117 research outputs found

    Enzootic Arbovirus Surveillance in Forest Habitat and Phylogenetic Characterization of Novel Isolates of Gamboa Virus in Panama

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    Landscape changes occurring in Panama, a country whose geographic location and climate have historically supported arbovirus transmission, prompted the hypothesis that arbovirus prevalence increases with degradation of tropical forest habitats. Investigations at four variably degraded sites revealed a diverse array of potential mosquito vectors, several of which are known vectors of arbovirus pathogens. Overall, 675 pools consisting of 25,787 mosquitoes and representing 29 species from nine genera (collected at ground and canopy height across all habitats) were screened for cytopathic viruses on Vero cells. We detected four isolates of Gamboa virus (family: Bunyaviridae; genus: Orthobunyavirus) from pools of Aedeomyia squamipennis captured at canopy level in November 2012. Phylogenetic characterization of complete genome sequences shows the new isolates to be closely related to each other with strong evidence of reassortment among the M segment of Panamanian Gamboa isolates and several other viruses of this group. At the site yielding viruses, Soberanía National Park in central Panama, 18 mosquito species were identified, and the predominant taxa included A. squamipennis, Coquillettidia nigricans, and Mansonia titillans.Landscape changes occurring in Panama, a country whose geographic location and climate have historically supported arbovirus transmission, prompted the hypothesis that arbovirus prevalence increases with degradation of tropical forest habitats. Investigations at four variably degraded sites revealed a diverse array of potential mosquito vectors, several of which are known vectors of arbovirus pathogens. Overall, 675 pools consisting of 25,787 mosquitoes and representing 29 species from nine genera (collected at ground and canopy height across all habitats) were screened for cytopathic viruses on Vero cells. We detected four isolates of Gamboa virus (family: Bunyaviridae; genus: Orthobunyavirus) from pools of Aedeomyia squamipennis captured at canopy level in November 2012. Phylogenetic characterization of complete genome sequences shows the new isolates to be closely related to each other with strong evidence of reassortment among the M segment of Panamanian Gamboa isolates and several other viruses of this group. At the site yielding viruses, Soberanía National Park in central Panama, 18 mosquito species were identified, and the predominant taxa included A. squamipennis, Coquillettidia nigricans, and Mansonia titillans

    Short Report: Anopheles darlingi (Diptera: Culicidae) in Panama

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    We report Anopheles darlingi in Darien Province in eastern Panama. Polymerase chain reaction–restriction fragment length polymorphism profiles of the single copy nuclear white gene and sequence comparisons confirmed the presence of 66 specimens of the northern lineage of An. darlingi . The parsimony network depicted 5 CO1 haplotypes in 40 specimens of An. darlingi , which connected through 7–8 mutational steps with sequences from Central and South America. Furthermore, the presence of haplotypes in Biroquera, Darien Province identical to those previously published from northern Colombia suggests that Panamanian samples originated in Colombia. Results of neutrality tests ( R 2 and Fu’s F S ) were not significant and the mismatch distribution was multimodal and did not fit the model of sudden population growth. These findings may indicate a long and stable presence of An. darlingi in eastern Panama.We report Anopheles darlingi in Darien Province in eastern Panama. Polymerase chain reaction–restriction fragment length polymorphism profiles of the single copy nuclear white gene and sequence comparisons confirmed the presence of 66 specimens of the northern lineage of An. darlingi . The parsimony network depicted 5 CO1 haplotypes in 40 specimens of An. darlingi , which connected through 7–8 mutational steps with sequences from Central and South America. Furthermore, the presence of haplotypes in Biroquera, Darien Province identical to those previously published from northern Colombia suggests that Panamanian samples originated in Colombia. Results of neutrality tests ( R 2 and Fu’s F S ) were not significant and the mismatch distribution was multimodal and did not fit the model of sudden population growth. These findings may indicate a long and stable presence of An. darlingi in eastern Panama

    Forest disturbance and vector transmitted diseases in thelowland tropical rainforest of central Panama

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    objective To explore possible changes in the community attributes of haematophagous insects as afunction of forest disturbance. We compare the patterns of diversity and abundance, plus thebehavioural responses of three epidemiologically distinct vector assemblages across sites depictingvarious levels of forest cover.methods Over a 3-year period, we sampled mosquitoes, sandflies and biting-midges in forestedhabitats of central Panama. We placed CDC light traps in the forest canopy and in the understorey togather blood-seeking females.results We collected 168 405 adult haematophagous dipterans in total, including 26 genera and 86species. Pristine forest settings were always more taxonomically diverse than the disturbed forest sites,confirming that disturbance has a negative impact on species richness. Species of Phlebotominae andCulicoides were mainly classified as climax (i.e. forest specialist) or disturbance-generalist, which tendto decrease in abundance along with rising levels of disturbance. In contrast, a significant portion ofmosquito species, including primary and secondary disease vectors, was classified as colonists (i.e.disturbed-areas specialists), which tend to increase in numbers towards more disturbed forest habitats.At pristine forest, the most prevalent species of Phlebotominae and Culicoides partitioned the verticalniche by being active at the forest canopy or in the understorey; yet this pattern was less clear indisturbed habitats. Most mosquito species were not vertically stratified in their habitat preference.conclusion We posit that entomological risk and related pathogen exposure to humans is higher inpristine forest scenarios for Culicoides and Phlebotominae transmitted diseases, whereas forestdisturbance poses a higher entomological risk for mosquito-borne infections. This suggests that theDilution Effect Hypothesis (DEH) does not apply in tropical rainforests where highly abundant, yetunrecognised insect vectors and neglected zoonotic diseases occur. Comprehensive, community levelentomological surveillance is, therefore, the key for predicting potential disease spill over in scenariosof pristine forest intermixed with anthropogenic habitats. We suggest that changes in forest qualityshould also be considered when assessing arthropod-borne disease transmission risk.objective To explore possible changes in the community attributes of haematophagous insects as afunction of forest disturbance. We compare the patterns of diversity and abundance, plus thebehavioural responses of three epidemiologically distinct vector assemblages across sites depictingvarious levels of forest cover.methods Over a 3-year period, we sampled mosquitoes, sandflies and biting-midges in forestedhabitats of central Panama. We placed CDC light traps in the forest canopy and in the understorey togather blood-seeking females.results We collected 168 405 adult haematophagous dipterans in total, including 26 genera and 86species. Pristine forest settings were always more taxonomically diverse than the disturbed forest sites,confirming that disturbance has a negative impact on species richness. Species of Phlebotominae andCulicoides were mainly classified as climax (i.e. forest specialist) or disturbance-generalist, which tendto decrease in abundance along with rising levels of disturbance. In contrast, a significant portion ofmosquito species, including primary and secondary disease vectors, was classified as colonists (i.e.disturbed-areas specialists), which tend to increase in numbers towards more disturbed forest habitats.At pristine forest, the most prevalent species of Phlebotominae and Culicoides partitioned the verticalniche by being active at the forest canopy or in the understorey; yet this pattern was less clear indisturbed habitats. Most mosquito species were not vertically stratified in their habitat preference.conclusion We posit that entomological risk and related pathogen exposure to humans is higher inpristine forest scenarios for Culicoides and Phlebotominae transmitted diseases, whereas forestdisturbance poses a higher entomological risk for mosquito-borne infections. This suggests that theDilution Effect Hypothesis (DEH) does not apply in tropical rainforests where highly abundant, yetunrecognised insect vectors and neglected zoonotic diseases occur. Comprehensive, community levelentomological surveillance is, therefore, the key for predicting potential disease spill over in scenariosof pristine forest intermixed with anthropogenic habitats. We suggest that changes in forest qualityshould also be considered when assessing arthropod-borne disease transmission risk

    Price and income policies

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    Discussion and objective debate is an important and necessary ingredient of social decision-making in a democracy. Only thus can the public, legislators, administrators and special interest groups inventory and understand the complete range of phenomena relevant for public decision. Discussion and analysis is a method of measurement, for a more complete inventory of goals and sub-goals of public policy and for expression of hypotheses and predictions in respect to outcomes of various policy means. Discussion is the most ancient and universal process for reasoned calculation in social policy, whether this be at the program committee of the 4-H Club or in presidential elections.https://lib.dr.iastate.edu/card_reports/1006/thumbnail.jp

    Mercury toxicity in livers of northern pike (Esox lucius) from Isle Royale, USA

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    Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology 147 (2008): 331-338, doi:10.1016/j.cbpc.2007.12.003.Many laboratory studies have documented that mercury can be toxic to fish, but it is largely unknown if mercury is toxic to fish in their natural environments. The objective of our study was to investigate the toxic effects of mercury on northern pike (Esox lucius) at Isle Royale, Michigan. In 124 northern pike from eight inland lakes, concentrations of total mercury in skin-on fillets ranged from 0.069 to 0.622 µg/g wet wt. Concentrations of total mercury in livers increased exponentially compared with concentrations in fillets, to a maximum of 3.1 µg/g wet wt. Methylmercury constituted a majority of the mercury in livers with total mercury concentrations <0.5 µg/g wet wt, but declined to 28-51% of the mercury in livers with total mercury concentrations >0.5 µg/g wet wt. Liver color (absorbance at 400 nm) varied among northern pike and was positively related to liver total mercury concentration. The pigment causing variation in liver color was identified as lipofuscin, which results from lipid peroxidation of membranous organelles. An analysis of covariance revealed lipofuscin accumulation was primarily associated with mercury exposure, and this association obscured any normal accumulation from aging. We also documented decreased lipid reserves in livers and poor condition factors of northern pike with high liver total mercury concentrations. Our results suggest (i) northern pike at Isle Royale are experiencing toxicity at concentrations of total mercury common for northern pike and other piscivorous fish elsewhere in North America and (ii) liver color may be useful for indicating mercury exposure and effects in northern pike at Isle Royale and possibly other aquatic ecosystems and other fish species.Financial support was provided by the U.S. Environmental Protection Agency STAR Graduate Fellowship Program to P.E.D

    Mercury flux to sediments of Lake Tahoe, California-Nevada

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    Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Water, Air, & Soil Pollution 210 (2010): 399-407, doi:10.1007/s11270-009-0262-y.We report estimates of mercury (Hg) flux to the sediments of Lake Tahoe, California-Nevada: 2 and 15-20 µg/m2/yr in preindustrial and modern sediments, respectively. These values result in a modern to preindustrial flux ratio of 7.5-10, which is similar to flux ratios recently reported for other alpine lakes in California, and greater than the value of 3 typically seen worldwide. We offer plausible hypotheses to explain the high flux ratios, including (1) proportionally less photoreduction and evasion of Hg with the onset of cultural eutrophication and (2) a combination of enhanced regional oxidation of gaseous elemental Hg and transport of the resulting reactive gaseous Hg to the surface with nightly downslope flows of air. If either of these mechanisms is correct, it could lead to local/regional solutions to lessen the impact of globally increasing anthropogenic emissions of Hg on Lake Tahoe and other alpine ecosystems.Funding was provided by Miami University, EPA-STAR, the Postdoctoral Scholar Program at Woods Hole Oceanographic Institution, and the USGS

    Exploring key-stakeholder perceptions on non-communicable disease care during the COVID-19 pandemic in Kenya

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    Introduction: over one third of total Disability-Adjusted-Life-Years lost in Kenya are due to non-communicable diseases (NCD). In response, the Government declared significant commitment towards improving NCD care. The COVID-19 pandemic increased the burden on the already overstretched health systems in Kenya. The aims of this study are to assess whether health care providers perceived NCD care to be optimal during the pandemic and explore how to improve responses to future emergencies. Methods: this cross-sectional online survey included healthcare personnel with non-clinical roles (public health workers and policy-makers) and those delivering health care (doctors and nurses). Respondents were recruited between May and September 2021 by random sampling, completed by snowball sampling. Results: among 236 participants (42% in clinical, 58% in non-clinical roles) there was an overall consensus between respondents on NCD care being disrupted and compromised during the pandemic in Kenya. Detracted supplies, funding, and technical resources affected the continuity of NCDs’ response, despite government efforts. Respondents agreed that the enhanced personnel capacity and competencies to manage COVID-19 patients were positive, but noted a lack of guidance for redirecting care for chronic diseases, and advocated for digital innovation as a solution. Conclusion: this paper explores the perceptions of key stakeholders involved in the management of NCDs in Kenya to improve planning for future emergency responses. Gaps were identified in health system response and preparedness capacity during the pandemic including the perceived need to strengthen NCD services, with solutions offered to guide resilience efforts to protect the health system from disruption

    Patterns of spatial and temporal variability of UV transparency in Lake Tahoe, California-Nevada

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    Lake Tahoe is an ultra-oligotrophic subalpine lake that is renowned for its clarity. The region experiences little cloud cover and is one of the most UV transparent lakes in the world. As such, it is an ideal environment to study the role of UV radiation in aquatic ecosystems. Long-term trends in Secchi depths showed that water transparency to visible light has decreased in recent decades, but limited data are available on the UV transparency of the lake. Here we examine how ultraviolet radiation varies relative to longer-wavelength photosynthetically active radiation (PAR, 400-700 nm, visible wavelengths) horizontally along inshore-offshore transects in the lake and vertically within the water column as well as temporally throughout 2007. UV transparency was more variable than PAR transparency horizontally across the lake and throughout the year. Seasonal patterns of Secchi transparency differed from both UV and PAR, indicating that different substances may be responsible for controlling transparency to UV, PAR, and Secchi. In surface waters, UVA (380 nm) often attenuated more slowly than PAR, a pattern visible in only exceptionally transparent waters with very low dissolved organic carbon. On many sampling dates, UV transparency decreased progressively with depth suggesting surface photobleaching, reductions in particulate matter, increasing chlorophyll a, or some combination of these increased during summer months. Combining these patterns of UV transparency with data on visible light provides a more comprehensive understanding of ecosystem structure, function, and effects of environmental change in highly transparent alpine and subalpine lakes such as Tahoe

    Children's at Home: Pilot Study Assessing Dedicated Social Media for Parents of Adolescents with Neurofibromatosis Type 1.

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    The aim of this pilot study was to evaluate Children's at Home (C@H), a dedicated social media website for parents of adolescents with neurofibromatosis type 1 (NF1). The interventional study included two phases: (1) creating video intervention/prevention assessment (VIA) visual narratives about having an adolescent with NF1 and (2) interacting on C@H, a secure, medically moderated social media website. C@H was evaluated qualitatively at three time points. At enrollment (T0, N = 17), participants reported needing C@H to break their isolation, connect with other families, and receive accurate information, advice, and support from others facing similar challenges. At T1, after creating VIA during 6 months (N = 13, 145 videos), participants mostly valued the opportunity to speak about the challenges they face with NF1 and their journey since diagnosis. At T2, after interacting on C@H for 7 weeks (N = 10, two sign-ins/week/parent), participants reported connecting with other parents of children with NF1 for the first time, valuing the "real faces" and emotions of other parents with shared experiences providing a sense of normalcy. Qualitative analysis suggested that C@H decreased feelings of isolation, provided relief to talk about NF1 without having to explain it, provided new knowledge about NF1 and the opportunity to address non-medical issues of NF1 never discussed in clinic, and helped participants with putting their lives into perspective. C@H allowed parents of adolescents with NF1 to overcome previous isolation and connect for the first time. Innovative applications of social media dedicated to those who care for children with chronic conditions can provide peer-to-peer support, shared experience, and reliable medical information
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