one instance this may have led to reduced malaria prevalence in a human population. Methods Anopheles mosquitoes were collected during a malaria study in southeastern Senegal. Two different adult blood fed mosquitoes had a single mermithid nematode emerge from their anus while they were being held post-capture. Primers from the 18 S rDNA were developed to sequence nematode DNA and screen mosquitoes for mermithid DNA. 18 S rDNA from the Senegalese mermithid and other mermithid entries in GenBank were used to create a Maximum Parsimony tree of the Mermithidae family. Results The mermithid was present in 1.8% (10/551) of the sampled adult Anopheles species in our study area. The mermithid was found in An. gambiae s.s., An. funestus, and An. rufipes from the villages of Ndebou, Boundoucondi, and Damboucoye. Maximum parsimony analysis confirmed that the nematode parasites found in Anopheles were indeed mermithid parasites, and of the mermithid sequences available in GenBank, they are most closely related to Strelkovimermis spiculatus. Conclusions To our knowledge, this is the first report of mermithids from adult Anopheles mosquitoes in Senegal. The mermithid appears to infect Anopheles mosquitoes that develop in diverse larval habitats. Although maximum parsimony analysis determined the mermithid was closely related to Strelkovimermis spiculatus, several characteristics of the mermithid were more similar to the Empidomermis genus. Future mermithid isolations will hopefully allow: formal taxonomic identification

  6. Estimates and Projections of the Limited English Proficient Adult Population in Need of Employment Training.

    ERIC Educational Resources Information Center

    Willette, JoAnne; And Others

    A study estimated the size of the population of adults and out-of-school youth with limited English proficiency (LEP) who need vocational education and related employment services and projected the size of this population from the time of the study to the year 2000. Research procedures included a literature review, an analysis of 1980 U.S. census…

  7. Hey! A Mosquito Bit Me!

    MedlinePlus

    ... dientes Video: Getting an X-ray Hey! A Mosquito Bit Me! KidsHealth > For Kids > Hey! A Mosquito ... español ¡Ay! ¡Me picó un mosquito! What's a Mosquito? A mosquito (say: mus-KEE-toe) is an ...

  8. Hey! A Mosquito Bit Me!

    MedlinePlus

    ... What Happens in the Operating Room? Hey! A Mosquito Bit Me! KidsHealth > For Kids > Hey! A Mosquito ... español ¡Ay! ¡Me picó un mosquito! What's a Mosquito? A mosquito (say: mus-KEE-toe) is an ...

  9. Adult hippocampal neurogenesis in natural populations of mammals.

    PubMed

    Amrein, Irmgard

    2015-05-01

    This review will discuss adult hippocampal neurogenesis in wild mammals of different taxa and outline similarities with and differences from laboratory animals. It begins with a review of evidence for hippocampal neurogenesis in various mammals, and shows the similar patterns of age-dependent decline in cell proliferation in wild and domesticated mammals. In contrast, the pool of immature neurons that originate from proliferative activity varies between species, implying a selective advantage for mammals that can make use of a large number of these functionally special neurons. Furthermore, rapid adaptation of hippocampal neurogenesis to experimental challenges appears to be a characteristic of laboratory rodents. Wild mammals show species-specific, rather stable hippocampal neurogenesis, which appears related to demands that characterize the niche exploited by a species rather than to acute events in the life of its members. Studies that investigate adult neurogenesis in wild mammals are not numerous, but the findings of neurogenesis under natural conditions can provide new insights, and thereby also address the question to which cognitive demands neurogenesis may respond during selection.

  10. Paratransgenesis: a promising new strategy for mosquito vector control.

    PubMed

    Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

    2015-06-24

    The three main mosquito genera, Anopheles, Aedes and Culex, transmit respectively malaria, dengue and lymphatic filariasis. Current mosquito control strategies have proved unsuccessful, and there still is a substantial number of morbidity and mortality from these diseases. Genetic control methods have now arisen as promising alternative strategies, based on two approaches: the replacement of a vector population by disease-refractory mosquitoes and the release of mosquitoes carrying a lethal gene to suppress target populations. However, substantial hurdles and limitations need to be overcome if these methods are to be used successfully, the most significant being that a transgenic mosquito strain is required for every target species, making genetically modified mosquito strategies inviable when there are multiple vector mosquitoes in the same area. Genetically modified bacteria capable of colonizing a wide range of mosquito species may be a solution to this problem and another option for the control of these diseases. In the paratransgenic approach, symbiotic bacteria are genetically modified and reintroduced in mosquitoes, where they express effector molecules. For this approach to be used in practice, however, requires a better understanding of mosquito microbiota and that symbiotic bacteria and effector molecules be identified. Paratransgenesis could prove very useful in mosquito species that are inherently difficult to transform or in sibling species complexes. In this approach, a genetic modified bacteria can act by: (a) causing pathogenic effects in the host; (b) interfering with the host's reproduction; (c) reducing the vector's competence; and (d) interfering with oogenesis and embryogenesis. It is a much more flexible and adaptable approach than the use of genetically modified mosquitoes because effector molecules and symbiotic bacteria can be replaced if they do not achieve the desired result. Paratransgenesis may therefore become an important integrated

  11. Does cannibalism of larvae by adults affect settlement and connectivity of mussel populations?

    NASA Astrophysics Data System (ADS)

    Porri, Francesca; Jordaan, Tembisa; McQuaid, Christopher D.

    2008-09-01

    Intertidal population dynamics are driven by a complex series of processes, including larval supply and the possibility of larval predation by benthic animals such as filter-feeders. We hypothesised that cannibalism by adults could play a major role in the population connectivity of mussel populations by removing larvae as they attempt to settle in the adult habitat. Specifically, we tested hypotheses that consumption of mussel larvae by adults removes a significant proportion of potential settlers and is influenced by both settlement intensity and tidal state (flooding or ebbing). Predation of mussel larvae by adult mussels was investigated on incoming and ebbing tides during four spring tides by analysing the gut contents of adult Perna perna and Mytilus galloprovincialis collected from the low intertidal mussel zone between October 2005 and January 2006. Consumption rates were then compared with estimates of successful settler densities on natural beds. The results showed that mortality of competent mussel larvae through adult ingestion removes up to 77% a of potential settlers. Rates of larval consumption were highest during months of intense settlement, suggesting that mussels feed opportunistically, filtering a relatively fixed volume of water and removing particles, including larvae, in proportion to their densities in the water. Rates of larviphagy were also higher during receding than incoming tides. We suggest that this is due to changes in larval density or, more probably, in adult filtration efficiency that are related to the state of the tide. Despite significant effects of both tidal state and settlement intensity on rates of larval ingestion, neither had a significant effect on the proportion of potential settlers removed. During settlement more than half of all potential settlers are lost through cannibalism, with potentially serious consequences for population maintenance. The results highlight the paradoxical nature of the evolution of settlement

  12. Estimating total population size for adult female sea turtles: Accounting for non-nesters

    USGS Publications Warehouse

    Kendall, W.L.; Richardson, J.I.; Rees, Alan F.

    2008-01-01

    Assessment of population size and changes therein is important to sea turtle management and population or life history research. Investigators might be interested in testing hypotheses about the effect of current population size or density (number of animals per unit resource) on future population processes. Decision makers might want to determine a level of allowable take of individual turtles of specified life stage. Nevertheless, monitoring most stages of sea turtle life histories is difficult, because obtaining access to individuals is difficult. Although in-water assessments are becoming more common, nesting females and their hatchlings remain the most accessible life stages. In some cases adult females of a given nesting population are sufficiently philopatric that the population itself can be well defined. If a well designed tagging study is conducted on this population, survival, breeding probability, and the size of the nesting population in a given year can be estimated. However, with published statistical methodology the size of the entire breeding population (including those females skipping nesting in that year) cannot be estimated without assuming that each adult female in this population has the same probability of nesting in a given year (even those that had just nested in the previous year). We present a method for estimating the total size of a breeding population (including nesters those skipping nesting) from a tagging study limited to the nesting population, allowing for the probability of nesting in a given year to depend on an individual's nesting status in the previous year (i.e., a Markov process). From this we further develop estimators for rate of growth from year to year in both nesting population and total breeding population, and the proportion of the breeding population that is breeding in a given year. We also discuss assumptions and apply these methods to a breeding population of hawksbill sea turtles (Eretmochelys imbricata) from

  13. Evolution of increased adult longevity in Drosophila melanogaster populations selected for adaptation to larval crowding.

    PubMed

    Shenoi, V N; Ali, S Z; Prasad, N G

    2016-02-01

    In holometabolous animals such as Drosophila melanogaster, larval crowding can affect a wide range of larval and adult traits. Adults emerging from high larval density cultures have smaller body size and increased mean life span compared to flies emerging from low larval density cultures. Therefore, adaptation to larval crowding could potentially affect adult longevity as a correlated response. We addressed this issue by studying a set of large, outbred populations of D. melanogaster, experimentally evolved for adaptation to larval crowding for 83 generations. We assayed longevity of adult flies from both selected (MCUs) and control populations (MBs) after growing them at different larval densities. We found that MCUs have evolved increased mean longevity compared to MBs at all larval densities. The interaction between selection regime and larval density was not significant, indicating that the density dependence of mean longevity had not evolved in the MCU populations. The increase in longevity in MCUs can be partially attributed to their lower rates of ageing. It is also noteworthy that reaction norm of dry body weight, a trait probably under direct selection in our populations, has indeed evolved in MCU populations. To the best of our knowledge, this is the first report of the evolution of adult longevity as a correlated response of adaptation to larval crowding.

  14. Caregiver Abuse of Chicago Chinese Older Adults in a Community-Dwelling Population

    PubMed Central

    Dong, Xin Qi; Li, Ge

    2016-01-01

    Objectives This study aimed to examine the prevalence and correlates of elder abuse reported by adult children among U.S Chinese populations. Method A community-based participatory research approach was implemented. A total of 548 Chinese adult children aged 21 years and over participated in this study. Elder abuse reported by adult children was assessed using Caregiver Abuse Screen (CASE). Results This study found a prevalence of 59.8%for elder abuse among 548 adult children. Younger age (r = −0.10, p < .05), higher level of education (r = 0.20, p < .001), higher income (r = 0.14, p < .01), more years in the U.S. (r = 0.12, p < .05), not born in Mainland China (r = −0.13, p < .01), and English-speaking (r = 0.16, p < .001) were positively correlated with elder abuse reported by adult children. Discussion Elder abuse by adult children is prevalent among U.S. Chinese populations. It is necessary for researchers, health care providers and policy makers to put more attention on elder abuse by adult children. Longitudinal research is needed to explore the risk factors associated with elder abuse by adult children. Health care providers should improve detection of elder abuse and support at-risk caregivers. Policy makers may consider cultural sensitive approaches to address elder abuse. PMID:27606358

  15. Spatial and Temporal Distributions of Mosquito Adulticide in Houston during Spraying Season

    NASA Astrophysics Data System (ADS)

    Usenko, S.; Clark, A. E.; Yoon, S.; Sheesley, R. J.

    2015-12-01

    It is a common practice for urban areas in the south to control the mosquito population through the routine spraying of pesticides utilizing ultra-low volume (ULV) foggers, either aerially or from trucks. Adult mosquitoes are known disease-borne vectors, including, but not limited to, West Nile Virus. Common mosquito adulticides include Permethrin (a pyrethroid) which is a neurotoxin. The EPA has labelled this pesticide good for mosquito treatment due to low cost, high effectiveness and low pest resistance. Permethrin is released directly into the atmosphere during active ULV fogger spraying, resulting in potentially significantly elevated atmospheric concentrations for hours to days after spray event. The metropolitan area of Houston, TX has a population of nearly 6 million people, making it the fourth most populous city in the U.S., and covers over 9000 square miles. During the DISCOVER-AQ sampling campaign in September 2013, nearly 300 atmospheric particular matter samples were collected during the month-long sampling campaign at four different locations in the Houston metropolitan area. Both total suspended particle (TSP) and particulate matter less than 2.5 microns in aerodynamic diameter (PM2.5) samples were collected, the latter of which is more readily inhaled and presents a greater risk to human health. Harris County, the main county of the Houston metropolitan area, controls mosquito for ~4-7 months, annually, covering the summer months. During 2013, Harris County utilized Permethrin as one of two pesticides in a weekly rotation from April to October. Proposed daily ULV treatment plans are published online on a neighborhood scale (Zip Code). Preliminary atmospheric concentrations show that Permethrin has been detected coinciding with days when treatment was proposed by the county. During or directly after use, atmospheric concentration of Permethrin were measuring at typically >10 ng m-3, but as high as 90 ng m-3. Atmospheric concentrations were also

  16. Tips to Prevent Mosquito Bites

    EPA Pesticide Factsheets

    Using the right insect repellent and other preventive actions can discourage mosquitoes from landing on you. Tips include removing mosquito habitats such as standing water, minimizing exposed skin, and staying indoors while mosquitoes are most active.

  17. Bronchodilator Responsiveness and Reported Respiratory Symptoms in an Adult Population

    PubMed Central

    Tan, Wan C.; Bourbeau, Jean; Hernandez, Paul; Chapman, Kenneth R.; Cowie, Robert; FitzGerald, J. Mark; Aaron, Shawn; Marciniuk, Darcy D.; Maltais, Francois; Buist, A. Sonia; O’Donnell, Denis E.; Sin, Don D.

    2013-01-01

    Background The relationship between patient-reported symptoms and objective measures of lung function is poorly understood. Aim To determine the association between responsiveness to bronchodilator and respiratory symptoms in random population samples. Methods 4669 people aged 40 years and older from 8 sites in Canada completed interviewer-administered respiratory questionnaires and performed spirometry before and after administration of 200 ug of inhaled salbutamol. The effect of anthropometric variables, smoking exposure and doctor-diagnosed asthma (DDA) on bronchodilator responsiveness in forced expiratory volume in 1 second (FEV1) and in forced vital capacity (FVC) were evaluated. Multiple logistic regression was used to test for association between quintiles of increasing changes in FEV1 and in FVC after bronchodilator and several respiratory symptoms. Results Determinants of bronchodilator change in FEV1 and FVC included age, DDA, smoking, respiratory drug use and female gender [p<0.005 to p<0.0001 ]. In subjects without doctor-diagnosed asthma or COPD, bronchodilator response in FEV1 was associated with wheezing [p for trend<0.0001], while bronchodilator response for FVC was associated with breathlessness. [p for trend <0.0001]. Conclusions Bronchodilator responsiveness in FEV1 or FVC are associated with different respiratory symptoms in the community. Both flow and volume bronchodilator responses are useful parameters which together can be predictive of both wheezing and breathlessness in the general population. PMID:23554960

  18. Mathematical model in controlling dengue transmission with sterile mosquito strategies

    NASA Astrophysics Data System (ADS)

    Aldila, D.; Nuraini, N.; Soewono, E.

    2015-09-01

    In this article, we propose a mathematical model for controlling dengue disease transmission with sterile mosquito techniques (SIT). Sterile male introduced from lab in to habitat to compete with wild male mosquito for mating with female mosquito. Our aim is to displace gradually the natural mosquito from the habitat. Mathematical model analysis for steady states and the basic reproductive ratio are performed analytically. Numerical simulation are shown in some different scenarios. We find that SIT intervention is potential to controlling dengue spread among humans population

  19. Climatic Factors Driving Invasion of the Tiger Mosquito (Aedes albopictus) into New Areas of Trentino, Northern Italy

    PubMed Central

    Castellani, Cristina; Arnoldi, Daniele; Rizzoli, Annapaola

    2011-01-01

    Background The tiger mosquito (Aedes albopictus), vector of several emerging diseases, is expanding into more northerly latitudes as well as into higher altitudes in northern Italy. Changes in the pattern of distribution of the tiger mosquito may affect the potential spread of infectious diseases transmitted by this species in Europe. Therefore, predicting suitable areas of future establishment and spread is essential for planning early prevention and control strategies. Methodology/Principal Findings To identify the areas currently most suitable for the occurrence of the tiger mosquito in the Province of Trento, we combined field entomological observations with analyses of satellite temperature data (MODIS Land Surface Temperature: LST) and human population data. We determine threshold conditions for the survival of overwintering eggs and for adult survival using both January mean temperatures and annual mean temperatures. We show that the 0°C LST threshold for January mean temperatures and the 11°C threshold for annual mean temperatures provide the best predictors for identifying the areas that could potentially support populations of this mosquito. In fact, human population density and distance to human settlements appear to be less important variables affecting mosquito distribution in this area. Finally, we evaluated the future establishment and spread of this species in relation to predicted climate warming by considering the A2 scenario for 2050 statistically downscaled at regional level in which winter and annual temperatures increase by 1.5 and 1°C, respectively. Conclusions/Significance MODIS satellite LST data are useful for accurately predicting potential areas of tiger mosquito distribution and for revealing the range limits of this species in mountainous areas, predictions which could be extended to an European scale. We show that the observed trend of increasing temperatures due to climate change could facilitate further invasion of Ae. albopictus

  20. Temperament profiles in personality disorders among a young adult population.

    PubMed

    Kantojärvi, Liisa; Miettunen, Jouko; Veijola, Juha; Läksy, Kristian; Karvonen, Juha T; Ekelund, Jesper; Järvelin, Marjo-Riitta; Lichtermann, Dirk; Joukamaa, Matti

    2008-01-01

    The objective of this study was to describe the temperament dimension profiles assessed by the Temperament and Character Inventory (TCI) among young adults with the DSM-III-R personality disorder (PD). Our hypothesis was that PD clusters and separate PDs can be distinguished from one another by their specific temperament profiles. As a part of the 31-year follow-up survey of the prospective Northern Finland 1966 Birth Cohort, the cohort members living in the city of Oulu at the age of 31 years (n=1609) were invited to participate in a two-phase field study. The Structured Clinical Interview for DSM-III-R for PDs (SCID-II) was used as diagnostic instrument. The final study sample consisted of the 1311 subjects who had completed the Hopkins Symptom Check List-25 questionnaire for screening and had given a written informed consent. Of the 321 SCID interviewed subjects, 74 met the criteria for at least one PD and had completed the TCI. The mean TCI scores of subjects with PD and control subjects without PD (n=910) were compared. Low Novelty Seeking, high Harm Avoidance and low Reward Dependence characterized cluster A and C PDs. Subjects with a cluster B PD did not differ from controls, except for Novelty Seeking, which was high. The temperament dimensions could not distinguish different PDs very well, with the only exception of persons with obsessive-compulsive PD. PD clusters were associated with different profiles of temperament, lending some support for Cloninger's typology.

  1. Mortality Among Adults With Intellectual Disability in England: Comparisons With the General Population

    PubMed Central

    Hosking, Fay J.; Shah, Sunil M.; Harris, Tess; DeWilde, Stephen; Beighton, Carole; Cook, Derek G.

    2016-01-01

    Objectives. To describe mortality among adults with intellectual disability in England in comparison with the general population. Methods. We conducted a cohort study from 2009 to 2013 using data from 343 general practices. Adults with intellectual disability (n = 16 666; 656 deaths) were compared with age-, gender-, and practice-matched controls (n = 113 562; 1358 deaths). Results. Adults with intellectual disability had higher mortality rates than controls (hazard ratio [HR] = 3.6; 95% confidence interval [CI] = 3.3, 3.9). This risk remained high after adjustment for comorbidity, smoking, and deprivation (HR = 3.1; 95% CI = 2.7, 3.4); it was even higher among adults with intellectual disability and Down syndrome or epilepsy. A total of 37.0% of all deaths among adults with intellectual disability were classified as being amenable to health care intervention, compared with 22.5% in the general population (HR = 5.9; 95% CI = 5.1, 6.8). Conclusions. Mortality among adults with intellectual disability is markedly elevated in comparison with the general population, with more than a third of deaths potentially amenable to health care interventions. This mortality disparity suggests the need to improve access to, and quality of, health care among people with intellectual disability. PMID:27310347

  2. The Impact of Wolbachia on Virus Infection in Mosquitoes

    PubMed Central

    Johnson, Karyn N.

    2015-01-01

    Mosquito-borne viruses such as dengue, West Nile and chikungunya viruses cause significant morbidity and mortality in human populations. Since current methods are not sufficient to control disease occurrence, novel methods to control transmission of arboviruses would be beneficial. Recent studies have shown that virus infection and transmission in insects can be impeded by co-infection with the bacterium Wolbachia pipientis. Wolbachia is a maternally inherited endosymbiont that is commonly found in insects, including a number of mosquito vector species. In Drosophila, Wolbachia mediates antiviral protection against a broad range of RNA viruses. This discovery pointed to a potential strategy to interfere with mosquito transmission of arboviruses by artificially infecting mosquitoes with Wolbachia. This review outlines research on the prevalence of Wolbachia in mosquito vector species and the impact of antiviral effects in both naturally and artificially Wolbachia-infected mosquitoes. PMID:26556361

  3. The Impact of Wolbachia on Virus Infection in Mosquitoes.

    PubMed

    Johnson, Karyn N

    2015-11-04

    Mosquito-borne viruses such as dengue, West Nile and chikungunya viruses cause significant morbidity and mortality in human populations. Since current methods are not sufficient to control disease occurrence, novel methods to control transmission of arboviruses would be beneficial. Recent studies have shown that virus infection and transmission in insects can be impeded by co-infection with the bacterium Wolbachia pipientis. Wolbachia is a maternally inherited endosymbiont that is commonly found in insects, including a number of mosquito vector species. In Drosophila, Wolbachia mediates antiviral protection against a broad range of RNA viruses. This discovery pointed to a potential strategy to interfere with mosquito transmission of arboviruses by artificially infecting mosquitoes with Wolbachia. This review outlines research on the prevalence of Wolbachia in mosquito vector species and the impact of antiviral effects in both naturally and artificially Wolbachia-infected mosquitoes.

  4. Dissecting vectorial capacity for mosquito-borne viruses.

    PubMed

    Kramer, Laura D; Ciota, Alexander T

    2015-12-01

    The inter-relationship between mosquitoes and the viruses they transmit is complex. While previously understood barriers to infection and transmission remain valid, additional factors have been uncovered that suggest an 'arms race' between mosquito and virus. These include the mosquito microbiota and interplay between mosquito and viral genetics. Following an infectious blood meal, the mosquito mounts an immune and transcriptional response, leading to altered expression of multiple genes. These complex interactions, specific to vector and virus genotypes, combine with external influences, particularly temperature, to determine vector competence. The mosquito's response to the infecting agent may have consequences in terms of longevity, feeding behavior and/or fecundity. These factors, together with population density and the frequency of host contact determine vectorial capacity.

  5. What Is the Prevalence of Adult ADHD? Results of a Population Screen of 966 Adults

    ERIC Educational Resources Information Center

    Faraone, Stephen V.; Biederman, Joseph

    2005-01-01

    To provide a better estimate of the prevalence of ADHD in adulthood, the authors complete a telephone survey of 966 randomly selected adults. They compute two diagnoses from the survey data. Participants meeting "Diagnostic and Statistical Manual of Mental Disorders" (4th ed.) criteria for both childhood and adulthood are defined as narrow ADHD.…

  6. A novel video-tracking system to quantify the behaviour of nocturnal mosquitoes attacking human hosts in the field

    PubMed Central

    Abe, M.; Mashauri, F.; Martine, J.

    2016-01-01

    Many vectors of malaria and other infections spend most of their adult life within human homes, the environment where they bloodfeed and rest, and where control has been most successful. Yet, knowledge of peri-domestic mosquito behaviour is limited, particularly how mosquitoes find and attack human hosts or how insecticides impact on behaviour. This is partly because technology for tracking mosquitoes in their natural habitats, traditional dwellings in disease-endemic countries, has never been available. We describe a sensing device that enables observation and recording of nocturnal mosquitoes attacking humans with or without a bed net, in the laboratory and in rural Africa. The device addresses requirements for sub-millimetre resolution over a 2.0 × 1.2 × 2.0 m volume while using minimum irradiance. Data processing strategies to extract individual mosquito trajectories and algorithms to describe behaviour during host/net interactions are introduced. Results from UK laboratory and Tanzanian field tests showed that Culex quinquefasciatus activity was higher and focused on the bed net roof when a human host was present, in colonized and wild populations. Both C. quinquefasciatus and Anopheles gambiae exhibited similar behavioural modes, with average flight velocities varying by less than 10%. The system offers considerable potential for investigations in vector biology and many other fields. PMID:27075002

  7. A novel video-tracking system to quantify the behaviour of nocturnal mosquitoes attacking human hosts in the field.

    PubMed

    Angarita-Jaimes, N C; Parker, J E A; Abe, M; Mashauri, F; Martine, J; Towers, C E; McCall, P J; Towers, D P

    2016-04-01

    Many vectors of malaria and other infections spend most of their adult life within human homes, the environment where they bloodfeed and rest, and where control has been most successful. Yet, knowledge of peri-domestic mosquito behaviour is limited, particularly how mosquitoes find and attack human hosts or how insecticides impact on behaviour. This is partly because technology for tracking mosquitoes in their natural habitats, traditional dwellings in disease-endemic countries, has never been available. We describe a sensing device that enables observation and recording of nocturnal mosquitoes attacking humans with or without a bed net, in the laboratory and in rural Africa. The device addresses requirements for sub-millimetre resolution over a 2.0 × 1.2 × 2.0 m volume while using minimum irradiance. Data processing strategies to extract individual mosquito trajectories and algorithms to describe behaviour during host/net interactions are introduced. Results from UK laboratory and Tanzanian field tests showed that Culex quinquefasciatus activity was higher and focused on the bed net roof when a human host was present, in colonized and wild populations. Both C. quinquefasciatus and Anopheles gambiae exhibited similar behavioural modes, with average flight velocities varying by less than 10%. The system offers considerable potential for investigations in vector biology and many other fields.

  8. Stage-Structured Population Dynamics of AEDES AEGYPTI

    NASA Astrophysics Data System (ADS)

    Yusoff, Nuraini; Budin, Harun; Ismail, Salemah

    Aedes aegypti is the main vector in the transmission of dengue fever, a vector-borne disease affecting world population living in tropical and sub-tropical countries. Better understanding of the dynamics of its population growth will help in the efforts of controlling the spread of this disease. In looking at the population dynamics of Aedes aegypti, this paper explored the stage-structured modeling of the population growth of the mosquito using the matrix population model. The life cycle of the mosquito was divided into five stages: eggs, larvae, pupae, adult1 and adult2. Developmental rates were obtained for the average Malaysian temperature and these were used in constructing the transition matrix for the matrix model. The model, which was based only on temperature, projected that the population of Aedes aegypti will blow up with time, which is not realistic. For further work, other factors need to be taken into account to obtain a more realistic result.

  9. Detection of West Nile virus RNA in mosquitoes and identification of mosquito blood meals collected at alligator farms in Louisiana.

    PubMed

    Unlu, Isik; Kramer, Wayne L; Roy, Alma F; Foil, Lane D

    2010-07-01

    Since 2001, alligator farms in the United States have sustained substantial economic losses because of West Nile virus (WNV) outbreaks in American alligators (Alligator mississippiensis). Once an initial infection is introduced into captive alligators, WNV can spread among animals by contaminative transmission. Some outbreaks have been linked to feeding on infected meat or the introduction of infected hatchlings, but the initial source of WNV infection has been uncertain in other outbreaks. We conducted a study to identify species composition and presence of WNV in mosquito populations associated with alligator farms in Louisiana. A second objective of this study was to identify the origin of mosquito blood meals collected at commercial alligator farms. Mosquitoes were collected from 2004 to 2006, using Centers for Disease Control light traps, gravid traps, backpack aspirators, and resting boxes. We collected a total of 58,975 mosquitoes representing 24 species. WNV was detected in 41 pools of females from 11 mosquito species: Anopheles crucians, Anopheles quadrimaculatus, Coquillettidia perturbans, Culex coronator, Culex erraticus, Culex nigripalpus, Culex quinquefasciatus, Mansonia titillans, Aedes sollicitans, Psorophora columbiae, and Uranotaenia lowii. The blood meal origins of 213 field-collected mosquitoes were identified based on cytochrome B sequence identity. Alligator blood was detected in 21 mosquitoes representing six species of mosquitoes, including Cx. quinquefasciatus and Cx. nigripalpus. Our results showed that mosquitoes of species that are known to be competent vectors of WNV fed regularly on captive alligators. Therefore, mosquitoes probably are important in the role of transmission of WNV at alligator farms.

  10. Changes in local mosquito fauna following beaver (Castor canadensis) activity.

    PubMed

    Butts, W L

    1986-09-01

    A marked decrease in anthropophilic temporary water mosquito populations subsequent to impoundment of extensive areas of larval development by beavers is documented. Absence to date of development of other mosquito species in the permanent water thus established is noted and discussed relative to current characteristics of the site.

  11. High-frequency audiometric assessment of a young adult population.

    PubMed

    Green, D M; Kidd, G; Stevens, K N

    1987-02-01

    The hearing thresholds of 37 young adults (18-26 years) were measured at 13 frequencies (8, 9,10,...,20 kHz) using a newly developed high-frequency audiometer. All subjects were screened at 15 dB HL at the low audiometric frequencies, had tympanometry within normal limits, and had no history of significant hearing problems. The audiometer delivers sound from a driver unit to the ear canal through a lossy tube and earpiece providing a source impedance essentially equal to the characteristic impedance of the tube. A small microphone located within the earpiece is used to measure the response of the ear canal when an impulse is applied at the driver unit. From this response, a gain function is calculated relating the equivalent sound-pressure level of the source to the SPL at the medial end of the ear canal. For the subjects tested, this gain function showed a gradual increase from 2 to 12 dB over the frequency range. The standard deviation of the gain function was about 2.5 dB across subjects in the lower frequency region (8-14 kHz) and about 4 dB at the higher frequencies. Cross modes and poor fit of the earpiece to the ear canal prevented accurate calibration for some subjects at the highest frequencies. The average SPL at threshold was 23 dB at 8 kHz, 30 dB at 12 kHz, and 87 dB at 18 kHz. Despite the homogeneous nature of the sample, the younger subjects in the sample had reliably better thresholds than the older subjects. Repeated measurements of threshold over an interval as long as 1 month showed a standard deviation of 2.5 dB at the lower frequencies (8-14 kHz) and 4.5 dB at the higher frequencies.

  12. Multidimensional Clinical Phenotyping of an Adult Cystic Fibrosis Patient Population

    PubMed Central

    Conrad, Douglas J.; Bailey, Barbara A.

    2015-01-01

    Background Cystic Fibrosis (CF) is a multi-systemic disease resulting from mutations in the Cystic Fibrosis Transmembrane Regulator (CFTR) gene and has major manifestations in the sino-pulmonary, and gastro-intestinal tracts. Clinical phenotypes were generated using 26 common clinical variables to generate classes that overlapped quantiles of lung function and were based on multiple aspects of CF systemic disease. Methods The variables included age, gender, CFTR mutations, FEV1% predicted, FVC% predicted, height, weight, Brasfield chest xray score, pancreatic sufficiency status and clinical microbiology results. Complete datasets were compiled on 211 subjects. Phenotypes were identified using a proximity matrix generated by the unsupervised Random Forests algorithm and subsequent clustering by the Partitioning around Medoids (PAM) algorithm. The final phenotypic classes were then characterized and compared to a similar dataset obtained three years earlier. Findings Clinical phenotypes were identified using a clustering strategy that generated four and five phenotypes. Each strategy identified 1) a low lung health scores phenotype, 2) a younger, well-nourished, male-dominated class, 3) various high lung health score phenotypes that varied in terms of age, gender and nutritional status. This multidimensional clinical phenotyping strategy identified classes with expected microbiology results and low risk clinical phenotypes with pancreatic sufficiency. Interpretation This study demonstrated regional adult CF clinical phenotypes using non-parametric, continuous, ordinal and categorical data with a minimal amount of subjective data to identify clinically relevant phenotypes. These studies identified the relative stability of the phenotypes, demonstrated specific phenotypes consistent with published findings and identified others needing further study. PMID:25822311

  13. Exotic mosquito threats require strategic surveillance and response planning.

    PubMed

    Webb, Cameron E; Doggett, Stephen L

    2016-12-14

    Mosquito-borne diseases caused by endemic pathogens such as Ross River, Barmah Forest and Murray Valley encephalitis viruses are an annual concern in New South Wales (NSW), Australia. More than a dozen mosquito species have been implicated in the transmission of these pathogens, with each mosquito occupying a specialised ecological niche that influences their habitat associations, host feeding preferences and the environmental drivers of their abundance. The NSW Arbovirus Surveillance and Mosquito Monitoring Program provides an early warning system for potential outbreaks of mosquito-borne disease by tracking annual activity of these mosquitoes and their associated pathogens. Although the program will effectively track changes in local mosquito populations that may increase with a changing climate, urbanisation and wetland rehabilitation, it will be less effective with current surveillance methodologies at detecting or monitoring changes in exotic mosquito threats, where different surveillance strategies need to be used. Exotic container-inhabiting mosquitoes such as Aedes aegypti and Ae. albopictus pose a threat to NSW because they are nuisance-biting pests and vectors of pathogens such as dengue, chikungunya and Zika viruses. International movement of humans and their belongings have spread these mosquitoes to many regions of the world. In recent years, these two mosquitoes have been detected by the Australian Government Department of Agriculture and Water Resources at local airports and seaports. To target the detection of these exotic mosquitoes, new trapping technologies and networks of surveillance locations are required. Additionally, incursions of these mosquitoes into urban areas of the state will require strategic responses to minimise substantial public health and economic burdens to local communities.

  14. Mosquitoes and the environment in Nile Delta villages with previous rift valley fever activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Egypt is affected by serious human and animal mosquito-borne diseases such as Rift Valley fever (RVF). We investigated how potential RVF virus mosquito vector populations are affected by environmental conditions in the Nile Delta region of Egypt by collecting mosquitoes and environmental data from t...

  15. Composition of Anopheles coluzzii and Anopheles gambiae microbiota from larval to adult stages.

    PubMed

    Gimonneau, Geoffrey; Tchioffo, Majoline T; Abate, Luc; Boissière, Anne; Awono-Ambéné, Parfait H; Nsango, Sandrine E; Christen, Richard; Morlais, Isabelle

    2014-12-01

    During their immature life stages, malaria mosquitoes are exposed to a wide array of microbes and contaminants from the aquatic habitats. Although prior studies have suggested that environmental exposure shapes the microbial community structure in the adult mosquito, most reports have focused on laboratory-based experiments and on a single mosquito epithelium, the gut. In this study, we investigated the influence of the breeding site on the development of the Anopheles coluzzii and Anopheles gambiae microbiota in natural conditions. We characterized bacterial communities from aquatic habitats, at surface microlayer and subsurface water levels, to freshly emerge adult mosquitoes using multiplexed 16S rRNA gene pyrosequencing and we separately analyzed the microbiota associated with the different epithelia of adult individual, midguts, ovaries and salivary glands. We found that the distribution of bacterial communities in the aquatic habitats differed according to the depth of water collections. Inter-individual variation of bacterial composition was large in larvae guts but adult mosquitoes from a same breeding site shared quite similar microbiota. Although some differences in bacterial abundances were highlighted between the different epithelia of freshly emerged An. coluzzii and An. gambiae, an intriguing feature from our study is the particular similarity of the overall bacterial communities. Our results call for further investigations on the bacterial population dynamics in the different tissues to determine the distinctive characteristics of each microbiota during the mosquito lifespan and to identify specific interactions between certain key phyla or species and the insect life history traits.

  16. Susceptibility of field-collected mosquitoes in central New Jersey to organophosphates and a pyrethroid.

    PubMed

    Sun, Debin; Indelicato, Nick; Petersen, Jack; Williges, Eric; Unlu, Isik; Farajollahi, Ary

    2014-06-01

    Chemical insecticides are the primary means to control mosquitoes, and mosquito control programs must regularly monitor for resistance of mosquito vectors to commonly used insecticides to ensure the efficacy and sustainability of active ingredients. We performed insecticide resistance bioassays to test the susceptibility of field-collected mosquitoes in central New Jersey to 1 larvicide (temephos) and 2 adulticides (malathion and sumithrin). Larval susceptibility of Culex pipiens pipiens to temephos provided median concentration (LC50) and 95% lethal concentration (LC95) values of 1.108 microg/l and 2.02 microg/l, respectively. Bottle bioassays of adult Aedes albopictus showed that 100% mortality was achieved at 35-min exposure to sumithrin and at 40-min to malathion. Baseline values were obtained using both temephos and sumithrin. Our bioassays indicate satisfactory susceptibility to temephos and sumithrin in Ae. albopictus and Cx. p. pipiens field populations in central New Jersey. Despite constant field use, both products are still effective and can be used adequately for control of the test species. However, the susceptibility of target insects to various formulations should be closely monitored periodically to ensure continual efficacy.

  17. Use of carbon-13 as a population marker for Anopheles arabiensis in a sterile insect technique (SIT) context

    PubMed Central

    Hood-Nowotny, Rebecca; Mayr, Leo; Knols, Bart GJ

    2006-01-01

    Background Monitoring of sterile to wild insect ratios in field populations can be useful to follow the progress in genetic control programmes such as the Sterile Insect Technique (SIT). Of the numerous methods for marking insects most are not suitable for use in mass rearing and mass release. Suitable ones include dye marking, genetic marking and chemical marking. Methods The feasibility of using the stable isotope of carbon, 13C, as a potential chemical marker for Anopheles arabiensis was evaluated in the laboratory. Labeled-13C glucose was incorporated into the larval diet in a powder or liquid form. The contribution of adult sugar feeding to the total mosquito carbon pool and the metabolically active carbon pool was determined by tracing the decline of the enrichment of the adult male mosquito as it switched from a labeled larval diet to an unlabeled adult diet. This decline in the adult was monitored by destructive sampling of the whole mosquito and analyzed using isotope ratio mass spectrometry. Results A two-pool model was used to describe the decline of the 13C-enrichment of adult mosquitoes. The proportion of the total adult carbon pool derived from the adult sugar diet over the life span of mosquitoes was determined and the ratio of structural carbon, with a low turnover rate to metabolically active non-structural carbon was assessed. The uptake and turnover of sugar in the metabolically active fraction suggests that after 3 days >70% of the active fraction carbon is derived from sugar feeding (increasing to >90% by day 7), indicating the high resource demand of male mosquitoes. Conclusion It was possible to "fix" the isotopic label in adult An. arabiensis and to detect the label at an appropriate concentration up to 21 days post-emergence. The optimum labeling treatment would cost around 250 US$ per million mosquitoes. Stable isotope marking may thus aid research on the fate of released insects besides other population-based ecological studies. PMID

  18. Components of the metabolic syndrome differ between young and old adults in the US population.

    PubMed

    Sumner, Andrew D; Sardi, Gabriel L; Reed, James F

    2012-08-01

    Prevalence of the metabolic syndrome (MetS) is high in the United States and is associated with increased risk of cardiovascular disease and diabetes. The authors examined whether the prevalence of the MetS and its components differs across age groups. Data were analyzed from 4 National Health and Nutrition Examination Surveys between the years 1999 and 2006. Prevalence of MetS as defined by the Third Report of the Adult Treatment Panel criteria and prevalence of associated cardiac risk factors were determined in 41,474 participants aged 18 years and older without a history of cardiovascular disease (CVD). All estimates were weighted. Prevalence of MetS among asymptomatic adults without CVD was 20.5% and remained stable for the total population during survey periods. Prevalence of MetS increased with age: 6.6% in young adults (age 18-29 years) and 34.6% in older adults (70 and older). Components of MetS differed between young and old adults. Young adults had lower levels of high-density lipoprotein cholesterol, less glucose intolerance, and less hypertension. This study provides an estimate of MetS prevalence in asymptomatic adults in the United States during an 8-year period revealing that MetS affects a large number of Americans. Components of MetS differ between young and old adults and may have important implications in their clinical management.

  19. Periodontal status in an urban adult population in Sweden.

    PubMed

    Söder, P O; Jin, L J; Söder, B; Wikner, S

    1994-04-01

    The purpose was to describe the current periodontal status in a Swedish urban population aged 31-40 yr. 1681 individuals, 840 men and 841 women, participated in the study. 68.5% of the subjects had low amount of plaque, 82.8% low level of calculus and 28.9% healthy gingiva or mild gingivitis. 82.8% of the subjects had no pockets with probing depth (PD) > or = 5 mm. 4.9% of the subjects had one tooth with PD > or = 5 mm, 6.7% 2-5 teeth, 2.4% 6-9 teeth and 3.2% > or = 10 teeth with pockets. 55.8% of the subjects had no missing teeth, third molars excluded. 16.5% had one tooth missing, 23.8% 2-5 teeth, 2.7% 6-9 teeth and 1.2% > or = 10 teeth. 8.6% of the subjects had at least one front tooth missing, 28.7% one premolar and 24.1% one molar missing. Men had significantly higher scores than women for plaque (DI-S), calculus (CI-S), gingivitis (GI-M), and number and percent of remaining teeth with PD > or = 5 mm. Smokers had significantly higher scores than non-smokers for DI-S, CI-S, GI-M, number and percent of remaining teeth with PD > or = 5 mm, and number of missing teeth. The individuals who visited the dentist every year had better oral hygiene and gingival status than those who attended for > 3 yr. The multiple regression analysis showed that calculus (P = 0.0001) smoking (P = 0.001), and dental visits (P = 0.0284) were significantly correlated to the number of teeth with PD > or = 5 mm.

  20. Breeding durations as estimators of adult sex ratios and population size.

    PubMed

    Payne, Nicholas Leslie; Gillanders, Bronwyn May; Semmens, Jayson

    2011-02-01

    Adult sex ratios (ASRs) and population size are two of the most fundamental parameters in population biology, as they are the main determinants of genetic and demographic viability, and vulnerability of a population to stochastic events. Underpinning the application of population viability analysis for predicting the extinction risk of populations is the need to accurately estimate parameters that determine the viability of populations (i.e. the ASR and population size). Here we demonstrate that a lack of temporal information can confound estimation of both parameters. Using acoustic telemetry, we compared differences in breeding durations of both sexes for a giant Australian cuttlefish Sepia apama breeding aggregation to the strongly male-biased operational sex ratio (4:1), in order to estimate the population ASR. The ratio of breeding durations between sexes was equal to the operational sex ratio, suggesting that the ASR is not strongly male-biased, but balanced. Furthermore, the short residence times of individuals at the breeding aggregation suggests that previous density-based abundance estimates have significantly underestimated population size. With the current wide application of population viability analysis for predicting the extinction risk of populations, tools to improve the accuracy of such predictions are vital. Here we provide a new approach to estimating the fundamental ASR parameter, and call for temporal considerations when estimating population size.

  1. Associations among depressive symptoms, childhood abuse, neuroticism, and adult stressful life events in the general adult population

    PubMed Central

    Ono, Kotaro; Takaesu, Yoshikazu; Nakai, Yukiei; Shimura, Akiyoshi; Ono, Yasuyuki; Murakoshi, Akiko; Matsumoto, Yasunori; Tanabe, Hajime; Kusumi, Ichiro; Inoue, Takeshi

    2017-01-01

    Background Recent studies have suggested that the interactions among several factors affect the onset, progression, and prognosis of major depressive disorder. This study investigated how childhood abuse, neuroticism, and adult stressful life events interact with one another and affect depressive symptoms in the general adult population. Subjects and methods A total of 413 participants from the nonclinical general adult population completed the Patient Health Questionnaire-9, the Child Abuse and Trauma Scale, the neuroticism subscale of the shortened Eysenck Personality Questionnaire – Revised, and the Life Experiences Survey, which are self-report scales. Structural equation modeling (Mplus version 7.3) and single and multiple regressions were used to analyze the data. Results Childhood abuse, neuroticism, and negative evaluation of life events increased the severity of the depressive symptoms directly. Childhood abuse also indirectly increased the negative appraisal of life events and the severity of the depressive symptoms through enhanced neuroticism in the structural equation modeling. Limitations There was recall bias in this study. The causal relationship was not clear because this study was conducted using a cross-sectional design. Conclusion This study suggested that neuroticism is the mediating factor for the two effects of childhood abuse on adulthood depressive symptoms and negative evaluation of life events. Childhood abuse directly and indirectly predicted the severity of depressive symptoms. PMID:28243100

  2. Population Dynamics of Aedes aegypti and Dengue as Influenced by Weather and Human Behavior in San Juan, Puerto Rico

    PubMed Central

    Barrera, Roberto; Amador, Manuel; MacKay, Andrew J.

    2011-01-01

    Previous studies on the influence of weather on Aedes aegypti dynamics in Puerto Rico suggested that rainfall was a significant driver of immature mosquito populations and dengue incidence, but mostly in the drier areas of the island. We conducted a longitudinal study of Ae. aegypti in two neighborhoods of the metropolitan area of San Juan city, Puerto Rico where rainfall is more uniformly distributed throughout the year. We assessed the impacts of rainfall, temperature, and human activities on the temporal dynamics of adult Ae. aegypti and oviposition. Changes in adult mosquitoes were monitored with BG-Sentinel traps and oviposition activity with CDC enhanced ovitraps. Pupal surveys were conducted during the drier and wetter parts of the year in both neighborhoods to determine the contribution of humans and rains to mosquito production. Mosquito dynamics in each neighborhood was compared with dengue incidence in their respective municipalities during the study. Our results showed that: 1. Most pupae were produced in containers managed by people, which explains the prevalence of adult mosquitoes at times when rainfall was scant; 2. Water meters were documented for the first time as productive habitats for Ae. aegypti; 3. Even though Puerto Rico has a reliable supply of tap water and an active tire recycling program, water storage containers and discarded tires were important mosquito producers; 4. Peaks in mosquito density preceded maximum dengue incidence; and 5. Ae. aegypti dynamics were driven by weather and human activity and oviposition was significantly correlated with dengue incidence. PMID:22206021

  3. Population dynamics of Aedes aegypti and dengue as influenced by weather and human behavior in San Juan, Puerto Rico.

    PubMed

    Barrera, Roberto; Amador, Manuel; MacKay, Andrew J

    2011-12-01

    Previous studies on the influence of weather on Aedes aegypti dynamics in Puerto Rico suggested that rainfall was a significant driver of immature mosquito populations and dengue incidence, but mostly in the drier areas of the island. We conducted a longitudinal study of Ae. aegypti in two neighborhoods of the metropolitan area of San Juan city, Puerto Rico where rainfall is more uniformly distributed throughout the year. We assessed the impacts of rainfall, temperature, and human activities on the temporal dynamics of adult Ae. aegypti and oviposition. Changes in adult mosquitoes were monitored with BG-Sentinel traps and oviposition activity with CDC enhanced ovitraps. Pupal surveys were conducted during the drier and wetter parts of the year in both neighborhoods to determine the contribution of humans and rains to mosquito production. Mosquito dynamics in each neighborhood was compared with dengue incidence in their respective municipalities during the study. Our results showed that: 1. Most pupae were produced in containers managed by people, which explains the prevalence of adult mosquitoes at times when rainfall was scant; 2. Water meters were documented for the first time as productive habitats for Ae. aegypti; 3. Even though Puerto Rico has a reliable supply of tap water and an active tire recycling program, water storage containers and discarded tires were important mosquito producers; 4. Peaks in mosquito density preceded maximum dengue incidence; and 5. Ae. aegypti dynamics were driven by weather and human activity and oviposition was significantly correlated with dengue incidence.

  4. Mosquito Immunity against Arboviruses

    PubMed Central

    Sim, Shuzhen; Jupatanakul, Natapong; Dimopoulos, George

    2014-01-01

    Arthropod-borne viruses (arboviruses) pose a significant threat to global health, causing human disease with increasing geographic range and severity. The recent availability of the genome sequences of medically important mosquito species has kick-started investigations into the molecular basis of how mosquito vectors control arbovirus infection. Here, we discuss recent findings concerning the role of the mosquito immune system in antiviral defense, interactions between arboviruses and fundamental cellular processes such as apoptosis and autophagy, and arboviral suppression of mosquito defense mechanisms. This knowledge provides insights into co-evolutionary processes between vector and virus and also lays the groundwork for the development of novel arbovirus control strategies that target the mosquito vector. PMID:25415198

  5. Influence of resource levels, organic compounds, and laboratory colonization on interspecific competition between the Asian tiger mosquito (Aedes albopictus) and the southern house mosquito (Culex quinquefasciatus)

    PubMed Central

    Allgood, David W.; Yee, Donald A.

    2013-01-01

    The mosquitoes Aedes albopictus (Skuse) and Culex quinquefasciatus (Say) (Diptera:Culicidae) are common inhabitants of tyres and other artificial containers, which constitute important peridomestic mosquito breeding habitats. We tested the hypotheses that interspecific resource competition between the larvae of these species is asymmetrical, that the concentration of chemicals associated with decomposing detritus affects their competitive outcome, and that wild and colonized strains of Cx. quinquefasciatus are affected differently by competition with Ae. albopictus. We conducted two laboratory competition experiments wherein we measured survivorship and estimated population growth (λ’) of both species under multiple mixed-species densities. Under varying resource levels, competition was asymmetrical with Ae. albopictus causing competitive reductions or exclusions of Cx. quinquefasciatus under limited resources. In a second experiment, which used both wild and colonized strains of Cx. quinquefasciatus, organic chemical compounds associated with decomposing detritus did not affect the competitive outcome. The colonized strain of Cx. quinquefasciatus had greater survivorship, adult mass, and faster development times than the wild strain, but both strains were similarly affected by competition with Ae. albopictus. Competition between these species may have important consequences for vector population dynamics, especially in areas where tyres and artificial containers constitute the majority of mosquito breeding habitats. PMID:24444185

  6. Population-Based Surveillance for Invasive Pneumococcal Disease in Homeless Adults in Toronto

    PubMed Central

    Plevneshi, Agron; Svoboda, Tomislav; Armstrong, Irene; Tyrrell, Gregory J.; Miranda, Anna; Green, Karen; Low, Donald; McGeer, Allison

    2009-01-01

    Background Identification of high-risk populations for serious infection due to S. pneumoniae will permit appropriately targeted prevention programs. Methods We conducted prospective, population-based surveillance for invasive pneumococcal disease and laboratory confirmed pneumococcal pneumonia in homeless adults in Toronto, a Canadian city with a total population of 2.5 M, from January 1, 2002 to December 31, 2006. Results We identified 69 cases of invasive pneumococcal disease and 27 cases of laboratory confirmed pneumococcal pneumonia in an estimated population of 5050 homeless adults. The incidence of invasive pneumococcal disease in homeless adults was 273 infections per 100,000 persons per year, compared to 9 per 100,000 persons per year in the general adult population. Homeless persons with invasive pneumococcal disease were younger than other adults (median age 46 years vs 67 years, P<.001), and more likely than other adults to be smokers (95% vs. 31%, P<.001), to abuse alcohol (62% vs 15%, P<.001), and to use intravenous drugs (42% vs 4%, P<.001). Relative to age matched controls, they were more likely to have underlying lung disease (12/69, 17% vs 17/272, 6%, P = .006), but not more likely to be HIV infected (17/69, 25% vs 58/282, 21%, P = .73). The proportion of patients with recurrent disease was five fold higher for homeless than other adults (7/58, 12% vs. 24/943, 2.5%, P<.001). In homeless adults, 28 (32%) of pneumococcal isolates were of serotypes included in the 7-valent conjugate vaccine, 42 (48%) of serotypes included in the 13-valent conjugate vaccine, and 72 (83%) of serotypes included in the 23-valent polysaccharide vaccine. Although no outbreaks of disease were identified in shelters, there was evidence of clustering of serotypes suggestive of transmission of pathogenic strains within the homeless population. Conclusions Homeless persons are at high risk of serious pneumococcal infection. Vaccination, physical structure changes or

  7. Eysenck Personality Inventory: A Normative Study on an Adult Industrial Population.

    ERIC Educational Resources Information Center

    Hester, Reid K.; Brown, William R.

    1980-01-01

    Developed norms for an adult industrial population for the Eysenck Personality Inventory. An analysis of scale scores by age, sex, marital status, and occupational category revealed significant differences in extraversion scale scores by age and sex. Norm tables are presented by sex. (Author)

  8. The Contributions of Phonological and Morphological Awareness to Literacy Skills in the Adult Basic Education Population

    ERIC Educational Resources Information Center

    Fracasso, Lucille E.; Bangs, Kathryn; Binder, Katherine S.

    2016-01-01

    The Adult Basic Education (ABE) population consists of a wide range of abilities with needs that may be unique to this set of learners. The purpose of this study was to better understand the relative contributions of phonological decoding and morphological awareness to spelling, vocabulary, and comprehension across a sample of ABE students. In…

  9. "Subtypes" in the Presentation of Autistic Traits in the General Adult Population

    ERIC Educational Resources Information Center

    Palmer, Colin J.; Paton, Bryan; Enticott, Peter G.; Hohwy, Jakob

    2015-01-01

    The present study examined the presentation of autistic traits in a large adult population sample (n = 2,343). Cluster analysis indicated two subgroups with clearly distinguishable trait profiles. One group (n = 1,059) reported greater social difficulties and lower detail orientation, while the second group (n = 1,284) reported lesser social…

  10. A Meta-Analysis of Dunn and Dunn Model Correlational Research with Adult Populations

    ERIC Educational Resources Information Center

    Mangino, Christine

    2004-01-01

    The purpose of this investigation was to conduct a quantitative synthesis of correlational research that focused on the Dunn and Dunn Learning-Style Model and was concerned with adult populations. A total of 8,661 participants from the 47 original investigations provided 386 individual effect sizes for this meta-analysis. The mean effect size was…

  11. Meeting the Needs of Older Adult Refugee Populations With Home Health Services.

    PubMed

    Miner, Sarah M; Liebel, Dianne; Wilde, Mary H; Carroll, Jennifer K; Zicari, Elizabeth; Chalupa, Stephanie

    2015-12-27

    The United States resettles close to 70,000 refugees each year more than any other country in the world. Adult refugees are at risk for negative health outcomes and inefficient health resource use, and meeting the multiple health needs of this vulnerable population is a challenge. The purpose of this study was to assess the impact of a home health care (HHC) pilot project on meeting the needs of older adult refugee patients. A retrospective chart review of 40 refugee adult patients who participated in an HHC pilot was done to analyze their health outcomes using OASIS-C data. Participants' pain level, anxiety level, medication management, and activities of daily living management all significantly improved over the course of their HHC episode. Results of this study indicate that HHC has great potential to improve the health of vulnerable refugee populations and assist the families involved in their care.

  12. Occurrence and Spread of the Invasive Asian Bush Mosquito Aedes japonicus japonicus (Diptera: Culicidae) in West and North Germany since Detection in 2012 and 2013, Respectively.

    PubMed

    Kampen, Helge; Kuhlisch, Cornelius; Fröhlich, Andreas; Scheuch, Dorothee E; Walther, Doreen

    2016-01-01

    The invasive Asian bush mosquito Aedes japonicus japonicus was first recognised as established in Germany in 2008. In addition to the first known and quickly expanding population in the southwestern part of the country, three separate populations were discovered in West, North and southeastern Germany in 2012, 2013 and 2015, respectively, by means of the 'Mueckenatlas', a German instrument of passive mosquito surveillance. Since the first findings of mosquito specimens in West and North Germany, these regions were checked annually for continuing colonisation and spread of the species. Both affected areas were covered by a virtual 10x10km2 grid pattern in the cells of which cemeteries were screened for immature stages of the mosquito. The cells were considered populated as soon as larvae or pupae were detected, whereas they were classified as negative when no mosquito stages were found in the cemeteries of at least three different towns or villages. Presence was also recorded when Ae. j. japonicus adults were submitted to the 'Mueckenatlas' from the respective cell or when there was evidence of local occurrence in localities other than cemeteries. Based on this approach, a significant expansion of the populated area was documented in West Germany since the first detection of Ae. j. japonicus in 2012 (increase in positive grid cells by more than 400%), while the North German population appears not to be expanding so far (reduction of positive grid cells by ca. 30% since 2013). As Ae. j. japonicus finds suitable climatic and ecological conditions in Germany, the differential expansion of the two populations might be attributed to the West German population being older and thus more firmly established than the closely related but younger North German population that might still be in its founder phase. However, geographic spread of all German populations in the future is anticipated. Continuous surveillance is recommended, as Ae. j. japonicus is a competent vector of

  13. Occurrence and Spread of the Invasive Asian Bush Mosquito Aedes japonicus japonicus (Diptera: Culicidae) in West and North Germany since Detection in 2012 and 2013, Respectively

    PubMed Central

    Kampen, Helge; Kuhlisch, Cornelius; Fröhlich, Andreas; Scheuch, Dorothee E.; Walther, Doreen

    2016-01-01

    The invasive Asian bush mosquito Aedes japonicus japonicus was first recognised as established in Germany in 2008. In addition to the first known and quickly expanding population in the southwestern part of the country, three separate populations were discovered in West, North and southeastern Germany in 2012, 2013 and 2015, respectively, by means of the ‘Mueckenatlas’, a German instrument of passive mosquito surveillance. Since the first findings of mosquito specimens in West and North Germany, these regions were checked annually for continuing colonisation and spread of the species. Both affected areas were covered by a virtual 10x10km2 grid pattern in the cells of which cemeteries were screened for immature stages of the mosquito. The cells were considered populated as soon as larvae or pupae were detected, whereas they were classified as negative when no mosquito stages were found in the cemeteries of at least three different towns or villages. Presence was also recorded when Ae. j. japonicus adults were submitted to the ‘Mueckenatlas’ from the respective cell or when there was evidence of local occurrence in localities other than cemeteries. Based on this approach, a significant expansion of the populated area was documented in West Germany since the first detection of Ae. j. japonicus in 2012 (increase in positive grid cells by more than 400%), while the North German population appears not to be expanding so far (reduction of positive grid cells by ca. 30% since 2013). As Ae. j. japonicus finds suitable climatic and ecological conditions in Germany, the differential expansion of the two populations might be attributed to the West German population being older and thus more firmly established than the closely related but younger North German population that might still be in its founder phase. However, geographic spread of all German populations in the future is anticipated. Continuous surveillance is recommended, as Ae. j. japonicus is a competent

  14. Diversity of riceland mosquitoes and factors affecting their occurrence and distribution in Mwea, Kenya.

    PubMed

    Muturi, Ephantus J; Shililu, Josephat I; Jacob, Benjamin G; Mwangangi, Joseph M; Mbogo, Charles M; Githure, John I; Novak, Robert J

    2008-09-01

    Knowledge of mosquito species diversity, occurrence, and distribution is an essential component of vector ecology and a guiding principle to formulation and implementation of integrated vector management programs. A 12-month entomological survey was conducted to determine the diversity of riceland mosquitoes and factors affecting their occurrence and distribution at 3 sites targeted for malaria vector control in Mwea, Kenya. Adult mosquitoes were sampled indoors by pyrethrum spray catch and outdoors by the Centers for Disease Control and Prevention light traps. Mosquitoes were then morphologically identified to species using taxonomic keys. The characteristics of houses sampled for indoor resting mosquitoes, including number of people sleeping in each house the night preceding collection, presence of bed nets, location of the house, size of eaves, wall type, presence of cattle and distance of the house to the cowshed, and proximity to larval habitats, were recorded. Of the 191,378 mosquitoes collected, 95% were identified morphologically to species and comprised 25 species from 5 genera. Common species included Anopheles arabiensis (53.5%), Culex quinquefasciatus (35.5%), An. pharoensis (4.7%), An. coustani (2.5%), and An. funestus (1.6%). Shannon's species diversity and evenness indices did not differ significantly among the 3 study sites. There was a marked house-to-house variation in the average number of mosquitoes captured. The number of people sleeping in the house the night preceding collection, size of eaves, distance to the cowshed, and the nearest larval habitat were significant predictors of occurrence of either or both An. arabiensis and Cx. quinquefasciatus. The peak abundance of An. arabiensis coincided with land preparation and the first few weeks after transplanting of rice seedlings, and that of Cx. quinquefasciatus coincided with land preparation, late stage of rice development, and short rains. After transplanting of rice seedlings, the

  15. The influence of house construction on the indoor abundance of mosquitoes.

    PubMed

    Howell, Paul I; Chadee, Dave D

    2007-06-01

    This study examined the potential effects of different house construction features on the indoor abundance of culicine mosquitoes in Trinidad (TT) and the Dominican Republic (DR) using xenomonitoring surveys. To assess these effects, a survey was taken of different homes in both countries alongside concurrent indoor resting mosquito collections to determine which features may be correlated with a greater abundance. Between June 2002 and April 2003 data were collected from 104 homes in TT and 121 homes in the DR. In TT, 61 (58.65%) of the homes were located in urban areas and 43 (41.35%) were located in rural villages, whereas in the DR 40 (33.06%) were located in rural areas, and 81 (66.94%) in the urban area. Overall, a total of 1,630 mosquitoes were collected in TT, of which 77% were Culex quinquefasciatus, whereas 459 mosquitoes were collected from the DR, of which 46% were Cx. quinquefasciatus. It was found that in TT and the DR the mean number of Cx. quinquefasciatus mosquitoes was greater in cement homes than in either wood or other poorer quality homes (TT cement 17.43, others 14.43; DR cement 4.24, others 3.41). In TT it was found that homes that had painted interiors were significantly more likely to have a high abundance of mosquitoes resting indoors compared to homes without painted interiors (OR 2.90, CI 1.09-8.72). Likewise, having a painted exterior was not significant, but only slightly so, in TT as having a detrimental effect (OR 2.14, CI 0.89-6.67). Similarly, having a painted interior or exterior was also found to be a predictor of a high abundance of indoor resting mosquitoes in the DR (interior OR 3.13, CI 1.41-6.92; exterior OR 1.97, CI .91-4.26). Reduced adult abundance in TT was correlated with homes being built on stilts, with more than four people sleeping in the home, and having a painted interior. In the DR, reductions were correlated with homes where residents slept under a bed net and with people who lived in a rural location. Changes

  16. New State Records of Mosquitoes for Colorado.

    PubMed

    Rose, Dominic A; Kondratieff, B C; Weissmann, M J

    2015-06-01

    The 1967 treatment of the Mosquitoes of Colorado by Harmston and Lawson and subsequent publications have recorded 46 culicid species from Colorado. As part of a study to create an updated synopsis of the mosquitoes of Colorado, adult trapping at numerous localities was conducted in Colorado during the summers of 2013 and 2014. This review also included an examination of mosquito specimens in various relevant museum collections. Aedes (Ochlerotatus) niphadopsis and Ae. (Och.) spencerii spencerii were collected during the 2013 and 2014 field seasons. Records for Ae. (Och.) canadensis canadensis, Ae. (Stegomyia) aegypti, and Uranotaenia (Pseudoficalbia) anhydor syntheta were obtained from examination of museum specimens. These species constitute new state records for Colorado, with 51 species now known from the state.

  17. Radiation biology of mosquitoes

    PubMed Central

    Helinski, Michelle EH; Parker, Andrew G; Knols, Bart GJ

    2009-01-01

    There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT) to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal stage was irradiated due to ease of handling compared to the adult stage. The dose-response curve between the induced sterility and log (dose) was shown to be sigmoid, and there was a marked species difference in radiation sensitivity. Mating competitiveness studies have generally been performed under laboratory conditions. The competitiveness of males irradiated at high doses was relatively poor, but with increasing ratios of sterile males, egg hatch could be lowered effectively. Males irradiated as pupae had a lower competitiveness compared to males irradiated as adults, but the use of partially-sterilizing doses has not been studied extensively. Methods to reduce somatic damage during the irradiation process as well as the use of other agents or techniques to induce sterility are discussed. It is concluded that the optimal radiation dose chosen for insects that are to be released during an SIT programme should ensure a balance between induced sterility of males and their field competitiveness, with competitiveness being determined under (semi-) field conditions. Self-contained 60Co research irradiators remain the most practical irradiators but these are likely to be replaced in the future by a new generation of high output X ray irradiators. PMID:19917076

  18. Long-term sedative use among community-dwelling adults: a population-based analysis

    PubMed Central

    Weymann, Deirdre; Gladstone, Emilie J.; Smolina, Kate; Morgan, Steven G.

    2017-01-01

    Background: Chronic use of benzodiazepines and benzodiazepine-like sedatives (z-drugs) presents substantial risks to people of all ages. We sought to assess trends in long-term sedative use among community-dwelling adults in British Columbia. Methods: Using population-based linked administrative databases, we examined longitudinal trends in age-standardized rates of sedative use among different age groups of community-dwelling adults (age ≥ 18 yr), from 2004 to 2013. For each calendar year, we classified adults as nonusers, short-term users, or long-term users of sedatives based on their patterns of sedative dispensation. For calendar year 2013, we applied cross-sectional analysis and estimated logistic regression models to identify health and socioeconomic risk factors associated with long-term sedative use. Results: More than half (53.4%) of long-term users of sedatives in British Columbia are between ages 18 and 64 years (young and middle-aged adults). From 2004 to 2013, long-term sedative use remained stable among adults more than 65 years of age (older adults) and increased slightly among young and middle-aged adults. Although the use of benzodiazepines decreased during the study period, the trend was offset by equal or greater increases in long-term use of z-drugs. Being an older adult, sick, poor and single were associated with increased odds of long-term sedative use. Interpretation: Despite efforts to stem such patterns of medication use, long-term use of sedatives increased in British Columbia between 2004 and 2013. This increase was driven largely by increased use among middle-aged adults. Future deprescribing efforts that target adults of all ages may help curb this trend.

  19. Chemicals isolated from Justicia adhatoda Linn reduce fitness of the mosquito, Aedes aegypti L.

    PubMed

    Thanigaivel, Annamalai; Senthil-Nathan, Sengottayan; Vasantha-Srinivasan, Prabhakaran; Edwin, Edward-Sam; Ponsankar, Athirstam; Selin-Rani, Selvaraj; Pradeepa, Venkatraman; Chellappandian, Muthiah; Kalaivani, Kandaswamy; Abdel-Megeed, Ahmed; Narayanan, Raman; Murugan, Kadarkarai

    2017-04-01

    Extracts from Justicia adhatoda L. (Acanthaceae) strongly reduced the fitness of the mosquito, Aedes aegypti Linn. The methanolic extracts inhibited several enzymes responsible for protecting insects from oxidative and other damage, including glutathione-S-transferase, superoxide dismutase, cytochrome P450, and α- and β-esterases. They increased repellency (maximum repellency at 100 ppm) in host-seeking adult females using the "arm-in cage assay." Histopathological examination showed the extracts led to serious midgut cell damage. Justicia adhatoda extracts led to reduced fecundity and oviposition of gravid females compared to controls. The extracts led to substantially reduced A. aegypti survival. We infer that the extracts have potential to reduce pathogen transmission by suppressing population growth of A. aegypti, and possibly other mosquito species.

  20. Status of Aedes japonicus in the Metropolitan Mosquito Control District, Minnesota.

    PubMed

    Johnson, Kirk A; Brogren, Sandra J; Crane, Diann M; Lamere, Carey A

    2010-09-01

    ABSTRACT. The Asian exotic mosquito Aedes japonicus was 1st collected in Minnesota in 2007 and was well established in parts of the Metropolitan Mosquito Control District (MMCD) by 2008. Surveillance strategies were devised for 2009 to track the expansion of its range through MMCD and to direct control efforts. Sampling of larvae from container and tire habitats was the primary method used to document Ae. japonicus presence, but larvae were found in other habitats as well. Adult Ae. japonicus were collected by vacuum aspirator, gravid trap, and New Jersey trap but not by CO2-baited Centers for Disease Control and Prevention light trap. Aedes japonicus were collected from each of the 7 counties surveyed; in 5 of the counties for the 1st time in 2009. Preliminary findings suggest that a control strategy involving intensive source reduction can reduce Ae. japonicus populations.

  1. Natural and engineered mosquito immunity.

    PubMed

    Alphey, Luke

    2009-01-01

    A recent paper in BMC Microbiology shows how suppression of mosquito innate immunity against a virus that the mosquito can normally tolerate increases mosquito mortality. This is just one of several approaches that may soon bring genetics-based mosquito control methods from the laboratory into the field.

  2. Vorticella sp: Prospective Mosquito Biocontrol Agent

    PubMed Central

    Patil, Chandrashekhar Devidas; Narkhede, Chandrakant Prakash; Suryawanshi, Rahul Khushal; Patil, Satish Vitthal

    2016-01-01

    Background: Considering the disadvantages of chemical insecticides, we aimed to evaluate Vorticella parasites for control of mosquito larvae of Anopheles stephensi and Aedes aegypti at different larval stages. Methods: Vorticella sp infected mosquito larvae were crushed in the 0.85% saline and homogenized well to get Vorticella in suspension. The effects of Vorticella sp infections on larval development were investigated by inoculating protozoan on different larval instars of An. stephensi and Ae. aegypti and observed under light microscope. Lethal time of the Vorticella infected larvae at different stages was calculated. Results: First and 2nd larval instars of both An. stephensi and Ae. aegypti did not show signs of infection by Vorticella sp., whereas 3rd instars of An. stephensi showed more Vorticella infection than those of Ae. aegypti. However, 4th larval instars of both mosquitoes were heavily infected with Vorticella parasite which was responsible for sluggish movements of larvae and eventually death. Moreover, parasites (Vorticella spp) were responsible for more than 90% reduction in adult emergence for both infected An. stephensi and Ae. aegypti. Conclusion: This study provides insights for mosquito larvicidal action of surface parasite Vorticella on different larval stages of An. stephensi and Ae. Aegypti. It could be suggested as a potential candidate in mosquito biocontrol programs. PMID:28032113

  3. Body Mass Index in Adults with Intellectual Disability: Distribution, Associations and Service Implications--A Population-Based Prevalence Study

    ERIC Educational Resources Information Center

    Bhaumik, S.; Watson, J. M.; Thorp, C. F.; Tyrer, F.; McGrother, C. W.

    2008-01-01

    Background: Previous studies of weight problems in adults with intellectual disability (ID) have generally been small or selective and given conflicting results. The objectives of our large-scale study were to identify inequalities in weight problems between adults with ID and the general adult population, and to investigate factors associated…

  4. Commensal Viruses of Mosquitoes: Host Restriction, Transmission, and Interaction with Arboviral Pathogens

    PubMed Central

    Hall, Roy A.; Bielefeldt-Ohmann, Helle; McLean, Breeanna J.; O’Brien, Caitlin A.; Colmant, Agathe M.G.; Piyasena, Thisun B.H.; Harrison, Jessica J.; Newton, Natalee D.; Barnard, Ross T.; Prow, Natalie A.; Deerain, Joshua M.; Mah, Marcus G.K.Y.; Hobson-Peters, Jody

    2016-01-01

    Recent advances in virus detection strategies and deep sequencing technologies have enabled the identification of a multitude of new viruses that persistently infect mosquitoes but do not infect vertebrates. These are usually referred to as insect-specific viruses (ISVs). These novel viruses have generated considerable interest in their modes of transmission, persistence in mosquito populations, the mechanisms that restrict their host range to mosquitoes, and their interactions with pathogens transmissible by the same mosquito. In this article, we discuss studies in our laboratory and others that demonstrate that many ISVs are efficiently transmitted directly from the female mosquito to their progeny via infected eggs, and, moreover, that persistent infection of mosquito cell cultures or whole mosquitoes with ISVs can restrict subsequent infection, replication, and transmission of some mosquito-borne viral pathogens. This suggests that some ISVs may act as natural regulators of arboviral transmission. We also discuss viral and host factors that may be responsible for their host restriction. PMID:28096646

  5. Normative data and discriminant validity of Rey's Verbal Learning Test for the Greek adult population.

    PubMed

    Messinis, Lambros; Tsakona, Ioanna; Malefaki, Sonia; Papathanasopoulos, Panagiotis

    2007-08-01

    The present study sought to establish normative and discriminant validity data for Rey's Auditory Verbal Learning Test [Rey, A. (1964). L 'examen clinique en psychologie [Clinical tests in psychology]. Paris: Presses Universitaires de France; Schmidt, M. (1996). Rey auditory verbal learning test: A handbook. Los Angeles, CA: Western Psychological Services] using newly adapted learning lists for the Greek adult population. Applying the procedure suggested by Geffen et al. [Geffen, G., Moar, K. J., O'Hanlon, A. P., Clark, C. R., & Geffen, L. N. (1990). Performance measures of 16-86-year-old males and females on the auditory verbal learning test. The Clinical Neuropsychologist, 4, 45-63] we administered the test to 205 healthy participants, aged 18-78 years and two adult patient groups (long-term cannabis users and HIV symptomatic patients). Stepwise linear regression analyses showed that the variables age, education and gender contributed significantly to most trials of the RAVLT. Performance decreased in an age-dependent manner from young adulthood. Women, young adults and higher educated participants outperformed men, older adults and less educated individuals. The test appears to discriminate adequately between the performance of long-term heavy cannabis users and HIV seropositive symptomatic patients and matched healthy controls, as both patient groups performed more poorly than their respective control group. Normative data stratified by age, gender and education for the Greek adult population is presented for use in research and clinical settings.

  6. The influence of diet on the use of near-infrared spectroscopy to determine the age of female Aedes aegypti mosquitoes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interventions targeting adult mosquitoes are used to combat transmission of vector-borne diseases, including dengue. Without available vaccines, targeting the primary vector, Aedes aegypti, is essential to prevent transmission. Older mosquitoes (>/='7 days) are of greatest epidemiological significan...

  7. Community Ecology of Container Mosquitoes (Diptera: Culicidae) in Virginia Following Invasion by Aedes japonicus

    PubMed Central

    ARMISTEAD, JENNIFER S.; NISHIMURA, NAOYA; ARIAS, JORGE R.; LOUNIBOS, L. PHILIP

    2012-01-01

    The success of an invasive species in a new region depends on its interactions with ecologically similar resident species. Invasions by disease vector mosquitoes are important as they may have ecological and epidemiological consequences. Potential interactions of a recent invasive mosquito, Aedes japonicus Theobald, with resident species in Virginia were evaluated by sampling larvae from containers and trapping adults. Distinct species compositions were observed for artificial containers and rock pools, with Ae. albopictus most abundant in the former and Ae. japonicus in the latter. However, these two species were found to co-occur in 21.2% of containers sampled. Among the six mosquito species most common in containers from May through September, 2006, only interspecific associations of Ae.japonicus with Aedesalbopictus(Skuse) and Aedestriseriatus(Say) were significant, and both were negative. In addition to differences in habitat preference, mean crowding estimates suggest that interspecific repulsion may contribute to the significant negative associations observed between these species. High relative abundances of late instars and pupae of Ae. japonicus seem to provide this species with a mechanism of evading competition with Ae. albopictus, facilitating their coexistence in artificial containers. Although annual fluctuations were observed, trends in adult populations over a 6-yr period provide no evidence of declines. In summary, this survey of diverse container types and all life stages provided only limited evidence for competitive displacements or reductions of resident container species by Ae. japonicus, as observed elsewhere in its invasive range. PMID:23270159

  8. Modeling dynamics of culex pipiens complex populations and assessing abatement strategies for West Nile Virus.

    PubMed

    Pawelek, Kasia A; Niehaus, Patrick; Salmeron, Cristian; Hager, Elizabeth J; Hunt, Gregg J

    2014-01-01

    The primary mosquito species associated with underground stormwater systems in the United States are the Culex pipiens complex species. This group represents important vectors of West Nile virus (WNV) throughout regions of the continental U.S. In this study, we designed a mathematical model and compared it with surveillance data for the Cx. pipiens complex collected in Beaufort County, South Carolina. Based on the best fit of the model to the data, we estimated parameters associated with the effectiveness of public health insecticide (adulticide) treatments (primarily pyrethrin products) as well as the birth, maturation, and death rates of immature and adult Cx. pipiens complex mosquitoes. We used these estimates for modeling the spread of WNV to obtain more reliable disease outbreak predictions and performed numerical simulations to test various mosquito abatement strategies. We demonstrated that insecticide treatments produced significant reductions in the Cx. pipiens complex populations. However, abatement efforts were effective for approximately one day and the vector mosquitoes rebounded until the next treatment. These results suggest that frequent insecticide applications are necessary to control these mosquitoes. We derived the basic reproductive number (ℜ0) to predict the conditions under which disease outbreaks are likely to occur and to evaluate mosquito abatement strategies. We concluded that enhancing the mosquito death rate results in lower values of ℜ0, and if ℜ0<1, then an epidemic will not occur. Our modeling results provide insights about control strategies of the vector populations and, consequently, a potential decrease in the risk of a WNV outbreak.

  9. How many steps/day are enough? For older adults and special populations

    PubMed Central

    2011-01-01

    Older adults and special populations (living with disability and/or chronic illness that may limit mobility and/or physical endurance) can benefit from practicing a more physically active lifestyle, typically by increasing ambulatory activity. Step counting devices (accelerometers and pedometers) offer an opportunity to monitor daily ambulatory activity; however, an appropriate translation of public health guidelines in terms of steps/day is unknown. Therefore this review was conducted to translate public health recommendations in terms of steps/day. Normative data indicates that 1) healthy older adults average 2,000-9,000 steps/day, and 2) special populations average 1,200-8,800 steps/day. Pedometer-based interventions in older adults and special populations elicit a weighted increase of approximately 775 steps/day (or an effect size of 0.26) and 2,215 steps/day (or an effect size of 0.67), respectively. There is no evidence to inform a moderate intensity cadence (i.e., steps/minute) in older adults at this time. However, using the adult cadence of 100 steps/minute to demark the lower end of an absolutely-defined moderate intensity (i.e., 3 METs), and multiplying this by 30 minutes produces a reasonable heuristic (i.e., guiding) value of 3,000 steps. However, this cadence may be unattainable in some frail/diseased populations. Regardless, to truly translate public health guidelines, these steps should be taken over and above activities performed in the course of daily living, be of at least moderate intensity accumulated in minimally 10 minute bouts, and add up to at least 150 minutes over the week. Considering a daily background of 5,000 steps/day (which may actually be too high for some older adults and/or special populations), a computed translation approximates 8,000 steps on days that include a target of achieving 30 minutes of moderate-to-vigorous physical activity (MVPA), and approximately 7,100 steps/day if averaged over a week. Measured directly and

  10. Health and wellbeing of Victorian adults with intellectual disability compared to the general Victorian population.

    PubMed

    Haider, Syed Imran; Ansari, Zahid; Vaughan, Loretta; Matters, Helen; Emerson, Eric

    2013-11-01

    Multiple measures of health and wellbeing of people with intellectual disability (ID) and the general Victorian population were compared using representative population level data. The sample consisted of adults with ID (N=897) and the general Victorian population (N=34,168) living in the state of Victoria in Australia. Proxy respondents were interviewed on behalf of people with ID, while respondents from the general Victorian population were interviewed directly. The data were weighted to reflect the age/sex/geographic distribution of the population. Results revealed that adults with ID reported higher prevalence of poor social determinants of health, behavioural risk factors, depression, diabetes, poor or fair health. A higher proportion of people with ID reported blood pressure and blood glucose checks, while a lower proportion reported cervical and breast cancer screening, compared with the general Victorian population. The survey identified areas where targeted approaches may be undertaken to improve the health outcomes of people with ID and provide an important understanding of the health and wellbeing of these Victorians.

  11. [Obesity in adults: a population based study in a small town in South of Brazil, 2005].

    PubMed

    Sarturi, Juliana Barbosa; das Neves, Janaina; Peres, Karen Glazer

    2010-01-01

    Changes in nutritional pattern in Brazilian population have been observed mainly in relation to obesity increase. This study aims to estimate the prevalence of obesity and associated factors in adult population in Santo Angelo, Rio Grande do Sul State, 2005. A cross sectional study was carried out involving adult subjects from 20 to 59 years old (n=434), of both sexes. People with Body Mass Index equal to or higher than 30 kg/m(2) were considered obese. A questionnaire was applied to collect data related to socioeconomic, demographic, and behavioral conditions. The multiple logistic regression analysis was performed to identify the associated factors. The response rate was 95.0% and the prevalence of obesity was equal to 16.6% (CI 95% 13.120.1). Presence of obesity was positively associated with lack of physical activity, none feeding habits care, and some individuals that mentioned current health problems regardless of sex. The prevalence of obesity found was similar to other Brazilian population based studies. The results may support planning and implementing prevention actions as well as obesity control in adult population taking into account the relevant details of a small size town.

  12. Acculturation stress, anxiety disorders, and alcohol dependence in a select population of young adult Mexican Americans

    PubMed Central

    Ehlers, Cindy L.; Gilder, David A.; Criado, Jose R.; Caetano, Raul

    2009-01-01

    Objectives Mexican Americans comprise one of the most rapidly growing populations in the U.S. and within this population the process of acculturation has been suggested to be associated with some mental health problems. This study sought to ascertain quantitative information indexing acculturation stress and its association with mental health disorders in a select community sample of Mexican Americans. Methods Demographic information, DSM-III-R diagnoses, and information on cultural identity and acculturation stress were obtained from 240 Mexican American young adults that were recruited by fliers and were residing in selected areas of San Diego. Results No associations were found between measures of cultural identification and lifetime diagnoses of drug or alcohol dependence, major depressive disorder, anxiety disorders or antisocial personality disorder/conduct disorder in this sample of Mexican American young adults. However, lifetime diagnoses of alcohol dependence, substance dependence, and anxiety disorders were associated with elevations in acculturation stress. Conclusion Quantitative measures of acculturation stress, but not cultural identity per se, were found to be significantly associated with substance dependence and anxiety disorders in this select population of Mexican American young adults. These data may be helpful in designing prevention and intervention programs for this high risk population. PMID:20161543

  13. Transmission of tularemia from a water source by transstadial maintenance in a mosquito vector

    NASA Astrophysics Data System (ADS)

    Bäckman, Stina; Näslund, Jonas; Forsman, Mats; Thelaus, Johanna

    2015-01-01

    Mosquitoes are thought to function as mechanical vectors of Francisella tularensis subspecies holarctica (F. t. holarctica) causing tularemia in humans. We investigated the clinical relevance of transstadially maintained F. t. holarctica in mosquitoes. Aedes egypti larvae exposed to a fully virulent F. t. holarctica strain for 24 hours, were allowed to develop into adults when they were individually homogenized. Approximately 24% of the homogenates tested positive for F. t. DNA in PCR. Mice injected with the mosquito homogenates acquired tularemia within 5 days. This novel finding demonstrates the possibility of transmission of bacteria by adult mosquitoes having acquired the pathogen from their aquatic larval habitats.

  14. The Insect Growth Regulator Pyriproxyfen Terminates Egg Diapause in the Asian Tiger Mosquito, Aedes albopictus.

    PubMed

    Suman, Devi S; Wang, Yi; Gaugler, Randy

    2015-01-01

    The Asian tiger mosquito, Aedes albopictus, is a highly invasive mosquito species that transmits chikungunya and dengue. This species overwinters as diapausing eggs in temperate climates. Early diapause termination may be a beneficial strategy for winter mosquito control; however, a mechanism to terminate the diapause process using chemicals is not known. We tested the hypothesis that a hormonal imbalance caused by the administration of juvenile hormone analog would terminate egg diapause in A. albopictus. We tested the insect growth regulator pyriproxyfen on all developmental stages to identify a susceptible stage for diapause termination. We found that pyriproxyfen treatment of mosquito eggs terminated embryonic diapause. The highest rates of diapause termination were recorded in newly deposited (78.9%) and fully embryonated (74.7%) eggs at 0.1 and 1 ppm, respectively. Hatching was completed earlier in newly deposited eggs (25-30 days) compared to fully embryonated eggs (71-80 days). The combined mortality from premature diapause termination and ovicidal activity was 98.2% in newly deposited and >98.9% in fully embryonated eggs at 1 ppm. The control diapause eggs did not hatch under diapausing conditions. Pyriproxyfen exposure to larvae, pupae and adults did not prevent the females from ovipositing diapausing eggs. There was no effect of pyriproxyfen on diapausing egg embryonic developmental time. We also observed mortality in diapausing eggs laid by females exposed to pyriproxyfen immediately after blood feeding. There was no mortality in eggs laid by females that survived larval and pupal exposures. In conclusion, diapausing eggs were the more susceptible to pyriproxyfen diapause termination compared to other life stages. This is the first report of diapause termination in A. albopictus with a juvenile hormone analog. We believe our findings will be useful in developing a new control strategy against overwintering mosquito populations.

  15. Comparison of three residential mosquito traps against riceland mosquitoes in southeast Arkansas.

    PubMed

    Allen, R A; Lewis, C N; Meisch, M V; Dame, D A

    2009-03-01

    Field trials were conducted at 3 locations in Arkansas County, AR, to compare the effectiveness of 3 residential mosquito traps, the Stinger Mosquito Vacuum, the Mosquito Magnet Defender, and the Mosquito Deleto 2500 Active System, against riceland mosquitoes, specifically Anopheles quadrimaculatus and Psorophora columbiae. Both the Stinger Mosquito Vacuum and the Mosquito Deleto captured significantly more An. quadrimaculatus and total mosquitoes than did the Mosquito Magnet Defender. The Mosquito Deleto captured significantly more Ps. columbiae than did either of the other 2 traps.

  16. Carbamate-resistance in mosquitos

    PubMed Central

    Georghiou, G. P.; Metcalf, R. L.; Gidden, Frances E.

    1966-01-01

    The authors investigated the rate of development and other characteristics of Baygon-resistance in Culex pipiens fatigans (=C. quinquefasciatus) recently colonized from Southern California. Selective pressure against the larvae (strain L) for 35 generations resulted in 25.4-fold resistance in larvae, but only 3-fold and 4.8-fold resistance in adults, as determined by contact and topical application, respectively. Conversely, selective pressure on adults (strain A) for 24 generations resulted in 8.4-fold (contact) and 5.3-fold (topical) resistance in adults, but only 2.7-fold resistance in larvae. About 10% of strain A adults survived 1-hour contact exposure even when the concentration of Baygon was increased 100-fold. This was not due to enhanced phototropism in this stage. Larvae of strain L metabolized 14C-labelled Baygon at a rate 2.5-fold greater than the non-selected strain. Cross-resistance in strain L to carbamates closely related to Baygon was high, but was extremely low to remotely related carbamates. The authors consider the relatively slow rate of development of resistance to Baygon, the reduced expressivity of the resistance character in adults, and its specificity for the selective agent and for closely related carbamates to be encouraging indications as to the usefulness of this class of compounds for mosquito control. PMID:5297803

  17. Spatial-temporal analysis of Cache Valley virus (Bunyaviridae: Orthobunyavirus) infection in anopheline and culicine mosquitoes (Diptera: Culicidae) in the northeastern United States, 1997-2012.

    PubMed

    Andreadis, Theodore G; Armstrong, Philip M; Anderson, John F; Main, Andrew J

    2014-10-01

    mosquito abundance. Virus infection in mosquitoes occurred late in the season that mostly extended from mid-August through September, when adult mosquito populations were visibly declining and were comparatively low. Findings argue for a limited role for vertical transmission for the perpetuation of CVV as occurs with other related bunyaviruses.

  18. Spatial-Temporal Analysis of Cache Valley Virus (Bunyaviridae: Orthobunyavirus) Infection in Anopheline and Culicine Mosquitoes (Diptera: Culicidae) in the Northeastern United States, 1997–2012

    PubMed Central

    Armstrong, Philip M.; Anderson, John F.; Main, Andrew J.

    2014-01-01

    overall mosquito abundance. Virus infection in mosquitoes occurred late in the season that mostly extended from mid-August through September, when adult mosquito populations were visibly declining and were comparatively low. Findings argue for a limited role for vertical transmission for the perpetuation of CVV as occurs with other related bunyaviruses. PMID:25325321

  19. Intentional genetic introgression influences survival of adults and subadults in a small, inbred felid population.

    PubMed

    Benson, John F; Hostetler, Jeffrey A; Onorato, David P; Johnson, Warren E; Roelke, Melody E; O'Brien, Stephen J; Jansen, Deborah; Oli, Madan K

    2011-09-01

    1. Inbreeding and low genetic diversity can cause reductions in individual fitness and increase extinction risk in animal populations. Intentional introgression, achieved by releasing genetically diverse individuals into inbred populations, has been used as a conservation tool to improve demographic performance in endangered populations. 2. By the 1980s, Florida panthers (Puma concolor coryi) had been reduced to a small, inbred population that appeared to be on the brink of extinction. In 1995, female pumas from Texas (P. c. stanleyana) were released in occupied panther range as part of an intentional introgression programme to restore genetic variability and improve demographic performance of panthers. 3. We used 25 years (1981-2006) of continuous radiotelemetry and genetic data to estimate and model subadult and adult panther survival and cause-specific mortality to provide rigorous sex and age class-specific survival estimates and evaluate the effect of the introgression programme on these parameters. 4. Genetic ancestry influenced annual survival of subadults and adults after introgression, as F(1) generation admixed panthers ( = 0·98) survived better than pre-introgression type panthers ( = 0·77) and other admixed individuals ( = 0·82). Furthermore, heterozygosity was higher for admixed panthers relative to pre-introgression type panthers and positively influenced survival. 5. Our results are consistent with hybrid vigour; however, extrinsic factors such as low density of males in some areas of panther range may also have contributed to higher survival of F(1) panthers. Regardless, improved survival of F(1) subadults and adults likely contributed to the numerical increase in panthers following introgression, and our results indicate that intentional admixture, achieved here by releasing individuals from another population, appears to have been successful in improving demographic performance in this highly endangered population.

  20. Differences in absorption, distribution, metabolism and excretion of xenobiotics between the paediatric and adult populations.

    PubMed

    Strolin Benedetti, M; Whomsley, R; Baltes, E L

    2005-10-01

    In children, the therapeutic benefits and potential risks associated with drug treatment may be different from those in adults and will depend on the exposure, receptor sensitivity and relationship between effect and exposure. In this paper, key factors undergoing maturational changes accounting for differences in drug metabolism and disposition in the paediatric population compared with adults are reviewed. Gastric and duodenal pH, gastric emptying time, intestinal transit time, secretion and activity of bile and pancreatic fluid, bacterial colonisation and transporters, such as P-glycoprotein (P-gp), are important factors for drug absorption, whereas key factors explaining differences in drug distribution between the paediatric population and adults are organ size, membrane permeability, plasma protein concentration and characteristics, endogenous substances in plasma, total body and extracellular water, fat content, regional blood flow and transporters such as P-gp, which is present not only in the gut, but also in liver, kidney, brain and other tissues. As far as drug metabolism is concerned, important differences have been found in the paediatric population compared with adults both for phase I enzymes (oxidative [e.g., cytochrome P450 (CYP)1A2, and CYP3A7 versus -3A4], reductive and hydrolytic enzymes) and phase II enzymes (e.g., N-methyltransferases and glucuronosyltransferases). Generally, the major enzyme differences observed in comparison with the adult age are in newborn infants, although for some enzymes (e.g., glucuronosyltransferases and other phase II enzymes) important differences still exist between infants and toddlers and adults. Finally, key factors undergoing maturational changes accounting for differences in renal excretion in the paediatric population compared with adults are glomerular filtration and tubular secretion. The ranking of the key factors varies according to the chemical structure and physicochemical properties of the drug

  1. A juvenile-adult population model: climate change, cannibalism, reproductive synchrony, and strong Allee effects.

    PubMed

    Veprauskas, Amy; Cushing, J M

    2017-03-01

    We study a discrete time, structured population dynamic model that is motivated by recent field observations concerning certain life history strategies of colonial-nesting gulls, specifically the glaucous-winged gull (Larus glaucescens). The model focuses on mechanisms hypothesized to play key roles in a population's response to degraded environment resources, namely, increased cannibalism and adjustments in reproductive timing. We explore the dynamic consequences of these mechanics using a juvenile-adult structure model. Mathematically, the model is unusual in that it involves a high co-dimension bifurcation at [Formula: see text] which, in turn, leads to a dynamic dichotomy between equilibrium states and synchronized oscillatory states. We give diagnostic criteria that determine which dynamic is stable. We also explore strong Allee effects caused by positive feedback mechanisms in the model and the possible consequence that a cannibalistic population can survive when a non-cannibalistic population cannot.

  2. Field performance of engineered male mosquitoes.

    PubMed

    Harris, Angela F; Nimmo, Derric; McKemey, Andrew R; Kelly, Nick; Scaife, Sarah; Donnelly, Christl A; Beech, Camilla; Petrie, William D; Alphey, Luke

    2011-10-30

    Dengue is the most medically important arthropod-borne viral disease, with 50-100 million cases reported annually worldwide. As no licensed vaccine or dedicated therapy exists for dengue, the most promising strategies to control the disease involve targeting the predominant mosquito vector, Aedes aegypti. However, the current methods to do this are inadequate. Various approaches involving genetically engineered mosquitoes have been proposed, including the release of transgenic sterile males. However, the ability of laboratory-reared, engineered male mosquitoes to effectively compete with wild males in terms of finding and mating with wild females, which is critical to the success of these strategies, has remained untested. We report data from the first open-field trial involving a strain of engineered mosquito. We demonstrated that genetically modified male mosquitoes, released across 10 hectares for a 4-week period, mated successfully with wild females and fertilized their eggs. These findings suggest the feasibility of this technology to control dengue by suppressing field populations of A. aegypti.

  3. Links between Childhood and Adult Social Circumstances and Obesity and Hypertension in the Mexican Population

    PubMed Central

    Beltrán-Sánchez, Hiram; Crimmins, Eileen M.; Teruel, Graciela M.; Thomas, Duncan

    2011-01-01

    Objectives This study examines links between early life circumstances and adult socioeconomic status and obesity and hypertension in the adult Mexican population. Methods We use data from the Mexican Family Life Survey (MxFLS) collected in 2002 for people aged 20 or older (N=14, 280). Results We found that men with low education and women with more education have significantly lower obesity. Women with higher education also have significantly less hypertension. Obesity triples the likelihood of hypertension among both men and women. Better childhood experiences are associated with less hypertension among women, but more hypertension among men in rural areas. Discussion Recent changes in income, nutrition, and infection in Mexico may be responsible for the observed high prevalence of overweight and obesity and the extremely high odds of hypertension among obese young adults. PMID:21948773

  4. Culex (Culex) declarator, a mosquito species new to Florida.

    PubMed

    Darsie, Richard F; Shroyer, Donald A

    2004-09-01

    One specimen of a mosquito new to Florida, Culex declarator, was first found in 1998 in Indian River County. A 2nd specimen was collected in 2002. Beginning in September 2003, Cx. declarator adults were regularly encountered in routine mosquito surveillance sampling, with more than 300 specimens appearing in 45 collections. Prior to our find, the U.S. distrubution was thought to be restricted to south Texas. The full extent of this species' distribution in Florida has yet to be determined.

  5. The isolation of spiroplasmas from mosquitoes in Macon County, Alabama.

    PubMed

    Shaikh, A A; Johnson, W E; Stevens, C; Tang, A Y

    1987-06-01

    During the summer months of 1985, 1,298 adult mosquitoes comprising 21 species and 7 genera were collected in Macon County, Alabama. Mosquitoes were collected from four sections of the county with CO2-baited light traps. Spiroplasma cultures were isolated from two pools of 24 and 25 Aedes fulvus pallens, one pool of 22 Anopheles punctipennis and one pool of 7 Culex nigripalpus. Electron microscopic studies of the isolates revealed helical, wall-less cells.

  6. Spinosad: a biorational mosquito larvicide for use in car tires in southern Mexico

    PubMed Central

    2012-01-01

    Background Car tires are important habitats for mosquito development because of the high density populations they can harbor and their presence in urban settings. Water in experimental tires was treated with one of three insecticides or an untreated control. Aquatic invertebrates were sampled at weekly intervals. Eggs, larval and pupal samples were laboratory-reared to estimate seasonal fluctuations in Aedes aegypti and Ae. albopictus abundance. Results Spinosad treatments at 1 or 5 ppm (mg a.i./liter) provided 6–8 weeks of effective control of Ae. aegypti, Ae. albopictus, Culex quinquefasiatus and Cx. coronator larvae, both in the dry season and the rainy season when mosquito populations increased markedly in southern Mexico. Spinosad continued to provide partial control of larvae for several weeks after initial recolonization of treated tires. The larvicidal performance of VectoBac 12AS (Bacillus thuringiensis var. israelensis) was relatively poor with one week of complete control of Aedes spp. larvae and no discernible control of Culex spp., whereas the duration of larvicidal activity of 1% temephos mineral-based granules was intermediate between those of VectoBac and spinosad treatments. Populations of chironomids, ostracods and Toxorhynchites theobaldi were generally reduced in spinosad and temephos treatments, but were similar in control and VectoBac treatments. Conclusion The present study is the first to report spinosad as an effective larvicide against Cx. coronator, which is currently invading the southern United States. These results substantiate the use of spinosad as a highly effective mosquito larvicide, even in habitats such as unused car tires that can represent prolific sources of adult mosquitoes. PMID:22608138

  7. Variation in Aedes aegypti Mosquito Competence for Zika Virus Transmission.

    PubMed

    Roundy, Christopher M; Azar, Sasha R; Rossi, Shannan L; Huang, Jing H; Leal, Grace; Yun, Ruimei; Fernandez-Salas, Ildefonso; Vitek, Christopher J; Paploski, Igor A D; Kitron, Uriel; Ribeiro, Guilherme S; Hanley, Kathryn A; Weaver, Scott C; Vasilakis, Nikos

    2017-04-01

    To test whether Zika virus has adapted for more efficient transmission by Aedes aegypti mosquitoes, leading to recent urban outbreaks, we fed mosquitoes from Brazil, the Dominican Republic, and the United States artificial blood meals containing 1 of 3 Zika virus strains (Senegal, Cambodia, Mexico) and monitored infection, dissemination, and virus in saliva. Contrary to our hypothesis, Cambodia and Mexica strains were less infectious than the Senegal strain. Only mosquitoes from the Dominican Republic transmitted the Cambodia and Mexica strains. However, blood meals from viremic mice were more infectious than artificial blood meals of comparable doses; the Cambodia strain was not transmitted by mosquitoes from Brazil after artificial blood meals, whereas 61% transmission occurred after a murine blood meal (saliva titers up to 4 log 10 infectious units/collection). Although regional origins of vector populations and virus strain influence transmission efficiency, Ae. aegypti mosquitoes appear to be competent vectors of Zika virus in several regions of the Americas.

  8. Variation in Aedes aegypti Mosquito Competence for Zika Virus Transmission

    PubMed Central

    Roundy, Christopher M.; Azar, Sasha R.; Rossi, Shannan L.; Huang, Jing H.; Leal, Grace; Yun, Ruimei; Fernandez-Salas, Ildefonso; Vitek, Christopher J.; Paploski, Igor A.D.; Kitron, Uriel; Ribeiro, Guilherme S.; Hanley, Kathryn A.

    2017-01-01

    To test whether Zika virus has adapted for more efficient transmission by Aedes aegypti mosquitoes, leading to recent urban outbreaks, we fed mosquitoes from Brazil, the Dominican Republic, and the United States artificial blood meals containing 1 of 3 Zika virus strains (Senegal, Cambodia, Mexico) and monitored infection, dissemination, and virus in saliva. Contrary to our hypothesis, Cambodia and Mexica strains were less infectious than the Senegal strain. Only mosquitoes from the Dominican Republic transmitted the Cambodia and Mexica strains. However, blood meals from viremic mice were more infectious than artificial blood meals of comparable doses; the Cambodia strain was not transmitted by mosquitoes from Brazil after artificial blood meals, whereas 61% transmission occurred after a murine blood meal (saliva titers up to 4 log10 infectious units/collection). Although regional origins of vector populations and virus strain influence transmission efficiency, Ae. aegypti mosquitoes appear to be competent vectors of Zika virus in several regions of the Americas. PMID:28287375

  9. Mosquito Vectors and the Globalization of Plasmodium falciparum Malaria.

    PubMed

    Molina-Cruz, Alvaro; Zilversmit, Martine M; Neafsey, Daniel E; Hartl, Daniel L; Barillas-Mury, Carolina

    2016-11-23

    Plasmodium falciparum malaria remains a devastating public health problem. Recent discoveries have shed light on the origin and evolution of Plasmodium parasites and their interactions with their vertebrate and mosquito hosts. P. falciparum malaria originated in Africa from a single horizontal transfer between an infected gorilla and a human, and became global as the result of human migration. Today, P. falciparum malaria is transmitted worldwide by more than 70 different anopheline mosquito species. Recent studies indicate that the mosquito immune system can be a barrier to malaria transmission and that the P. falciparum Pfs47 gene allows the parasite to evade mosquito immune detection. Here, we review the origin and globalization of P. falciparum and integrate this history with analysis of the biology, evolution, and dispersal of the main mosquito vectors. This new perspective broadens our understanding of P. falciparum population structure and the dispersal of important parasite genetic traits.

  10. Dissecting vectorial capacity for mosquito-borne viruses

    PubMed Central

    Kramer, Laura D.; Ciota, Alexander T.

    2015-01-01

    The inter-relationship between mosquitoes and the viruses they transmit is complex. While previously understood barriers to infection and transmission remain valid, additional factors have been uncovered that suggest an “arms race” between mosquito and virus. These include the mosquito microbiota and interplay between mosquito and viral genetics. Following an infectious blood meal, the mosquito mounts an immune and transcriptional response, leading to altered expression of multiple genes. These complex interactions, specific to vector and virus genotypes, combine with external influences, particularly temperature, to determine vector competence. The mosquito’s response to the infecting agent may have consequences in terms of longevity, feeding behavior and/or fecundity. These factors, together with population density and the frequency of host contact determine vectorial capacity. PMID:26569343

  11. Seroepidemiology of dengue virus infection in the adult population in tropical Singapore.

    PubMed

    Ang, L W; Cutter, J; James, L; Goh, K T

    2015-06-01

    To assess the impact of past dengue epidemics in Singapore, we undertook a national seroepidemiological study to determine the prevalence of past dengue virus (DENV) infection in the adult population in 2010 and make comparisons with the seroprevalence in 2004. The study involved residual sera from 3293 adults aged 18-79 years who participated in a national health survey in 2010. The overall prevalence of anti-DENV IgG antibodies was 56·8% (95% confidence interval 55·1-58·5) in 2010. The seroprevalence increased significantly with age. Males had significantly higher seroprevalence than females (61·5% vs. 53·2%). Among the three major ethnic groups, Malays had the lowest seroprevalence (50·2%) compared to Chinese (57·0%) and Indians (62·0%). The age-standardized seroprevalence in adults was significantly lower in 2010 (54·4%) compared to 2004 (63·1%). Older age, male gender, Indian ethnicity, permanent residency and being home-bound were independent risk factors significantly associated with seropositivity. About 43% of the Singapore adult resident population remain susceptible to DENV infection as a result of the successful implementation of a comprehensive nationwide Aedes surveillance and control programme since the 1970s. Vector suppression and concerted efforts of all stakeholders in the community remain the key strategy in the prevention and control of dengue.

  12. Amplifying diffusion of health information in low-literate populations through adult education health literacy classes.

    PubMed

    Freedman, Ariela M; Miner, Kathleen R; Echt, Katharina V; Parker, Ruth; Cooper, Hannah L F

    2011-01-01

    Over the next decade, as literacy rates are predicted to decline, the health care sector faces increasing challenges to effective communication with low-literate groups. Considering the rising costs of health care and the forthcoming changes in the American health care system, it is imperative to find nontraditional avenues through which to impart health knowledge and functional skills. This article draws on classroom observations and qualitative interviews with 21 students and 3 teachers in an adult education health literacy class to explore the efficacy of using adult education courses to teach functional health literacy skills to low-literate populations. Data were analyzed using a combination of thematic and content analyses. Results describe the motivation of students to share information within the classroom and with friends and family outside the classroom. This article also provides several recommendations to help ensure accuracy of diffused information both within and outside of the classroom. Ultimately, this study suggests that the adult education system is in a prime position to impart functional health literacy skills to low-literate populations in the classroom. Significantly, this study demonstrates that adult education students themselves may be a powerful vehicle for health communication beyond the walls of the classroom.

  13. Increased reports of measles in a low endemic region during a rubella outbreak in adult populations.

    PubMed

    Kurata, Takako; Kanbayashi, Daiki; Nishimura, Hiroshi; Komano, Jun; Kase, Tetsuo; Takahashi, Kazuo

    2015-06-01

    In 2013, a rubella outbreak was observed in Japan, Romania, and Poland. The outbreak in Japan was accompanied by an increase of measles reports, especially from a region where measles is highly controlled. This was attributed to the adult populations affected by this rubella outbreak, similarity of clinical signs between rubella and measles, sufficiently small impact of measles outbreaks from neighboring nations, and elimination levels of measles endemicity. Current and future concerns for measles control are discussed.

  14. Human growth hormone (GH1) gene polymorphism map in a normal-statured adult population

    PubMed Central

    Esteban, Cristina; Audí, Laura; Carrascosa, Antonio; Fernández-Cancio, Mónica; Pérez-Arroyo, Annalisa; Ulied, Angels; Andaluz, Pilar; Arjona, Rosa; Albisu, Marian; Clemente, María; Gussinyé, Miquel; Yeste, Diego

    2007-01-01

    Objective GH1 gene presents a complex map of single nucleotide polymorphisms (SNPs) in the entire promoter, coding and noncoding regions. The aim of the study was to establish the complete map of GH1 gene SNPs in our control normal population and to analyse its association with adult height. Design, subjects and measurements A systematic GH1 gene analysis was designed in a control population of 307 adults of both sexes with height normally distributed within normal range for the same population: −2 standard deviation scores (SDS) to +2 SDS. An analysis was performed on individual and combined genotype associations with adult height. Results Twenty-five SNPs presented a frequency over 1%: 11 in the promoter (P1 to P11), three in the 5′UTR region (P12 to P14), one in exon 1 (P15), three in intron 1 (P16 to P18), two in intron 2 (P19 and P20), two in exon 4 (P21 and P22) and three in intron 4 (P23 to P25). Twenty-nine additional changes with frequencies under 1% were found in 29 subjects. P8, P19, P20 and P25 had not been previously described. P6, P12, P17 and P25 accounted for 6·2% of the variation in adult height (P = 0·0007) in this population with genotypes A/G at P6, G/G at P6 and A/G at P12 decreasing height SDS (−0·063 ± 0·031, −0·693 ± 0·350 and −0·489 ± 0·265, Mean ± SE) and genotypes A/T at P17 and T/G at P25 increasing height SDS (+1·094 ± 0·456 and +1·184 ± 0·432). Conclusions This study established the GH1 gene sequence variation map in a normal adult height control population confirming the high density of SNPs in a relatively small gene. Our study shows that the more frequent SNPs did not significantly contribute to height determination, while only one promoter and two intronic SNPs contributed significantly to it. Studies in larger populations will have to confirm the associations and in vitro functional studies will elucidate the mechanisms involved. Systematic GH1 gene analysis in patients with growth delay and suspected

  15. The Effect of HIFA Waiver Expansions on Uninsurance Rates in Adult Populations

    PubMed Central

    Atherly, Adam; Dowd, Bryan E; Coulam, Robert F; Guy, Gery

    2012-01-01

    Research Objective To evaluate the effect of the Health Insurance Flexibility and Accountability (HIFA) demonstrations on the rate of uninsured. The policy purpose of the HIFA demonstrations is to encourage “new comprehensive state approaches” that will increase the number of insured. HIFA interventions include changes in benefit packages, eligibility rules for public programs, and state subsidization of private health insurance premiums. Some states emphasized private insurance (premium assistance), whereas others placed greater emphasis on expanded eligibility for public insurance. Data Sources/Study Setting Data were drawn from the Current Population Survey from 2000 to 2007. The target populations for the HIFA waiver demonstrations consisted of individuals who were eligible for the HIFA waiver demonstrations in demonstration states. Study Design The estimation approach was a probit model using a difference-in-differences approach. Principal Findings In states that fully implemented their HIFA waiver, HIFA increased the rate of insurance coverage by 6.4 percentage points on average in the targeted adult population, suggesting that approximately 118,848 adults gained health insurance due to HIFA. Total HIFA adult enrollment in the six states studied was 280,739. The effect size varied by state, with Maine having the largest effect and Illinois the smallest. The results were robust to different specifications of the control group. Conclusions Our findings suggest that public insurance initiatives that provide states with flexibility regarding eligibility and plan design are a viable policy approach to reducing uninsurance rates. PMID:22299673

  16. Mosquitoes rely on their gut microbiota for development

    PubMed Central

    Coon, Kerri L.; Vogel, Kevin J.; Brown, Mark R.; Strand, Michael R.

    2014-01-01

    Field studies indicate adult mosquitoes (Culicidae) host low diversity communities of bacteria that vary greatly among individuals and species. In contrast, it remains unclear how adult mosquitoes acquire their microbiome, what influences community structure, and whether the microbiome is important for survival. Here we used pyrosequencing of 16S rRNA to characterize the bacterial communities of three mosquito species reared under identical conditions. Two of these species, Aedes aegypti and Anopheles gambiae, are anautogenous and must blood feed to produce eggs, while one, Georgecraigius atropalpus, is autogenous and produces eggs without blood feeding. Each mosquito species contained a low diversity community comprised primarily of aerobic bacteria acquired primarily from the aquatic habitat in which larvae developed. Our results suggested the communities in Ae. aegypti and An. gambiae larvae share more similarities with one another than with Ge. atropalpus. Studies with Ae. aegypti also strongly suggested that adults transstadially acquired several members of the larval bacterial community, but only four genera of bacteria present in blood fed females were detected on eggs. Functional assays showed that axenic larvae of each species failed to develop beyond the first instar. Experiments with Ae. aegypti indicated several members of the microbial community and Escherichia coli successfully colonized axenic larvae and rescued development. Overall, our results provide new insights about the acquisition and structure of bacterial communities in mosquitoes. They also indicate three mosquito species spanning the breadth of the Culicidae depend on their gut microbiome for development. PMID:24766707

  17. Using remote sensing to map larval and adult populations of Anopheles hyrcanus (Diptera: Culicidae) a potential malaria vector in Southern France

    PubMed Central

    Tran, Annelise; Ponçon, Nicolas; Toty, Céline; Linard, Catherine; Guis, Hélène; Ferré, Jean-Baptiste; Lo Seen, Danny; Roger, François; de la Rocque, Stéphane; Fontenille, Didier; Baldet, Thierry

    2008-01-01

    Background Although malaria disappeared from southern France more than 60 years ago, suspicions of recent autochthonous transmission in the French Mediterranean coast support the idea that the area could still be subject to malaria transmission. The main potential vector of malaria in the Camargue area, the largest river delta in southern France, is the mosquito Anopheles hyrcanus (Diptera: Culicidae). In the context of recent climatic and landscape changes, the evaluation of the risk of emergence or re-emergence of such a major disease is of great importance in Europe. When assessing the risk of emergence of vector-borne diseases, it is crucial to be able to characterize the arthropod vector's spatial distribution. Given that remote sensing techniques can describe some of the environmental parameters which drive this distribution, satellite imagery or aerial photographs could be used for vector mapping. Results In this study, we propose a method to map larval and adult populations of An. hyrcanus based on environmental indices derived from high spatial resolution imagery. The analysis of the link between entomological field data on An. hyrcanus larvae and environmental indices (biotopes, distance to the nearest main productive breeding sites of this species i.e., rice fields) led to the definition of a larval index, defined as the probability of observing An. hyrcanus larvae in a given site at least once over a year. Independent accuracy assessments showed a good agreement between observed and predicted values (sensitivity and specificity of the logistic regression model being 0.76 and 0.78, respectively). An adult index was derived from the larval index by averaging the larval index within a buffer around the trap location. This index was highly correlated with observed adult abundance values (Pearson r = 0.97, p < 0.05). This allowed us to generate predictive maps of An. hyrcanus larval and adult populations from the landscape indices. Conclusion This work shows

  18. Diffusely adherent Escherichia coli strains isolated from children and adults constitute two different populations

    PubMed Central

    2013-01-01

    Background Diffusely adherent Escherichia coli (DAEC) have been considered a diarrheagenic category of E. coli for which several potential virulence factors have been described in the last few years. Despite this, epidemiological studies involving DAEC have shown inconsistent results. In this work, two different collections of DAEC possessing Afa/Dr genes, from children and adults, were studied regarding characteristics potentially associated to virulence. Results DAEC strains were recovered in similar frequencies from diarrheic and asymptomatic children, and more frequently from adults with diarrhea (P < 0.01) than from asymptomatic adults. Association with diarrhea (P < 0.05) was found for SAT-positive strains recovered from children and for curli-positive strains recovered from adults. Mixed biofilms involving DAEC and a Citrobacter freundii strain have shown an improved ability to form biofilms in relation to the monocultures. Control strains have shown a greater diversity of Afa/Dr adhesins and higher frequencies of cellulose, TTSS, biofilm formation and induction of IL-8 secretion than strains from cases of diarrhea in children. Conclusions DAEC strains possessing Afa/Dr genes isolated from children and adults represent two different bacterial populations. DAEC strains carrying genes associated to virulence can be found as part of the normal microbiota present in asymptomatic children. PMID:23374248

  19. Adult mortality in a low-density tree population using high-resolution remote sensing.

    PubMed

    Kellner, James R; Hubbell, Stephen P

    2017-04-04

    We developed a statistical framework to quantify mortality rates in canopy trees observed using time series from high-resolution remote sensing. By timing the acquisition of remote sensing data with synchronous annual flowering in the canopy tree species Handroanthus guayacan, we made 2,596 unique detections of 1,006 individual adult trees within 18,883 observation attempts on Barro Colorado Island, Panama (BCI) during an 11-year period. There were 1,057 observation attempts that resulted in missing data due to cloud cover or incomplete spatial coverage. Using the fraction of 123 individuals from an independent field sample that were detected by satellite data (109 individuals, 88.6%), we estimate that the adult population for this species on BCI was 1,135 individuals. We used a Bayesian state-space model that explicitly accounted for the probability of tree detection and missing observations to compute an annual adult mortality rate of 0.2% · yr(-1) (SE = 0.1, 95% CI = 0.06 - 0.45). An independent estimate of the adult mortality rate from 260 field-checked trees closely matched the landscape-scale estimate (0.33% · yr(-1) , SE = 0.16, 95% CI = 0.12 - 0.74). Our proof-of-concept study shows that one can remotely estimate adult mortality rates for canopy tree species precisely in the presence of variable detection and missing observations. This article is protected by copyright. All rights reserved.

  20. Insecticide resistance status of United States populations of Aedes albopictus and mechanisms involved

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aedes albopictus (Skuse) is an invasive mosquito that has become an important vector of chikungunya and dengue viruses. Immature Ae. albopictus thrive in backyard household containers that require treatment with larvicides and when adult populations reach pest levels or disease transmission is ongoi...

  1. Levels of Health Literacy in a Community-Dwelling Population of Chinese Older Adults

    PubMed Central

    Li, Yu; Dong, XinQi

    2014-01-01

    Background. Lower levels of health literacy have been associated with adverse health outcomes, especially for older adults. However, limited research has been conducted to understand health literacy levels among Chinese American older adults. Methods. The PINE study is an epidemiological cohort of 3,159 community-dwelling Chinese older adults, 95% of whom do not speak or read English. Chinese older adults’ health literacy levels were examined using the Chinese version of the Rapid Estimate of Adult Literacy in Medicine, Revised (REALM-R) test. Kruskal–Wallis test and chi-square statistics were used to identify significant differences by sociodemographic and self-reported health characteristics. Pearson and Spearman correlation coefficients were used to examine correlations between personal characteristics and health literacy level. Results. The mean age among this sample of Chinese older adults was 72.8 years (SD = 8.3, range = 60–105) and the mean REALM-R test score was 6.9 [SD = 2.3, range (0–8)]. Health literacy was positively associated with education, marriage status, and number of people living with. Older age, being female, greater number of children, years in the United States, and preference for speaking Cantonese or Taishanese were negatively associated with health literacy. Health literary was not associated with self-reported health status or quality of life. Conclusions. In this Chicago Chinese population, older adults had reasonable levels of health literacy in Chinese. Future longitudinal research is needed to understand risk/protective factors associated with health literacy level in Chinese older adults. PMID:25378449

  2. Prevalence of self-medication in the adult population of Brazil: a systematic review

    PubMed Central

    Domingues, Paulo Henrique Faria; Galvão, Taís Freire; de Andrade, Keitty Regina Cordeiro; de Sá, Pedro Terra Teles; Silva, Marcus Tolentino; Pereira, Mauricio Gomes

    2015-01-01

    OBJECTIVE To evaluate the prevalence of self-medication in Brazil’s adult population. METHODS Systematic review of cross-sectional population-based studies. The following databases were used: Medline, Embase, Scopus, ISI, CINAHL, Cochrane Library, CRD, Lilacs, SciELO, the Banco de teses brasileiras (Brazilian theses database) (Capes) and files from the Portal Domínio Público (Brazilian Public Domain). In addition, the reference lists from relevant studies were examined to identify potentially eligible articles. There were no applied restrictions in terms of the publication date, language or publication status. Data related to publication, population, methods and prevalence of self-medication were extracted by three independent researchers. Methodological quality was assessed following eight criteria related to sampling, measurement and presentation of results. The prevalences were measured from participants who used at least one medication during the recall period of the studies. RESULTS The literature screening identified 2,778 records, from which 12 were included for analysis. Most studies were conducted in the Southeastern region of Brazil, after 2000 and with a 15-day recall period. Only five studies achieved high methodological quality, of which one study had a 7-day recall period, in which the prevalence of self-medication was 22.9% (95%CI 14.6;33.9). The prevalence of self-medication in three studies of high methodological quality with a 15-day recall period was 35.0% (95%CI 29.0;40.0, I2 = 83.9%) in the adult Brazilian population. CONCLUSIONS Despite differences in the methodologies of the included studies, the results of this systematic review indicate that a significant proportion of the adult Brazilian population self-medicates. It is suggested that future research projects that assess self-medication in Brazil standardize their methods. PMID:26083944

  3. Space-use, movement and dispersal of sub-adult cougars in a geographically isolated population

    PubMed Central

    Boyce, Mark S.; Nielsen, Scott E.

    2015-01-01

    Cougar (Puma concolor) observations have increased in Midwest North America, with breeding populations re-establishing in several regions east of their contemporary range. The Cypress Hills Uplands, located in southwest Saskatchewan and southeast Alberta, was recently re-colonized by cougars and now supports the easternmost confirmed breeding population of cougars in Canada. A number of factors contribute to this cougar range expansion, but it is dispersal that provides the mechanism for re-colonization of historic range. We used GPS-collar data to examine space-use and movement behavior of sub-adult cougars, the age class associated with dispersal, in the Cypress Hills. Conditional logistic regression and a two-stage modeling approach were used to estimate resource selection functions (RSF) of sub-adult cougars during two distinct ranging behaviors: transient movements (i.e., dispersal and exploratory forays) and localizing movements (i.e., temporary home ranges). Linear regression was used to model movement rates, measured as the distance between consecutive 3-h GPS-relocations, of sub-adult cougars relative to different habitats, times of day and between transient and localizing behavior. All individual sub-adult cougars displayed bouts of transient and localizing behavior. All male cougars dispersed from their natal ranges and travelled considerably farther distances than female cougars. One male dispersed over 750 km eastward through the agricultural belt of northern Montana and southern Saskatchewan. Males occupied temporary home ranges in more open habitats on the fringes of the insular Cypress Hills, while females appeared to be recruited into the adult population, occupying treed habitat that provided more suitable cover. During both ranging behaviors, sub-adult cougars selected for rugged terrain and proximity to hydrological features (likely supporting riparian habitats) and avoided open cover types. Differences in habitat selection between ranging

  4. Space-use, movement and dispersal of sub-adult cougars in a geographically isolated population.

    PubMed

    Morrison, Carl D; Boyce, Mark S; Nielsen, Scott E

    2015-01-01

    Cougar (Puma concolor) observations have increased in Midwest North America, with breeding populations re-establishing in several regions east of their contemporary range. The Cypress Hills Uplands, located in southwest Saskatchewan and southeast Alberta, was recently re-colonized by cougars and now supports the easternmost confirmed breeding population of cougars in Canada. A number of factors contribute to this cougar range expansion, but it is dispersal that provides the mechanism for re-colonization of historic range. We used GPS-collar data to examine space-use and movement behavior of sub-adult cougars, the age class associated with dispersal, in the Cypress Hills. Conditional logistic regression and a two-stage modeling approach were used to estimate resource selection functions (RSF) of sub-adult cougars during two distinct ranging behaviors: transient movements (i.e., dispersal and exploratory forays) and localizing movements (i.e., temporary home ranges). Linear regression was used to model movement rates, measured as the distance between consecutive 3-h GPS-relocations, of sub-adult cougars relative to different habitats, times of day and between transient and localizing behavior. All individual sub-adult cougars displayed bouts of transient and localizing behavior. All male cougars dispersed from their natal ranges and travelled considerably farther distances than female cougars. One male dispersed over 750 km eastward through the agricultural belt of northern Montana and southern Saskatchewan. Males occupied temporary home ranges in more open habitats on the fringes of the insular Cypress Hills, while females appeared to be recruited into the adult population, occupying treed habitat that provided more suitable cover. During both ranging behaviors, sub-adult cougars selected for rugged terrain and proximity to hydrological features (likely supporting riparian habitats) and avoided open cover types. Differences in habitat selection between ranging

  5. Transgenic malaria-resistant mosquitoes have a fitness advantage when feeding on Plasmodium-infected blood.

    PubMed

    Marrelli, Mauro T; Li, Chaoyang; Rasgon, Jason L; Jacobs-Lorena, Marcelo

    2007-03-27

    The introduction of genes that impair Plasmodium development into mosquito populations is a strategy being considered for malaria control. The effect of the transgene on mosquito fitness is a crucial parameter influencing the success of this approach. We have previously shown that anopheline mosquitoes expressing the SM1 peptide in the midgut lumen are impaired for transmission of Plasmodium berghei. Moreover, the transgenic mosquitoes had no noticeable fitness load compared with nontransgenic mosquitoes when fed on noninfected mice. Here we show that when fed on mice infected with P. berghei, these transgenic mosquitoes are more fit (higher fecundity and lower mortality) than sibling nontransgenic mosquitoes. In cage experiments, transgenic mosquitoes gradually replaced nontransgenics when mosquitoes were maintained on mice infected with gametocyte-producing parasites (strain ANKA 2.34) but not when maintained on mice infected with gametocyte-deficient parasites (strain ANKA 2.33). These findings suggest that when feeding on Plasmodium-infected blood, transgenic malaria-resistant mosquitoes have a selective advantage over nontransgenic mosquitoes. This fitness advantage has important implications for devising malaria control strategies by means of genetic modification of mosquitoes.

  6. Inhibition of Malaria Infection in Transgenic Anopheline Mosquitoes Lacking Salivary Gland Cells

    PubMed Central

    Kasashima, Katsumi; Sezutsu, Hideki; Matsuoka, Hiroyuki

    2016-01-01

    Malaria is an important global public health challenge, and is transmitted by anopheline mosquitoes during blood feeding. Mosquito vector control is one of the most effective methods to control malaria, and population replacement with genetically engineered mosquitoes to block its transmission is expected to become a new vector control strategy. The salivary glands are an effective target tissue for the expression of molecules that kill or inactivate malaria parasites. Moreover, salivary gland cells express a large number of molecules that facilitate blood feeding and parasite transmission to hosts. In the present study, we adapted a functional deficiency system in specific tissues by inducing cell death using the mouse Bcl-2-associated X protein (Bax) to the Asian malaria vector mosquito, Anopheles stephensi. We applied this technique to salivary gland cells, and produced a transgenic strain containing extremely low amounts of saliva. Although probing times for feeding on mice were longer in transgenic mosquitoes than in wild-type mosquitoes, transgenic mosquitoes still successfully ingested blood. Transgenic mosquitoes also exhibited a significant reduction in oocyst formation in the midgut in a rodent malaria model. These results indicate that mosquito saliva plays an important role in malaria infection in the midgut of anopheline mosquitoes. The dysfunction in the salivary glands enabled the inhibition of malaria transmission from hosts to mosquito midguts. Therefore, salivary components have potential in the development of new drugs or genetically engineered mosquitoes for malaria control. PMID:27598328

  7. Expression Profiles and RNAi Silencing of Inhibitor of Apoptosis Transcripts in Aedes, Anopheles, and Culex Mosquitoes (Diptera: Culicidae).

    PubMed

    Puglise, Jason M; Estep, Alden S; Becnel, James J

    2016-03-01

    Effective mosquito control is vital to curtail the devastating health effects of many vectored diseases. RNA interference (RNAi)-mediated control of mosquitoes is an attractive alternative to conventional chemical pesticides. Previous studies have suggested that transcripts for inhibitors of apoptosis (IAPs) may be good RNAi targets. To revisit and extend previous reports, we examined the expression of Aedes aegypti (L.) IAPs (AaeIAPs) 1, 2, 5, 6, 9, and a viral IAP-associated factor (vIAF) as well as Anopheles quadrimaculatus Say and Culex quinquefasciatus Say IAP1 homologs (AquIAP1 and CquIAP1) in adult females. Expression profiles of IAPs suggested that some older female mosquitoes had significantly higher IAP mRNA levels when compared to the youngest ones. Minor differences in expression of AaeIAPs were observed in mosquitoes that imbibed a bloodmeal, but the majority of the time points (up to 48 h) were not significantly different. Although in vitro experiments with the Ae. aegypti Aag-2 cell line demonstrated that the various AaeIAPs could be effectively knocked down within one day after dsRNA treatment, only Aag-2 cells treated with dsIAP1 displayed apoptotic morphology. Gene silencing and mortality were also evaluated after topical application and microinjection of the same dsRNAs into female Ae. aegypti. In contrast to previous reports, topical administration of dsRNA against AaeIAP1 did not yield a significant reduction in gene expression or increased mortality. Knockdown of IAP1 and other IAPs by microinjection did not result in significant mortality. In toto, our findings suggest that IAPs may not be suitable RNAi targets for controlling adult mosquito populations.

  8. Adult Vampire Bats Produce Contact Calls When Isolated: Acoustic Variation by Species, Population, Colony, and Individual

    PubMed Central

    Carter, Gerald G.; Logsdon, Ryane; Arnold, Bryan D.; Menchaca, Angelica; Medellin, Rodrigo A.

    2012-01-01

    Background Bat pups produce individually distinct isolation calls to facilitate maternal recognition. Increasing evidence suggests that, in group-living bat species, adults often use similar calls to maintain contact. We investigated if isolated adults from all three species of the highly cooperative vampire bats (Phyllostomidae: Desmodontinae) would produce vocally distinct contact calls when physically isolated. Methods/Principal Findings We assessed variation in contact calls recorded from isolated captive and wild-caught adult common vampire bats (Desmodus rotundus), white-winged vampire bats (Diaemus youngi) and hairy-legged vampire bats (Diphylla ecaudata). We compared species-typical contact call structure, and used information theory and permuted discriminate function analyses to examine call structure variation, and to determine if the individuality of contact calls is encoded by different call features across species and populations. We found that isolated adult vampire bats produce contact calls that vary by species, population, colony, and individual. However, much variation occurred within a single context and individual. We estimated signature information for captive Diaemus (same colony), captive Desmodus (same colony), and wild Desmodus (different colonies) at 3.21, 3.26, and 3.88 bits, respectively. Contact calls from a captive colony of Desmodus were less individually distinct than calls from wild-caught Desmodus from different colonies. Both the degree of individuality and parameters encoding individuality differed between the bats from a single captive colony and the wild-caught individuals from different groups. This result is consistent with, but not sufficient evidence of, vocal convergence in groups. Conclusion Our results show that adult vampire bats of all three species produce highly variable contact calls when isolated. Contact calls contain sufficient information for vocal discrimination, but also possess more intra-individual variation

  9. Point-Source and Area-Wide Field Studies of Pyriproxyfen Autodissemination Against Urban Container-Inhabiting Mosquitoes

    DTIC Science & Technology

    2014-04-05

    accumulation Pupal mortality Population density a b s t r a c t Autodissemination of insecticides is a novel strategy for mosquito...application to natural water bodies is prohibited in the US. The field evaluation of pyriproxyfen against mosquito larvae has shown longer persistence...public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Autodissemination of insecticides is a novel strategy for mosquito

  10. Efficacy of Two Common Methods of Application of Residual Insecticide for Controlling the Asian Tiger Mosquito, Aedes albopictus (Skuse), in Urban Areas

    PubMed Central

    Marini, Lorenzo; Baseggio, Alberto; Drago, Andrea; Martini, Simone; Manella, Paolo; Romi, Roberto; Mazzon, Luca

    2015-01-01

    After its first introduction in the 1980’s the Asian tiger mosquito, Aedes albopictus (Skuse), has spread throughout Southern Europe. Ae. albopictus is considered an epidemiologically important vector for the transmission of many viral pathogens such as the yellow fever virus, dengue fever and Chikungunya fever, as well as several filarial nematodes such as Dirofilaria immitis or D. repens. It is therefore crucial to develop measures to reduce the risks of disease transmission by controlling the vector populations. The aim of the study was to compare the efficacy of two application techniques (mist vs. stretcher sprayer) and two insecticides (Etox based on the nonester pyrethroid Etofenprox vs. Microsin based on the pyrethroid type II Cypermetrin) in controlling adult tiger mosquito populations in highly populated areas. To test the effect of the two treatments pre- and post-treatment human landing rate counts were conducted for two years. After one day from the treatment we observed a 100% population decrease in mosquito abundance with both application methods and both insecticides. However, seven and 14 days after the application the stretcher sprayer showed larger population reductions than the mist sprayer. No effect of insecticide type after one day and 14 days was found, while Etox caused slightly higher population reduction than Microsin after seven days. Emergency measures to locally reduce the vector populations should adopt adulticide treatments using stretcher sprayers. However, more research is still needed to evaluate the potential negative effects of adulticide applications on non-target organisms. PMID:26248028

  11. Anatomical variation of posterior slope of tibial plateau in adult Eastern Indian population

    PubMed Central

    Medda, Shyamalendu; Kundu, Rajib; Sengupta, Sohini; Pal, Ananda Kisor

    2017-01-01

    Background: Upper surface of the proximal tibial end, tibial plateau, has a slope directed posteroinferiorly relative to the long axis of the middle of the shaft. It has important consideration in surgeries such as knee arthroplasty, high tibial osteotomy, and medical imaging of the knee joint. The aim of the present study was to estimate the tibial plateau angle (TPA) by plain radiograph in the adult Eastern Indian population as during literature review, we were unable to find any study, except one (without specific reference axis), on this variable among the Indian population. Materials and Methods: A sample was taken from adult patients attending the outpatient department of orthopedics of the institute with minor knee problems. Measurement of the TPA was done in the true lateral radiographs of the knee joints of the selected subjects by a standardized method. Results: TPA varied widely from 6° to 24°, with the mean ± standard deviation value 13.6° ±3.5°. Student's unpaired t-test revealed no significant difference of TPA between left and right knees, both in male (P = 0.748) and female (P = 0.917) separately and in the entire study population irrespective of gender (P = 0.768). Comparison of TPA between male (13.3° ± 3.3°) and female (13.9° ± 3.4°) by Student's unpaired t-test showed no sexual dimorphism (P = 0.248). There were poor correlations of TPA with age and body mass index. Conclusion: The present study described the variations of the TPA in the adult Eastern Indian population (range 6°–24°, mean ± SD 13.6° ± 3.5°, no laterality, no sexual dimorphism, poor correlation with age and BMI). Knowledge of this study could be used in different orthopedic surgeries and imaging technique in or around the knee joint. PMID:28216753

  12. Fitness of anopheline mosquitoes expressing transgenes that inhibit Plasmodium development.

    PubMed

    Moreira, Luciano A; Wang, Jing; Collins, Frank H; Jacobs-Lorena, Marcelo

    2004-03-01

    One potential strategy for the control of malaria and other vector-borne diseases is the introduction into wild vector populations of genetic constructs that reduce vectorial capacity. An important caveat of this approach is that the genetic construct should have minimal fitness cost to the transformed vector. Previously, we produced transgenic Anopheles stephensi expressing either of two effector genes, a tetramer of the SM1 dodecapeptide or the phospholipase A2 gene (PLA2) from honeybee venom. Mosquitoes carrying either of these transgenes were impaired for Plasmodium berghei transmission. We have investigated the role of two effector genes for malaria parasite blockage in terms of the fitness imposed to the mosquito vector that expresses either molecule. By measuring mosquito survival, fecundity, fertility, and by running population cage experiments, we found that mosquitoes transformed with the SM1 construct showed no significant reduction in these fitness parameters relative to nontransgenic controls. The PLA2 transgenics, however, had reduced fitness that seemed to be independent of the insertion site of the transgene. We conclude that the fitness load imposed by refractory gene(s)-expressing mosquitoes depends on the effect of the transgenic protein produced in that mosquito. These results have important implications for implementation of malaria control via genetic modification of mosquitoes.

  13. The reproductive hormone cycle of adult female American alligators from a barrier island population.

    PubMed

    Hamlin, Heather J; Lowers, Russell H; Kohno, Satomi; Mitsui-Watanabe, Naoko; Amano, Haruna; Hara, Akihiko; Ohta, Yasuhiko; Miyagawa, Shinichi; Iguchi, Taisen; Guillette, Louis J

    2014-06-01

    Comparatively, little data are available detailing the geographic variation that exists in the reproductive endocrinology of adult alligators, especially those living in barrier islands. The Merritt Island National Wildlife Refuge (MI) is a unique barrier island environment and home to the Kennedy Space Center (FL, USA). Seasonal patterns of sex steroids were assessed in adult female American alligators from MI monthly from 2008 to 2009, with additional samples collected at more random intervals in 2006, 2007, and 2010. Plasma 17β-estradiol and vitellogenin concentrations peaked in April, coincident with courtship and mating, and showed patterns similar to those observed in adult female alligators in other regions. Plasma concentrations of progesterone, however, showed patterns distinctly different than those reported for alligator populations in other regions and remained relatively constant throughout the year. Plasma DHEA peaked in July around the time of oviposition, decreased in August, and then remained constant for the remaining months, except for a moderate increase in October. Circulating concentrations of DHEA have not been previously assessed in a female crocodilian, and plasma concentrations coincident with reproductive activity suggest a reproductive and/or behavioral role. Interestingly, plasma testosterone concentrations peaked in May of 2008, as has been shown in female alligator populations in other regions, but showed no peak in 2009, demonstrating dramatic variability from year to year. Surveys showed 2009 to be particularly depauperate of alligator nests in MI, and it is possible that testosterone could serve as a strong indicator of breeding success.

  14. Intricate predatory decisions by a mosquito-specialist spider from Malaysia

    PubMed Central

    Jackson, Robert R.; Li, Daiqin; Woon, Jeremy R. W.; Hashim, Rosli; Cross, Fiona R.

    2014-01-01

    Paracyrba wanlessi is a southeast Asian jumping spider (Salticidae) that lives in the hollow internodes of fallen bamboo and preys on the larvae, pupae and adults of mosquitoes. In contrast to Evarcha culicivora, an East African salticid that is also known for actively targeting mosquitoes as preferred prey, there was no evidence of P. wanlessi choosing mosquitoes on the basis of species, sex or diet. However, our findings show that P. wanlessi chooses mosquitoes significantly more often than a variety of other prey types, regardless of whether the prey are in or away from water, and regardless of whether the mosquitoes are adults or juveniles. Moreover, a preference for mosquito larvae, pupae and adults is expressed regardless of whether test spiders are maintained on a diet of terrestrial or aquatic prey and regardless of whether the diet includes or excludes mosquitoes. Congruence of an environmental factor (in water versus away from water) with prey type (aquatic versus terrestrial mosquitoes) appeared to be important and yet, even when the prey were in the incongruent environment, P. wanlessi continued to choose mosquitoes more often than other prey. PMID:26064534

  15. Intricate predatory decisions by a mosquito-specialist spider from Malaysia.

    PubMed

    Jackson, Robert R; Li, Daiqin; Woon, Jeremy R W; Hashim, Rosli; Cross, Fiona R

    2014-10-01

    Paracyrba wanlessi is a southeast Asian jumping spider (Salticidae) that lives in the hollow internodes of fallen bamboo and preys on the larvae, pupae and adults of mosquitoes. In contrast to Evarcha culicivora, an East African salticid that is also known for actively targeting mosquitoes as preferred prey, there was no evidence of P. wanlessi choosing mosquitoes on the basis of species, sex or diet. However, our findings show that P. wanlessi chooses mosquitoes significantly more often than a variety of other prey types, regardless of whether the prey are in or away from water, and regardless of whether the mosquitoes are adults or juveniles. Moreover, a preference for mosquito larvae, pupae and adults is expressed regardless of whether test spiders are maintained on a diet of terrestrial or aquatic prey and regardless of whether the diet includes or excludes mosquitoes. Congruence of an environmental factor (in water versus away from water) with prey type (aquatic versus terrestrial mosquitoes) appeared to be important and yet, even when the prey were in the incongruent environment, P. wanlessi continued to choose mosquitoes more often than other prey.

  16. Mosquito repellent activity of volatile oils from selected aromatic plants.

    PubMed

    Lalthazuali; Mathew, Nisha

    2017-02-01

    Essential oils from fresh leaves of four aromatic plants viz., Ocimum sanctum, Mentha piperita, Eucalyptus globulus and Plectranthus amboinicus were extracted by hydrodistillation. The test solutions were prepared as 20% essential oil in ethanol and positive control as 20% DEET in ethanol. Essential oil blend was prepared as 5% concentration. Nulliparous, 3-5-day-old female adult Aedes aegypti mosquitoes were used for repellency screening as per ICMR protocol. The study showed that the repellency of 20% essential oil of O. sanctum, M. piperita and P. amboinicus were comparable with that of the standard DEET (20%) as no mosquito landing on the test was observed up to 6 h. The E. globulus oil exhibited mosquito repellency only upto 1½ h. Considerable mosquito landing and feeding was displayed in negative control. In the case of the oil blend, no landing of mosquitoes was seen up to 6 h as that of positive control. The results showed that the essential oil blend from O. sanctum, M. piperita, E. globulus and P. amboinicus could repel Ae. aegypti mosquitoes or prevent from feeding as in the case of DEET even at a lower concentration of 5%. This study demonstrates the potential of essential oils from O. sanctum, M. piperita, E. globulus and P. amboinicus and their blend as mosquito repellents against Ae. aegypti, the vector of dengue, chikungunya and yellow fever.

  17. Urbanization Increases Aedes albopictus Larval Habitats and Accelerates Mosquito Development and Survivorship

    PubMed Central

    Li, Yiji; Kamara, Fatmata; Zhou, Guofa; Puthiyakunnon, Santhosh; Li, Chunyuan; Liu, Yanxia; Zhou, Yanhe; Yao, Lijie; Yan, Guiyun; Chen, Xiao-Guang

    2014-01-01

    Introduction Aedes albopictus is a very invasive and aggressive insect vector that causes outbreaks of dengue fever, chikungunya disease, and yellow fever in many countries. Vector ecology and disease epidemiology are strongly affected by environmental changes. Urbanization is a worldwide trend and is one of the most ecologically modifying phenomena. The purpose of this study is to determine how environmental changes due to urbanization affect the ecology of Aedes albopictus. Methods Aquatic habitats and Aedes albopictus larval population surveys were conducted from May to November 2013 in three areas representing rural, suburban, and urban settings in Guangzhou, China. Ae. albopictus adults were collected monthly using BG-Sentinel traps. Ae. albopictus larva and adult life-table experiments were conducted with 20 replicates in each of the three study areas. Results The urban area had the highest and the rural area had the lowest number of aquatic habitats that tested positive for Ae. albopictus larvae. Densities in the larval stages varied among the areas, but the urban area had almost two-fold higher densities in pupae and three-fold higher in adult populations compared with the suburban and rural areas. Larvae developed faster and the adult emergence rate was higher in the urban area than in suburban and rural areas. The survival time of adult mosquitoes was also longer in the urban area than it was in suburban and rural areas. Study regions, surface area, water depth, water clearance, surface type, and canopy coverage were important factors associated with the presence of Ae. albopictus larvae. Conclusions Urbanization substantially increased the density, larval development rate, and adult survival time of Ae. albopictus, which in turn potentially increased the vector capacity, and therefore, disease transmissibility. Mosquito ecology and its correlation with dengue virus transmission should be compared in different environmental settings. PMID:25393814

  18. Brackish water mosquito problem of Vypeen Island, Cochin, Kerala.

    PubMed

    Mariappan, T; Arunachalam, N; Reddy, C M; Sabesan, S; Panicker, K N

    1996-03-01

    A preliminary study has shown that the marshy terrain and brackish water bodies associated with mangrove forests contributed profuse breeding of mosquitos in Vypeen island, causing a severe menace to the island population. A total of 14 species belonging to four genera viz, Aedes, Anopheles, Armigeres and Culex was recorded from different habitats. Culex sitiens was found to be the predominant mosquito in all the perennial breeding habitats. The extent of different habitats in the production of mosquitos, and its possible abatement, using environmental and/or biocontrol methods are discussed.

  19. A Review of Dietary Surveys in the Adult South African Population from 2000 to 2015.

    PubMed

    Mchiza, Zandile J; Steyn, Nelia P; Hill, Jillian; Kruger, Annamarie; Schönfeldt, Hettie; Nel, Johanna; Wentzel-Viljoen, Edelweiss

    2015-09-23

    One serious concern of health policymakers in South Africa is the fact that there is no national data on the dietary intake of adult South Africans. The only national dietary study was done in children in 1999. Hence, it becomes difficult to plan intervention and strategies to combat malnutrition without national data on adults. The current review consequently assessed all dietary studies in adults from 2000 to June 2015 in an attempt to portray typical adult dietary intakes and to assess possible dietary deficiencies. Notable findings were that, in South Africa micronutrient deficiencies are still highly prevalent and energy intakes varied between very low intakes in informal settlements to very high intakes in urban centers. The most commonly deficient food groups observed are fruit and vegetables, and dairy. This has been attributed to high prices and lack of availability of these food groups in poorer urban areas and townships. In rural areas, access to healthy foods also remains a problem. A national nutrition monitoring system is recommended in order to identify dietary deficiencies in specific population groups.

  20. A Review of Dietary Surveys in the Adult South African Population from 2000 to 2015

    PubMed Central

    Mchiza, Zandile J.; Steyn, Nelia P.; Hill, Jillian; Kruger, Annamarie; Schönfeldt, Hettie; Nel, Johanna; Wentzel-Viljoen, Edelweiss

    2015-01-01

    One serious concern of health policymakers in South Africa is the fact that there is no national data on the dietary intake of adult South Africans. The only national dietary study was done in children in 1999. Hence, it becomes difficult to plan intervention and strategies to combat malnutrition without national data on adults. The current review consequently assessed all dietary studies in adults from 2000 to June 2015 in an attempt to portray typical adult dietary intakes and to assess possible dietary deficiencies. Notable findings were that, in South Africa micronutrient deficiencies are still highly prevalent and energy intakes varied between very low intakes in informal settlements to very high intakes in urban centers. The most commonly deficient food groups observed are fruit and vegetables, and dairy. This has been attributed to high prices and lack of availability of these food groups in poorer urban areas and townships. In rural areas, access to healthy foods also remains a problem. A national nutrition monitoring system is recommended in order to identify dietary deficiencies in specific population groups. PMID:26404371

  1. Genetic architecture differences between pediatric and adult-onset inflammatory bowel diseases in the Polish population

    PubMed Central

    Ostrowski, Jerzy; Paziewska, Agnieszka; Lazowska, Izabella; Ambrozkiewicz, Filip; Goryca, Krzysztof; Kulecka, Maria; Rawa, Tomasz; Karczmarski, Jakub; Dabrowska, Michalina; Zeber-Lubecka, Natalia; Tomecki, Roman; Kluska, Anna; Balabas, Aneta; Piatkowska, Magdalena; Paczkowska, Katarzyna; Kierkus, Jaroslaw; Socha, Piotr; Lodyga, Michal; Rydzewska, Grazyna; Klopocka, Maria; Mierzwa, Grazyna; Iwanczak, Barbara; Krzesiek, Elzbieta; Bak-Drabik, Katarzyna; Walkowiak, Jaroslaw; Klincewicz, Beata; Radwan, Piotr; Grzybowska-Chlebowczyk, Urszula; Landowski, Piotr; Jankowska, Agnieszka; Korczowski, Bartosz; Starzynska, Teresa; Albrecht, Piotr; Mikula, Michal

    2016-01-01

    Most inflammatory bowel diseases (IBDs) are classic complex disorders represented by common alleles. Here we aimed to define the genetic architecture of pediatric and adult-onset IBDs for the Polish population. A total of 1495 patients were recruited, including 761 patients with Crohn’s disease (CD; 424 pediatric), 734 patients with ulcerative colitis (UC; 390 pediatric), and 934 healthy controls. Allelotyping employed a pooled-DNA genome-wide association study (GWAS) and was validated by individual genotyping. Whole exome sequencing (WES) was performed on 44 IBD patients diagnosed before 6 years of age, 45 patients diagnosed after 40 years of age, and 18 healthy controls. Altogether, out of 88 selected SNPs, 31 SNPs were replicated for association with IBD. A novel BRD2 (rs1049526) association reached significance of P = 5.2 × 10−11 and odds ratio (OR) = 2.43. Twenty SNPs were shared between pediatric and adult patients; 1 and 7 were unique to adult-onset and pediatric-onset IBD, respectively. WES identified numerous rare and potentially deleterious variants in IBD-associated or innate immunity-associated genes. Deleterious alleles in both groups were over-represented among rare variants in affected children. Our GWAS revealed differences in the polygenic architecture of pediatric- and adult-onset IBD. A significant accumulation of rare and deleterious variants in affected children suggests a contribution by yet unexplained genetic components. PMID:28008999

  2. Does covering of farm-associated Culicoides larval habitat reduce adult populations in the United Kingdom?

    PubMed

    Harrup, L E; Gubbins, S; Barber, J; Denison, E; Mellor, P S; Purse, B V; Carpenter, S

    2014-03-17

    Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of a range of internationally important arboviruses of livestock, including bluetongue virus (BTV) and the recently emerging Schmallenberg virus (SBV). Culicoides species in the subgenus Avaritia (in the UK: Culicoides obsoletus Meigen, Culicoides scoticus Downes & Kettle, Culicoides dewulfi Goetghebuer and Culicoides chiopterus Meigen) have been implicated in BTV transmission in northern Europe and to a varying degree utilise cattle dung as a larval development substrate. The collection of cattle dung into heaps on farms provides a localised source of Culicoides emergence in close proximity to livestock. This study assesses the impact of covering dung heaps prior to the onset of adult Culicoides activity with the aim of reducing recruitment to the local adult populations at four livestock farms in England. Light suction trap catches of adult Culicoides from these farms were compared with those from four untreated control farms from a wide geographic range across the UK. It was demonstrated that implementing control of emergence from dung heaps did not have a significant impact upon the local adult subgenus Avaritia abundance at the treated farm holdings and that the onset of Culicoides activity was similarly unaffected. Use of this method in isolation is unlikely to have an effect in reducing the risk of BTV and SBV transmission. The implications of these results for control of farm-associated Culicoides in Europe are discussed.

  3. Larval diet affects mosquito development and permissiveness to Plasmodium infection

    PubMed Central

    Linenberg, Inbar; Christophides, George K.; Gendrin, Mathilde

    2016-01-01

    The larval stages of malaria vector mosquitoes develop in water pools, feeding mostly on microorganisms and environmental detritus. Richness in the nutrient supply to larvae influences the development and metabolism of larvae and adults. Here, we investigated the effects of larval diet on the development, microbiota content and permissiveness to Plasmodium of Anopheles coluzzii. We tested three fish diets often used to rear mosquitoes in the laboratory, including two pelleted diets, Dr. Clarke’s Pool Pellets and Nishikoi Fish Pellets, and one flaked diet, Tetramin Fish-Flakes. Larvae grow and develop faster and produce bigger adults when feeding on both types of pellets compared with flakes. This correlates with a higher microbiota load in pellet-fed larvae, in agreement with the known positive effect of the microbiota on mosquito development. Larval diet also significantly influences the prevalence and intensity of Plasmodium berghei infection in adults, whereby Nishikoi Fish Pellets-fed larvae develop into adults that are highly permissive to parasites and survive longer after infection. This correlates with a lower amount of Enterobacteriaceae in the midgut microbiota. Together, our results shed light on the influence of larval feeding on mosquito development, microbiota and vector competence; they also provide useful data for mosquito rearing. PMID:27910908

  4. Estimating malaria transmission from humans to mosquitoes in a noisy landscape.

    PubMed

    Reiner, Robert C; Guerra, Carlos; Donnelly, Martin J; Bousema, Teun; Drakeley, Chris; Smith, David L

    2015-10-06

    A basic quantitative understanding of malaria transmission requires measuring the probability a mosquito becomes infected after feeding on a human. Parasite prevalence in mosquitoes is highly age-dependent, and the unknown age-structure of fluctuating mosquito populations impedes estimation. Here, we simulate mosquito infection dynamics, where mosquito recruitment is modelled seasonally with fractional Brownian noise, and we develop methods for estimating mosquito infection rates. We find that noise introduces bias, but the magnitude of the bias depends on the 'colour' of the noise. Some of these problems can be overcome by increasing the sampling frequency, but estimates of transmission rates (and estimated reductions in transmission) are most accurate and precise if they combine parity, oocyst rates and sporozoite rates. These studies provide a basis for evaluating the adequacy of various entomological sampling procedures for measuring malaria parasite transmission from humans to mosquitoes and for evaluating the direct transmission-blocking effects of a vaccine.

  5. Estimating malaria transmission from humans to mosquitoes in a noisy landscape

    PubMed Central

    Reiner, Robert C.; Guerra, Carlos; Donnelly, Martin J.; Bousema, Teun; Drakeley, Chris; Smith, David L.

    2015-01-01

    A basic quantitative understanding of malaria transmission requires measuring the probability a mosquito becomes infected after feeding on a human. Parasite prevalence in mosquitoes is highly age-dependent, and the unknown age-structure of fluctuating mosquito populations impedes estimation. Here, we simulate mosquito infection dynamics, where mosquito recruitment is modelled seasonally with fractional Brownian noise, and we develop methods for estimating mosquito infection rates. We find that noise introduces bias, but the magnitude of the bias depends on the ‘colour' of the noise. Some of these problems can be overcome by increasing the sampling frequency, but estimates of transmission rates (and estimated reductions in transmission) are most accurate and precise if they combine parity, oocyst rates and sporozoite rates. These studies provide a basis for evaluating the adequacy of various entomological sampling procedures for measuring malaria parasite transmission from humans to mosquitoes and for evaluating the direct transmission-blocking effects of a vaccine. PMID:26400195

  6. Pesticide-Free Device a Fatal Attraction for Mosquitoes

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Are those pesky mosquitoes getting more entertainment out of your family picnic than you are? If the answer is yes, then it is time to reclaim your backyard with assistance from an unlikely partner. Nowadays, NASA is developing tools to track and predict the spread of the West Nile Virus on a global scale, but several years ago, the Space Agency carved out some time to collaborate with an outdoor products manufacturer in order to help control mosquito populations on a local level. The technology resulting from this union leveraged a space-age heat blanket to attract mosquitoes, which would then be eliminated without the use of harmful pesticides or chemicals. technical assistance from NASA and is an environmentally safe way to reduce the mosquito population.

  7. Biological Control Strategies for Mosquito Vectors of Arboviruses

    PubMed Central

    Huang, Yan-Jang S.; Higgs, Stephen; Vanlandingham, Dana L.

    2017-01-01

    Historically, biological control utilizes predatory species and pathogenic microorganisms to reduce the population of mosquitoes as disease vectors. This is particularly important for the control of mosquito-borne arboviruses, which normally do not have specific antiviral therapies available. Although development of resistance is likely, the advantages of biological control are that the resources used are typically biodegradable and ecologically friendly. Over the past decade, the advancement of molecular biology has enabled optimization by the manipulation of genetic materials associated with biological control agents. Two significant advancements are the discovery of cytoplasmic incompatibility induced by Wolbachia bacteria, which has enhanced replacement programs, and the introduction of dominant lethal genes into local mosquito populations through the release of genetically modified mosquitoes. As various arboviruses continue to be significant public health threats, biological control strategies have evolved to be more diverse and become critical tools to reduce the disease burden of arboviruses. PMID:28208639

  8. A national cross-sectional survey of dental anxiety in the French adult population

    PubMed Central

    Nicolas, Emmanuel; Collado, Valérie; Faulks, Denise; Bullier, Brigitte; Hennequin, Martine

    2007-01-01

    Background Dental anxiety is a public health problem but no epidemiological study has been undertaken in France to evaluate its prevalence. The aim of this study was to estimate the prevalence, severity and associations of dental anxiety in a sample of the French adult population. Methods A convenience sample of 2725 adults (mean age = 47 years, SD16, minimum = 16, maximum = 101 years), representative of the French population with regard to age and urban distribution, completed a French version of the Corah Dental Anxiety scale (DAS) and a questionnaire relating to their dental appointments. Results Moderate dental anxiety (14≥DAS≥13) was revealed for 172 persons (6.2%), while 195 (7.3%) had severe dental anxiety (DAS≥15), giving an overall prevalence of dental anxiety of 13.5%. Prevalence was lower proportionally with age (P < 0.001) and was higher in French overseas territories and in the countryside (P < 0.01). Farmers and low skilled workers were significantly more anxious than executives and shopkeepers (P < 0.001). Anxiety was associated with avoidance of care (p < 0.001) and lack of regular dental appointments (p < 0.001). Conclusion Dental anxiety in France appears to concern a similar proportion of the population as in other industrialised European, Australasian or North American countries. Recommendations for prevention and management of dental anxiety are made with reference to dental education and health care services in France. PMID:17927808

  9. Prevalence, Awareness, Treatment, and Control of Hypertension among Saudi Adult Population: A National Survey

    PubMed Central

    Saeed, Abdalla A.; Al-Hamdan, Nasser A.; Bahnassy, Ahmed A.; Abdalla, Abdelshakour M.; Abbas, Mostafa A. F.; Abuzaid, Lamiaa Z.

    2011-01-01

    This cross-sectional study aimed at estimating prevalence, awareness, treatment, control, and predictors of hypertension among Saudi adult population. Multistage stratified sampling was used to select 4758 adult participants. Three blood pressure measurements using an automatic sphygmomanometer, sociodemographics, and antihypertensive modalities were obtained. The overall prevalence of hypertension was 25.5%. Only 44.7% of hypertensives were aware, 71.8% of them received pharmacotherapy, and only 37.0% were controlled. Awareness was significantly associated with gender, age, geographical location, occupation, and comorbidity. Applying drug treatment was significantly more among older patients, but control was significantly higher among younger patients and patients with higher level of physical activity. Significant predictors of hypertension included male gender, urbanization, low education, low physical activity, obesity, diabetes, and hypercholesterolemia. In conclusion prevalence is high, but awareness, treatment, and control levels are low indicating a need to develop a national program for prevention, early detection, and control of hypertension. PMID:21912737

  10. Malpighian Tubules as Novel Targets for Mosquito Control

    PubMed Central

    Piermarini, Peter M.; Esquivel, Carlos J.; Denton, Jerod S.

    2017-01-01

    The Malpighian tubules and hindgut are the renal excretory tissues of mosquitoes; they are essential to maintaining hemolymph water and solute homeostasis. Moreover, they make important contributions to detoxifying metabolic wastes and xenobiotics in the hemolymph. We have focused on elucidating the molecular mechanisms of Malpighian tubule function in adult female mosquitoes and developing chemical tools as prototypes for next-generation mosquitocides that would act via a novel mechanism of action (i.e., renal failure). To date, we have targeted inward rectifier potassium (Kir) channels expressed in the Malpighian tubules of the yellow fever mosquito Aedes aegypti and malaria mosquito Anopheles gambiae. Inhibition of these channels with small molecules inhibits transepithelial K+ and fluid secretion in Malpighian tubules, leading to a disruption of hemolymph K+ and fluid homeostasis in adult female mosquitoes. In addition, we have used next-generation sequencing to characterize the transcriptome of Malpighian tubules in the Asian tiger mosquito Aedes albopictus, before and after blood meals, to reveal new molecular targets for potentially disrupting Malpighian tubule function. Within 24 h after a blood meal, the Malpighian tubules enhance the mRNA expression of genes encoding mechanisms involved with the detoxification of metabolic wastes produced during blood digestion (e.g., heme, NH3, reactive oxygen species). The development of chemical tools targeting these molecular mechanisms in Malpighian tubules may offer a promising avenue for the development of mosquitocides that are highly-selective against hematophagous females, which are the only life stage that transmits pathogens. PMID:28125032

  11. Taxonomic Separation of Hippocampal Networks: Principal Cell Populations and Adult Neurogenesis

    PubMed Central

    van Dijk, R. Maarten; Huang, Shih-Hui; Slomianka, Lutz; Amrein, Irmgard

    2016-01-01

    While many differences in hippocampal anatomy have been described between species, it is typically not clear if they are specific to a particular species and related to functional requirements or if they are shared by species of larger taxonomic units. Without such information, it is difficult to infer how anatomical differences may impact on hippocampal function, because multiple taxonomic levels need to be considered to associate behavioral and anatomical changes. To provide information on anatomical changes within and across taxonomic ranks, we present a quantitative assessment of hippocampal principal cell populations in 20 species or strain groups, with emphasis on rodents, the taxonomic group that provides most animals used in laboratory research. Of special interest is the importance of adult hippocampal neurogenesis (AHN) in species-specific adaptations relative to other cell populations. Correspondence analysis of cell numbers shows that across taxonomic units, phylogenetically related species cluster together, sharing similar proportions of principal cell populations. CA3 and hilus are strong separators that place rodent species into a tight cluster based on their relatively large CA3 and small hilus while non-rodent species (including humans and non-human primates) are placed on the opposite side of the spectrum. Hilus and CA3 are also separators within rodents, with a very large CA3 and rather small hilar cell populations separating mole-rats from other rodents that, in turn, are separated from each other by smaller changes in the proportions of CA1 and granule cells. When adult neurogenesis is included, the relatively small populations of young neurons, proliferating cells and hilar neurons become main drivers of taxonomic separation within rodents. The observations provide challenges to the computational modeling of hippocampal function, suggest differences in the organization of hippocampal information streams in rodent and non-rodent species, and

  12. Contents of cesium, iodine, strontium, thorium, and uranium in selected human organs of adult asian population.

    PubMed

    Iyengar, G V; Kawamura, H; Dang, H S; Parr, R M; Wang, J W; Cho, S Y; Natera, E S

    2004-08-01

    Contents of cesium, iodine, strontium, thorium, and uranium in some selected human organs were estimated for adult Asian population using data obtained in four Asian countries: China, India, Philippines, and Republic of Korea, as part of a Coordinated Research Program of the International Atomic Energy Agency on "Ingestion and Organ contents of elements of importance in radiation protection." These countries together represent more than 40% of the world population. Highly sensitive analytical techniques were employed to measure cesium in skeletal muscle, iodine in thyroid, strontium in skeleton, thorium and uranium in skeleton, liver, kidneys, and lungs where, in comparison to other organs, these elements are present in higher concentrations. The organ contents for adult Asian population, when compared with the corresponding data proposed for Reference Man by International Commission on Radiological Protection (ICRP), showed about 40 times lower kidneys content and about 10 times lower skeleton content of uranium. The content of thorium in skeleton for Asian population was also half of the ICRP Reference Man value. Interestingly, organ contents for the other elements such as iodine in thyroid, cesium in skeletal muscle, and strontium in skeleton were comparable for Asian and the Caucasian population (represented by ICRP Reference Man). Organ contents for these elements were also calculated by applying the new ICRP models of these elements to their daily intakes. The comparison of the calculated and measured organ contents showed that despite uncertainties in the organ content values arising due to the inter-country variations in daily dietary intakes, the contents were within a factor of two to three. This observation is significant since human data both on organ contents and ingestion were obtained at environmental level of intakes. The study suggests that currently available ICRP models for these elements are quite realistic.

  13. TSH levels are associated with vitamin D status and seasonality in an adult population of euthyroid adults.

    PubMed

    Barchetta, I; Baroni, M G; Leonetti, F; De Bernardinis, M; Bertoccini, L; Fontana, M; Mazzei, E; Fraioli, A; Cavallo, M G

    2015-08-01

    A circannual periodicity in thyrotropin (TSH) secretion has been reported but the causes of these phenomenon are still undefined. Vitamin D exerts a direct influence on pituitary axes including the hypothalamus-pituitary-thyroid axis. Aims of the present study were to investigate the presence of a seasonal variability of TSH secretion and to study the association between vitamin D status and TSH levels in a population of euthyroid adults. For this purpose, we recruited 294 euthyroid adults (M/F 133/161, 48.5 ± 12.4 years). Study participants underwent clinical examination and routine biochemistry assessment. Vitamin D deficiency was diagnosed for serum 25(OH) vitamin D <25 nmol/l. Significantly higher TSH levels were found in subjects who underwent blood sampling during the Autumn-Winter compared with individuals evaluated in Spring-Summer (2.3 ± 1.3 vs. 1.8 ± 1.1 μIU/ml, p = 0.03). Vitamin D deficiency was strongly associated with higher TSH levels (p = 0.01) after adjusting for sex, age, and sample's season. Although vitamin D deficiency was also associated with metabolic syndrome and its components, the association between TSH levels and vitamin D status persisted also considering these confounders. These data reveal the occurrence of seasonal variability of serum TSH concentration in euthyroid subjects and provide evidence for the first time that an association exists between vitamin D status and serum TSH levels.

  14. Association between Polyphenol Intake and Hypertension in Adults and Older Adults: A Population-Based Study in Brazil

    PubMed Central

    Miranda, Andreia Machado; Steluti, Josiane; Fisberg, Regina Mara; Marchioni, Dirce Maria

    2016-01-01

    Background/Objective Hypertension is an important risk factor for cardiovascular disease, and diet has been identified as a modifiable factor for preventing and controlling hypertension. Besides, epidemiological studies have suggested an inverse association between polyphenol intake and cardiovascular diseases. The aim of this study was to evaluate the association between the intake of polyphenols and hypertension in a general population of Sao Paulo. Methods Data came from the ‘Health Survey of Sao Paulo (ISA-Capital)’ among 550 adults and older adults in Sao Paulo, Brazil. Diet was assessed by two 24-hour dietary recalls (24HR). Usual intakes were calculated using the Multiple Source Method. Polyphenol intake was calculated by matching food consumption data from the 24HR with the Phenol-Explorer database. The associations between the hypertension and tertiles of the total and classes of polyphenols intake were tested by multivariate logistic regression analysis. Results After multivariate adjustment for potential confounding factors the findings showed an inverse and linearly association between the hypertension and highest tertiles of tyrosols (OR = 0.33; 95%CI 0.18, 0.64), alkylphenols (OR = 0.45; 95%CI 0.23, 0.87), lignans (OR = 0.49; 95%CI 0.25, 0.98), as well as stilbenes (OR = 0.60; 95%CI 0.36, 0.98), and other polyphenols (OR = 0.33; 95%CI 0.14, 0.74). However, total polyphenol intake, and phenolic acids were significantly associated only in the middle tertile with hypertension and flavonoids were not significant associated. Conclusion There is an inverse and linearly association between the highest tertile of some classes of polyphenols, such as, tyrosols, alkylphenols, lignans, stilbenes, other polyphenols and hypertension. PMID:27792767

  15. Road-Traffic Noise: Annoyance, Risk Perception, and Noise Sensitivity in the Finnish Adult Population

    PubMed Central

    Okokon, Enembe Oku; Turunen, Anu W.; Ung-Lanki, Sari; Vartiainen, Anna-Kaisa; Tiittanen, Pekka; Lanki, Timo

    2015-01-01

    Exposure to road-traffic noise commonly engenders annoyance, the extent of which is determined by factors not fully understood. Our aim was to estimate the prevalence and determinants of road-traffic noise annoyance and noise sensitivity in the Finnish adult population, while comparing the perceptions of road-traffic noise to exhausts as environmental health problems. Using a questionnaire that yielded responses from 1112 randomly selected adult Finnish respondents, we estimated road-traffic noise- and exhausts-related perceived exposures, health-risk perceptions, and self-reported annoyance on five-point scales, while noise sensitivity estimates were based on four questions. Determinants of noise annoyance and sensitivity were investigated using multivariate binary logistic regression and linear regression models, respectively. High or extreme noise annoyance was reported by 17% of respondents. Noise sensitivity scores approximated a Gaussian distribution. Road-traffic noise and exhausts were, respectively, considered high or extreme population-health risks by 22% and 27% of respondents. Knowledge of health risks from traffic noise, OR: 2.04 (1.09–3.82) and noise sensitivity, OR: 1.07 (1.00–1.14) were positively associated with annoyance. Knowledge of health risks (p < 0.045) and positive environmental attitudes (p < 000) were associated with higher noise sensitivity. Age and sex were associated with annoyance and sensitivity only in bivariate models. A considerable proportion of Finnish adults are highly annoyed by road-traffic noise, and perceive it to be a significant health risk, almost comparable to traffic exhausts. There is no distinct noise-sensitive population subgroup. Knowledge of health risks of road-traffic noise, and attitudinal variables are associated with noise annoyance and sensitivity. PMID:26016432

  16. Road-traffic noise: annoyance, risk perception, and noise sensitivity in the Finnish adult population.

    PubMed

    Okokon, Enembe Oku; Turunen, Anu W; Ung-Lanki, Sari; Vartiainen, Anna-Kaisa; Tiittanen, Pekka; Lanki, Timo

    2015-05-26

    Exposure to road-traffic noise commonly engenders annoyance, the extent of which is determined by factors not fully understood. Our aim was to estimate the prevalence and determinants of road-traffic noise annoyance and noise sensitivity in the Finnish adult population, while comparing the perceptions of road-traffic noise to exhausts as environmental health problems. Using a questionnaire that yielded responses from 1112 randomly selected adult Finnish respondents, we estimated road-traffic noise- and exhausts-related perceived exposures, health-risk perceptions, and self-reported annoyance on five-point scales, while noise sensitivity estimates were based on four questions. Determinants of noise annoyance and sensitivity were investigated using multivariate binary logistic regression and linear regression models, respectively. High or extreme noise annoyance was reported by 17% of respondents. Noise sensitivity scores approximated a Gaussian distribution. Road-traffic noise and exhausts were, respectively, considered high or extreme population-health risks by 22% and 27% of respondents. Knowledge of health risks from traffic noise, OR: 2.04 (1.09-3.82) and noise sensitivity, OR: 1.07 (1.00-1.14) were positively associated with annoyance. Knowledge of health risks (p<0.045) and positive environmental attitudes (p<000) were associated with higher noise sensitivity. Age and sex were associated with annoyance and sensitivity only in bivariate models. A considerable proportion of Finnish adults are highly annoyed by road-traffic noise, and perceive it to be a significant health risk, almost comparable to traffic exhausts. There is no distinct noise-sensitive population subgroup. Knowledge of health risks of road-traffic noise, and attitudinal variables are associated with noise annoyance and sensitivity.

  17. The Contributions of Phonological and Morphological Awareness to Literacy Skills In the Adult Basic Education Population

    PubMed Central

    Fracasso, Lucille E.; Bangs, Kathryn; Binder, Katherine S.

    2014-01-01

    The Adult Basic Education (ABE) population consists of a wide range of abilities with needs that may be unique to this set of learners. The purpose of this study was to better understand the relative contributions of phonological decoding and morphological awareness to spelling, vocabulary, and comprehension across a sample of ABE students. In this study, phonological decoding was a unique predictor of spelling ability, listening comprehension and reading comprehension. We also found that morphological awareness was a unique predictor of spelling ability, vocabulary, and listening comprehension. Morphological awareness indirectly contributed to reading comprehension through vocabulary. These findings suggest the need for morphological interventions for this group of learners. PMID:24935886

  18. Potential for mosquitoes (Diptera: Culicidae) from Florida to transmit rift valley fever virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We evaluated 8 species of mosquitoes collected in Florida to determine which of these should be targeted for control should Rift Valley fever virus (RVFV) be detected in North America. Female mosquitoes that had fed on adult hamsters inoculated with RVFV were incubated for 7-21 d at 26°C, allowed to...

  19. Field and Laboratory Evaluation of Bioefficacy of an Insect Growth Regulator (Dimilin) as a Larvicide against Mosquito and Housefly Larvae

    PubMed Central

    Msangi, Shandala; Lyatuu, Ester; Kweka, Eliningaya J.

    2011-01-01

    The inhibitory function of Dimilin (Diflubenzuron), mostly a chitin synthesis regulator, on the ecdysis of mosquitoes (Anopheles gambiae s.l., Culex quinquefasciatus) and housefly was evaluated in the field and in laboratory. Three formulations of Diflubenzuron were evaluated in this study: Dimilin, Wettable powder (25%), Dimilin granules (2%), and Dimilin tablets (2%). The laboratory and field evaluation used different rates of concentrations of these formulations. Generally, at higher dosages larvae developments, eggs hatchability and pupation were impossible. The development of mosquitoes was significantly higher in control while highly depressed in different dosages of treatment in both laboratory and field experiments. In houseflies, the adult population decreased sharply after treatment of their breeding sites while pupae mortality was noticed to be high in laboratory-treated samples. Dimilin could be opted as one of the choice of the larval control chemicals to be incorporated in the integrated vector control programmes in urban and rural areas. PMID:21941567

  20. Morphometric Wing Characters as a Tool for Mosquito Identification

    PubMed Central

    Christe, Rafael de Oliveira; Multini, Laura Cristina; Vidal, Paloma Oliveira; Wilk-da-Silva, Ramon; de Carvalho, Gabriela Cristina; Marrelli, Mauro Toledo

    2016-01-01

    Mosquitoes are responsible for the transmission of important infectious diseases, causing millions of deaths every year and endangering approximately 3 billion people around the world. As such, precise identification of mosquito species is crucial for an understanding of epidemiological patterns of disease transmission. Currently, the most common method of mosquito identification relies on morphological taxonomic keys, which do not always distinguish cryptic species. However, wing geometric morphometrics is a promising tool for the identification of vector mosquitoes, sibling and cryptic species included. This study therefore sought to accurately identify mosquito species from the three most epidemiologically important mosquito genera using wing morphometrics. Twelve mosquito species from three epidemiologically important genera (Aedes, Anopheles and Culex) were collected and identified by taxonomic keys. Next, the right wing of each adult female mosquito was removed and photographed, and the coordinates of eighteen digitized landmarks at the intersections of wing veins were collected. The allometric influence was assessed, and canonical variate analysis and thin-plate splines were used for species identification. Cross-validated reclassification tests were performed for each individual, and a Neighbor Joining tree was constructed to illustrate species segregation patterns. The analyses were carried out and the graphs plotted with TpsUtil 1.29, TpsRelw 1.39, MorphoJ 1.02 and Past 2.17c. Canonical variate analysis for Aedes, Anopheles and Culex genera showed three clear clusters in morphospace, correctly distinguishing the three mosquito genera, and pairwise cross-validated reclassification resulted in at least 99% accuracy; subgenera were also identified correctly with a mean accuracy of 96%, and in 88 of the 132 possible comparisons, species were identified with 100% accuracy after the data was subjected to reclassification. Our results showed that Aedes, Culex

  1. Sources of error in the estimation of mosquito infection rates used to assess risk of arbovirus transmission.

    PubMed

    Bustamante, Dulce M; Lord, Cynthia C

    2010-06-01

    Infection rate is an estimate of the prevalence of arbovirus infection in a mosquito population. It is assumed that when infection rate increases, the risk of arbovirus transmission to humans and animals also increases. We examined some of the factors that can invalidate this assumption. First, we used a model to illustrate how the proportion of mosquitoes capable of virus transmission, or infectious, is not a constant fraction of the number of infected mosquitoes. Thus, infection rate is not always a straightforward indicator of risk. Second, we used a model that simulated the process of mosquito sampling, pooling, and virus testing and found that mosquito infection rates commonly underestimate the prevalence of arbovirus infection in a mosquito population. Infection rate should always be used in conjunction with other surveillance indicators (mosquito population size, age structure, weather) and historical baseline data when assessing the risk of arbovirus transmission.

  2. Population-specific consequences of fisheries-related stressors on adult sockeye salmon.

    PubMed

    Donaldson, M R; Hinch, S G; Raby, G D; Patterson, D A; Farrell, A P; Cooke, S J

    2012-01-01

    The objective of this study was to determine whether fisheries-related stressors differently influence two populations of adult sockeye salmon (Oncorhynchus nerka) with shared migration timing and location but where one population (i.e., Harrison) spawns 1 mo after the other (i.e., Weaver). Four stressor treatments were used following beach seine capture: (1) immediate release, (2) release after 10-15 min in the beach seine, (3) an additional 3-min gill net entanglement and 1-min air exposure, and (4) an additional 3-min tangle net simulation and 1-min air exposure. A comprehensive acoustic telemetry array and manual tracking revealed that survival was low overall, with more Weaver fish (34.2% of 38 tagged) reaching spawning areas compared to Harrison fish (17.8% of 78 tagged). For the Harrison population but not the Weaver, the gill net treatment influenced immediate (i.e., survived treatment) and short-term (i.e., 5-d postrelease) survival as well as survival to reach spawning areas. Harrison fish were more likely to be injured by the treatment, and reflex impairment predicted their short-term and long-term survival. Physiological condition did not differ between populations at the time of release, although both populations showed signs of severe physiological disturbances from the gill and tangle net simulations. These results suggest that even short durations of gill or tangle net entanglement can result in profound population-specific physiological disturbances and mortality. The notion that there can be population-specific variation in response to fisheries encounters adds complexity to management and provides further evidence for intraspecific differences in migration success.

  3. Complementary and Alternative Medicine Use in the US Adult Low Back Pain Population

    PubMed Central

    Johnson, Pamela Jo; Evans, Roni L.; Kreitzer, Mary Jo

    2016-01-01

    Background: Many people suffering from low back pain (LBP) have found conventional medical treatments to be ineffective for managing their LBP and are increasingly turning to complementary and alternative medicine (CAM) to find pain relief. A comprehensive picture of CAM use in the LBP population, including all of the most commonly used modalities, is needed. Study Objective: To examine prevalence and perceived benefit of CAM use within the US LBP population by limiting vs nonlimiting LBP and to evaluate the odds of past year CAM use within the LBP population Methods: Data are from the 2012 National Health Interview Survey, Alternative Health Supplement. We examined a nationally representative sample of US adults with LBP (N=9665 unweighted). Multiple logistic regression was used to estimate the odds of past year CAM use. Results: In all, 41.2% of the LBP population used CAM in the past year, with higher use reported among those with limiting LBP. The most popular therapies used in the LBP population included herbal supplements, chiropractic manipulation, and massage. The majority of the LBP population used CAM specifically to treat back pain, and 58.1% of those who used CAM for their back pain perceived a great deal of benefit. Conclusion: The results are indicative of CAM becoming an increasingly important component of care for people with LBP. Additional understanding of patterns of CAM use among the LBP population will help health professionals make more informed care decisions and guide investigators in development of future back pain–related CAM research. PMID:26937316

  4. An insight into the sialotranscriptome of the non-blood feeding Toxorhynchites amboinensis mosquito

    PubMed Central

    Calvo, E.; Pham, V. M.; Ribeiro, J. M. C.

    2008-01-01

    All adult mosquitoes take sugar meals, and most adult females also take blood meals to develop eggs. Salivary glands (SG) of males are thus much smaller and do not contain many of the antihemostatic and antiinflammatory compounds found in females. In the past 5 years, transcriptome analyses have identified nearly 70 different genes expressed in adult female SG. For most of these, no function can be assigned in either blood or sugar feeding. Exceptionally, Toxorhynchites mosquitoes are unusual in that they never feed on blood, and the SG of adults are identical in both sexes. Transcriptome analysis of the adult SG of this mosquito was performed to increase knowledge of the evolution of blood feeding—and to identify polypeptide families associated with sugar feeding—in mosquitoes. PMID:18405828

  5. Psychosocial Factors Associated with Diet Quality in a Working Adult Population

    PubMed Central

    Dunbar, Sandra B.; Higgins, Melinda; Dai, Jun; Ziegler, Thomas R.; Frediani, Jennifer K.; Reilly, Carolyn; Brigham, Kenneth L.

    2014-01-01

    The associations between specific intra- and inter-personal psychosocial factors and dietary patterns were explored in a healthy, working adult population. Participants (N= 640) were enrolled in a prospective predictive health study and characterized by a mean age of 48(SD = 11) years, 67% women, and 30% minority. Baseline psychosocial measures of perceived stress, depressive symptoms, social support, and family functioning were examined for their relationships with three diet quality indices - AHEI, DASH, and the Mediterranean. Dietary intake was of moderate quality in this high income, well-educated, psychosocially healthy population. Social support was positively associated with better diet quality for all three indices (p< .01). Further research should focus on socio-environmental factors associated with diet quality. PMID:23408456

  6. Unipotent, Atoh1+ progenitors maintain the Merkel cell population in embryonic and adult mice.

    PubMed

    Wright, Margaret C; Reed-Geaghan, Erin G; Bolock, Alexa M; Fujiyama, Tomoyuki; Hoshino, Mikio; Maricich, Stephen M

    2015-02-02

    Resident progenitor cells in mammalian skin generate new cells as a part of tissue homeostasis. We sought to identify the progenitors of Merkel cells, a unique skin cell type that plays critical roles in mechanosensation. We found that some Atoh1-expressing cells in the hairy skin and whisker follicles are mitotically active at embryonic and postnatal ages. Genetic fate-mapping revealed that these Atoh1-expressing cells give rise solely to Merkel cells. Furthermore, selective ablation of Atoh1(+) skin cells in adult mice led to a permanent reduction in Merkel cell numbers, demonstrating that other stem cell populations are incapable of producing Merkel cells. These data identify a novel, unipotent progenitor population in the skin that gives rise to Merkel cells both during development and adulthood.

  7. Public perception of mosquito annoyance measured by a survey and simultaneous mosquito sampling.

    PubMed

    Read, N R; Rooker, J R; Gathman, J P

    1994-03-01

    For randomly chosen residents of the Minneapolis-St. Paul, Minnesota, metropolitan area, survey responses, reported bites, and observed defensive behaviors (e.g., brushing, swatting) for a 5-min period in their yard were compared with simultaneous mosquito counts from a human-baited drop-net trap 6 m from the resident. When mosquitoes trapped, reported bites, or observed behaviors per 5 min were 3 or more, the majority of respondents described the mosquito levels as greater than "moderate" and anticipated reduced outdoor time and/or possible repellent use. At 25 or more mosquitoes trapped, 11 or more reported bites, or 16 or more observed behaviors per 5 min, response was "bad", with most people anticipating a major reduction in outdoor time (without repellent), "probably" or "definitely" planning to use repellent, and anticipating some outdoor time loss even if using repellent. Levels of less than 3 mosquitoes trapped per 5 min were related to moderate annoyance in 20-45% of the population. Individual response was highly variable, and the personal and environmental covariates measured did not account for more than half the variability.

  8. Pyrethroid resistance in Aedes aegypti and Aedes albopictus: Important mosquito vectors of human diseases.

    PubMed

    Smith, Letícia B; Kasai, Shinji; Scott, Jeffrey G

    2016-10-01

    Aedes aegypti and A. albopictus mosquitoes are vectors of important human disease viruses, including dengue, yellow fever, chikungunya and Zika. Pyrethroid insecticides are widely used to control adult Aedes mosquitoes, especially during disease outbreaks. Herein, we review the status of pyrethroid resistance in A. aegypti and A. albopictus, mechanisms of resistance, fitness costs associated with resistance alleles and provide suggestions for future research. The widespread use of pyrethroids has given rise to many populations with varying levels of resistance worldwide, albeit with substantial geographical variation. In adult A. aegypti and A. albopictus, resistance levels are generally lower in Asia, Africa and the USA, and higher in Latin America, although there are exceptions. Susceptible populations still exist in several areas of the world, particularly in Asia and South America. Resistance to pyrethroids in larvae is also geographically widespread. The two major mechanisms of pyrethroid resistance are increased detoxification due to P450-monooxygenases, and mutations in the voltage sensitive sodium channel (Vssc) gene. Several P450s have been putatively associated with insecticide resistance, but the specific P450s involved are not fully elucidated. Pyrethroid resistance can be due to single mutations or combinations of mutations in Vssc. The presence of multiple Vssc mutations can lead to extremely high levels of resistance. Suggestions for future research needs are presented.

  9. General Information about Mosquitoes

    EPA Pesticide Factsheets

    There are about 200 different species of mosquitoes in the U. S., with varied habitats and behaviors. Bites can transmit diseases such as malaria and West Nile virus to humans, as well as diseases and parasites particularly harmful to dogs and horses.

  10. Fighting Arbovirus Transmission: Natural and Engineered Control of Vector Competence in Aedes Mosquitoes

    PubMed Central

    Kean, Joy; Rainey, Stephanie M.; McFarlane, Melanie; Donald, Claire L.; Schnettler, Esther; Kohl, Alain; Pondeville, Emilie

    2015-01-01

    Control of aedine mosquito vectors, either by mosquito population reduction or replacement with refractory mosquitoes, may play an essential role in the fight against arboviral diseases. In this review, we will focus on the development and application of biological approaches, both natural or engineered, to limit mosquito vector competence for arboviruses. The study of mosquito antiviral immunity has led to the identification of a number of host response mechanisms and proteins that are required to control arbovirus replication in mosquitoes, though more factors influencing vector competence are likely to be discovered. We will discuss key aspects of these pathways as targets either for selection of naturally resistant mosquito populations or for mosquito genetic manipulation. Moreover, we will consider the use of endosymbiotic bacteria such as Wolbachia, which in some cases have proven to be remarkably efficient in disrupting arbovirus transmission by mosquitoes, but also the use of naturally occurring insect-specific viruses that may interfere with arboviruses in mosquito vectors. Finally, we will discuss the use of paratransgenesis as well as entomopathogenic fungi, which are also proposed strategies to control vector competence. PMID:26463078

  11. Fighting Arbovirus Transmission: Natural and Engineered Control of Vector Competence in Aedes Mosquitoes.

    PubMed

    Kean, Joy; Rainey, Stephanie M; McFarlane, Melanie; Donald, Claire L; Schnettler, Esther; Kohl, Alain; Pondeville, Emilie

    2015-03-23

    Control of aedine mosquito vectors, either by mosquito population reduction or replacement with refractory mosquitoes, may play an essential role in the fight against arboviral diseases. In this review, we will focus on the development and application of biological approaches, both natural or engineered, to limit mosquito vector competence for arboviruses. The study of mosquito antiviral immunity has led to the identification of a number of host response mechanisms and proteins that are required to control arbovirus replication in mosquitoes, though more factors influencing vector competence are likely to be discovered. We will discuss key aspects of these pathways as targets either for selection of naturally resistant mosquito populations or for mosquito genetic manipulation. Moreover, we will consider the use of endosymbiotic bacteria such as Wolbachia, which in some cases have proven to be remarkably efficient in disrupting arbovirus transmission by mosquitoes, but also the use of naturally occurring insect-specific viruses that may interfere with arboviruses in mosquito vectors. Finally, we will discuss the use of paratransgenesis as well as entomopathogenic fungi, which are also proposed strategies to control vector competence.

  12. Suppressor T-cell population induced by Junin virus in adult mice.

    PubMed Central

    Campetella, O E; Barrios, H A; Galassi, N V

    1988-01-01

    Intracerebral (i.c.) Junin virus (JV) infection of adult BALB/c mice is characterized by the absence of morbidity and a low mortality (barely 8-10%). In contrast, the suckling mouse model exhibits almost 100% mortality following central nervous system (CNS) alterations consistent with a delayed-type hypersensitivity (DTH)-like immune response. Besides, JV infection of adult (resistant) mice leads to immunosuppression of DTH to unrelated antigens. Here we present evidence demonstrating that such suppression is mediated by JV-induced cells present in spleen from 24 hr to 24 days post-infection, bearing the Thy-1+, Ly-1+2- phenotype and reactive to an unrelated antigen such as sheep red blood cells (SRBC). No evidence of suppressor factors was found. A relatively low number of total splenic cells (5 x 10(6) cells/mouse) was enough to transfer suppression. Therefore, this cell population may be involved in adult mouse survival to JV infection. PMID:2970429

  13. A Population Pharmacokinetic Approach to Describe Cephalexin Disposition in Adult and Aged Dogs

    PubMed Central

    Prados, Ana Paula; Kreil, Verónica; Monfrinotti, Agustina; Quaine, Pamela; Tarragona, Lisa; Hallu, Ruben

    2014-01-01

    This study was conducted in order to characterize the pharmacokinetics of orally administered cephalexin to healthy adult and aged dogs, using a population pharmacokinetic approach. Two hundred and eighty-six cephalexin plasma concentrations obtained from previous pharmacokinetic studies were used. Sex, age, pharmaceutical formulation, and breed were evaluated as covariates. A one-compartment model with an absorption lag-time (Tlag) best described the data. The final model included age (adult; aged) on apparent volume of distribution (Vd/F), apparent elimination rate (ke/F), and Tlag; sex (female; male) on ke/F, and breed (Beagle; mixed-breed) on Vd/F. Addition of the covariates to the model explained 78% of the interindividal variability (IIV) in Vd/F, 36% in ke/F, and 24% in Tlag, respectively. Formulation did not affect the variability of any of the pharmacokinetic parameters. Tlag was longer, whereas Vd/F and ke/F were lower in aged compared to adult animals; in female aged dogs ke/F was lower than in male aged dogs; however, the differences were of low magnitude. Different disposition of cephalexin may be expected in aged dogs. PMID:25431741

  14. Reduction of mosquito biting-pressure: spatial repellents or mosquito traps? A field comparison of seven commercially available products in Israel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The personal protection capability of seven commercially available mosquito control devices (MCD) is compared under field conditions in Israel. Trials were performed in a high biting-pressure area inhabited by large populations of mosquito and biting midge species and using human volunteers for lan...

  15. Larval Population Density Alters Adult Sleep in Wild-Type Drosophila melanogaster but Not in Amnesiac Mutant Flies.

    PubMed

    Chi, Michael W; Griffith, Leslie C; Vecsey, Christopher G

    2014-08-11

    Sleep has many important biological functions, but how sleep is regulated remains poorly understood. In humans, social isolation and other stressors early in life can disrupt adult sleep. In fruit flies housed at different population densities during early adulthood, social enrichment was shown to increase subsequent sleep, but it is unknown if population density during early development can also influence adult sleep. To answer this question, we maintained Drosophila larvae at a range of population densities throughout larval development, kept them isolated during early adulthood, and then tested their sleep patterns. Our findings reveal that flies that had been isolated as larvae had more fragmented sleep than those that had been raised at higher population densities. This effect was more prominent in females than in males. Larval population density did not affect sleep in female flies that were mutant for amnesiac, which has been shown to be required for normal memory consolidation, adult sleep regulation, and brain development. In contrast, larval population density effects on sleep persisted in female flies lacking the olfactory receptor or83b, suggesting that olfactory signals are not required for the effects of larval population density on adult sleep. These findings show that population density during early development can alter sleep behavior in adulthood, suggesting that genetic and/or structural changes are induced by this developmental manipulation that persist through metamorphosis.

  16. Survivorship of Hip and Knee Implants in Pediatric and Young Adult Populations

    PubMed Central

    Sedrakyan, Art; Romero, Lucas; Graves, Stephen; Davidson, David; de Steiger, Richard; Lewis, Peter; Solomon, Michael; Vial, Robyn; Lorimer, Michelle

    2014-01-01

    Background: One of the least researched areas in orthopaedic pediatrics is the safety and effectiveness of joint replacement, in part because it is uncommon and is undertaken for a wide range of conditions not common for adult joint replacement. This study used data from the AOANJRR (Australian Orthopaedic Association National Joint Replacement Registry) to analyze the use of total hip arthroplasty (THA) and total knee arthroplasty (TKA) in the pediatric population and to provide preliminary data on the outcome of these procedures. Methods: The AOANJRR, which is part of the ICOR (International Consortium of Orthopaedic Registries), provided information on pediatric procedures reported to the registry by hospitals undertaking arthroplasty procedures in Australia. All THA and TKA procedures reported to the registry from 1999 to 2012 were included. The cumulative percent revision and the hazard ratio from Cox proportional-hazards models were used for analysis. All tests were two-tailed, with a 5% level of significance. Additionally, an overview of the literature is presented to provide a point of reference. Results: Primary conventional THA was performed in 297 patients twenty years of age or younger; the cumulative percent revision at five years was 4.5%. Primary conventional THA was performed in 975 young adults twenty-one to thirty years of age; the cumulative percent revision at five years was 5.4%. Primary THA was performed in 105 patients twenty years of age or younger; the cumulative percent revision at five years was 4.6%. Primary TKA was performed in 159 young adults twenty-one to thirty years of age; the cumulative percent revision at five years was 10.3%. Conclusions: Compared with older adults, pediatric patients and young adults undergoing THA and TKA have very different diagnoses, including a high prevalence of tumor. Although the reported rate of revision surgery is currently similar to that for older patients, the number of reported procedures and the

  17. Adult Celiac Disease: Patients Are Shorter Compared with Their Peers in the General Population

    PubMed Central

    Esmaeilzadeh, Abbas; Ganji, Azita; Goshayeshi, Ladan; Ghafarzadegan, Kamran; Afzal Aghayee, Mehdi; Mosanen Mozafari, Homan; Saadatniya, Hassan; Hayatbakhs, Abdolrasol; Ghavami Ghanbarabadi, Vahid

    2016-01-01

    BACKGROUND Delay in diagnosis of celiac disease (CD) occurs frequently, although its consequences are mostly not known. One of the presented symptoms in pediatric patients with CD is the short stature. However, far too little attention has been paid to physical features including height of adult patients with CD. This study was undertaken to evaluate whether patients suffering from CD are shorter in comparison with the general population without CD. As well, we evaluated probable correlations between demographic and physical features, main complains, serum anti tTG level, and intestinal pathology damage between short (lower quartile) versus tall stature (upper quartile) patients with CD. METHODS This was a retrospective cross-sectional study on 219 adult patients diagnosed as having CD in the Celiac Disease Center, between June 2008 and June 2014 in Mashhad, Iran. The exclusion criteria were ages less than 18 and more than 60 years. Height was compared with a group of 657 age- and sex matched control cases from the healthy population. The probable influencing factors on height such as intestinal pathology, serum level of anti-tissue transglutaminase(anti-tTG), serum vitamin D, and hemoglobin level at the time of diagnosis were assessed and were compared in short (lower quartile) versus tall stature (upper quartile) patients with CD. RESULTS Both male (n=65) and female (n=154) patients with CD were shorter than their counterpart in the general population (males: 168.5±8.6 to 171.3±7.2cm, p <0.01 and females: 154.8±10.58 to 157.8±7.2 cm, p <0.01). Spearman linear correlation showed height in patient with CD was correlated with serum hemoglobin (p <0.001, r=0.285) and bone mineral density (p<0.001) and not with serum vitamin D levels (p =0.024, r=0.237), but was not correlated with anti-tTG serum levels (p=0.97). CD patients with upper and lower quartile of height in men and women had no significant difference in the anti-tTG level and degree of duodenal pathology

  18. Dental prosthetic status and treatment needs of adult population in Jizan, Saudi Arabia: A survey report

    PubMed Central

    Peeran, Syed Ali; Al Sanabani, Fuad; AL-Makramani, Bandar M. A.; Elamin, Elfatih Ibrahim

    2016-01-01

    Objectives: The study aimed to evaluate and compare the dental prosthetic status and treatment needs of adult population in Jizan, Saudi Arabia, in relation to the age. Materials and Methods: A total of 1779 people aged 35–74 years from 4 survey areas (Hay al matar, Mahata khams, Dara ut tawhid, and Suq ad dakhili) selected through convenient sampling, around Jizan University, were surveyed, using the WHO survey criteria, 1997. Statistical Analysis: Number and percentages were calculated, and univariate analysis was performed using Chi-square test at 5% level of significance. Results: Different forms of prosthesis were present among patients in the upper (19.9%) and lower (19%) arches, respectively. Prosthetic treatment need was recognized in subjects, 56.4% for the upper and 57.2% for the lower arches, respectively. The prosthetic status and treatment needs differed statistically with respect to age. Conclusion: More than half of the surveyed adult populations were in need of some or the other forms of prosthesis. This study provides data for an oral health-care provider program for Jizan. PMID:28042258

  19. Composition and Genetic Diversity of Mosquitoes (Diptera: Culicidae) on Islands and Mainland Shores of Kenya's Lakes Victoria and Baringo.

    PubMed

    Ajamma, Yvonne Ukamaka; Villinger, Jandouwe; Omondi, David; Salifu, Daisy; Onchuru, Thomas Ogao; Njoroge, Laban; Muigai, Anne W T; Masiga, Daniel K

    2016-11-01

    The Lake Baringo and Lake Victoria regions of Kenya are associated with high seroprevalence of mosquito-transmitted arboviruses. However, molecular identification of potential mosquito vector species, including morphologically identified ones, remains scarce. To estimate the diversity, abundance, and distribution of mosquito vectors on the mainland shores and adjacent inhabited islands in these regions, we collected and morphologically identified adult and immature mosquitoes and obtained the corresponding sequence variation at cytochrome c oxidase 1 (COI) and internal transcribed spacer region 2 (ITS2) gene regions. A total of 63 species (including five subspecies) were collected from both study areas, 47 of which have previously been implicated as disease vectors. Fourteen species were found only on island sites, which are rarely included in mosquito diversity surveys. We collected more mosquitoes, yet with lower species composition, at Lake Baringo (40,229 mosquitoes, 32 species) than at Lake Victoria (22,393 mosquitoes, 54 species). Phylogenetic analysis of COI gene sequences revealed Culex perexiguus and Cx tenagius that could not be distinguished morphologically. Most Culex species clustered into a heterogeneous clade with closely related sequences, while Culex pipiens clustered into two distinct COI and ITS2 clades. These data suggest limitations in current morphological identification keys. This is the first DNA barcode report of Kenyan mosquitoes. To improve mosquito species identification, morphological identifications should be supported by their molecular data, while diversity surveys should target both adults and immatures. The diversity of native mosquito disease vectors identified in this study impacts disease transmission risks to humans and livestock.

  20. Clustering and combining pattern of metabolic syndrome components in a rural Brazilian adult population.

    PubMed

    Pimenta, Adriano Marçal; Felisbino-Mendes, Mariana Santos; Velasquez-Melendez, Gustavo

    2013-01-01

    CONTEXT AND OBJECTIVE Metabolic syndrome is characterized by clustering of cardiovascular risk factors such as obesity, dyslipidemia, insulin resistance, hyperinsulinemia, glucose intolerance and arterial hypertension. The aim of this study was to estimate the probability of clustering and the combination pattern of three or more metabolic syndrome components in a rural Brazilian adult population. DESIGN AND SETTING This was a cross-sectional study conducted in two rural communities located in the Jequitinhonha Valley, Minas Gerais, Brazil. METHODS The sample was composed of 534 adults (both sexes). Waist circumference, blood pressure and demographic, lifestyle and biochemical characteristics were assessed. The prevalences of metabolic syndrome and its components were estimated using the definitions of the National Cholesterol Education Program - Adult