Scholarly Works, Population Health Sciences

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  • Raising an Eye at Facial Muscle Morphology in Canids
    Sexton, Courtney L.; Diogo, Rui; Subiaul, Francys; Bradley, Brenda J. (MDPI, 2024-04-25)
    The evolution of facial muscles in dogs has been linked to human preferential selection of dogs whose faces appear to communicate information and emotion. Dogs who convey, especially with their eyes, a sense of perceived helplessness can elicit a caregiving response from humans. However, the facial muscles used to generate such expressions may not be uniquely present in all dogs, but rather specifically cultivated among various taxa and individuals. In a preliminary, qualitative gross anatomical evaluation of 10 canid specimens of various species, we find that the presence of two facial muscles previously implicated in human-directed canine communication, the levator anguli occuli medialis (LAOM) and the retractor anguli occuli lateralis (RAOL), was not unique to domesticated dogs (Canis familiaris). Our results suggest that these aspects of facial musculature do not necessarily reflect selection via human domestication and breeding. In addition to quantitatively evaluating more and other members of the Canidae family, future directions should include analyses of the impact of superficial facial features on canine communication and interspecies communication between dogs and humans.
  • Geohealth Policy Benefits Are Mediated by Interacting Natural, Engineered, and Social Processes
    Calder, Ryan S. D.; Schartup, Amina T. (American Geophysical Union, 2023-08-29)
    Interest in health implications of Earth science research has significantly increased. Articles frequently dispense policy advice, for example, to reduce human contaminant exposures. Recommendations such as fish consumption advisories rarely reflect causal reasoning around tradeoffs or anticipate how scientific information will be received and processed by the media or vulnerable communities. Health is the product of interacting social and physical processes, yet predictable responses are often overlooked. Analysis of physical and social mechanisms, and health and non-health tradeoffs, is needed to achieve policy benefits rather than “policy impact.” Dedicated funding mechanisms would improve the quality and availability of these analyses.
  • Une mauvaise publicité pour l’hydroélectricité québécoise
    Calder, Ryan S. D. (La Presse, 2019-10-11)
  • Canada ignores Muskrat Falls at its peril
    Calder, Ryan S. D. (The Telegram, 2019-10-07)
  • Why Similar Policies Resulted In Different COVID-19 Outcomes: How Responsiveness And Culture Influenced Mortality Rates
    Lim, Tse Yang; Xu, Ran; Ruktanonchai, Nick; Saucedo, Omar; Childs, Lauren M.; Jalali, Mohammad S.; Rahmandad, Hazhir; Ghaffarzadegan, Navid (Health Affairs, 2023-12)
    In the first two years of the COVID-19 pandemic, per capita mortality varied by more than a hundredfold across countries, despite most implementing similar nonpharmaceutical interventions. Factors such as policy stringency, gross domestic product, and age distribution explain only a small fraction of mortality variation. To address this puzzle, we built on a previously validated pandemic model in which perceived risk altered societal responses affecting SARS-CoV-2 transmission. Using data from more than 100 countries, we found that a key factor explaining heterogeneous death rates was not the policy responses themselves but rather variation in responsiveness. Responsiveness measures how sensitive communities are to evolving mortality risks and how readily they adopt nonpharmaceutical interventions in response, to curb transmission.We further found that responsiveness correlated with two cultural constructs across countries: uncertainty avoidance and power distance. Our findings show that more responsive adoption of similar policies saves many lives, with important implications for the design and implementation of responses to future outbreaks.
  • Resident Support for the Federally Mandated Smoke-Free Rule in Public Housing: 2018-2022
    Dearfield, Craig T.; Ulfers, Margaret; Horn, Kimberly; Bernat, Debra H. (MDPI, 2024-01-17)
    This study examines support for the Department of Housing and Urban Development’s (HUD) mandatory smoke-free rule up to four years post-rule among smokers and non-smokers. A repeated cross-sectional design was used where District of Columbia public housing residents aged 18+ (n = 529) completed surveys during three time points: July 2018 (pre-rule), November 2018–March 2020 (post-rule), and September 2020–December 2022 (post-rule + COVID-19). Full support for the rule was indicated by agreeing that smoking should not be allowed in all indoor locations and within 25 feet of buildings. Descriptive statistics showed significant differences in support across time for smokers (5.3%, 30.7%, and 22.5%, respectively) and similar support across time for nonsmokers (48.2%, 52.2%, and 40.0%, respectively). In unstratified regression analysis, pre-rule support was lower than when the rule was in effect (aOR = 0.47, 95% CI = 0.25, 0.90), and tobacco users were less likely to support the rule (aOR = 0.34, 95% CI = 0.23, 0.50). Stratified logistic regression results showed that pre-rule support was lower among smokers compared to post-rule support (aOR = 0.14, 95% CI = 0.03, 0.59); support among nonsmokers did not vary by time. Findings overall indicate low support for the smoke-free rule up to 4 years post-implementation. Engaging residents with the rule and promoting health and well-being may further enhance policy effectiveness and acceptance.
  • Profiles of youth citizenship: A cluster analysis of ethical factors, demographics, and problem-solving disposition
    Bush, Sarah A.; Rudd, Rick D.; Friedel, Curtis R.; Archibald, Thomas G.; Redican, Kerry J. (Mississippi State University Libraries, 2023-12-01)
    Youth have the capacity to drive positive change in their communities through active and engaged citizenship (AEC). Teen-leadership programs provide youth with opportunities to develop the skills necessary to participate as partners in community problem-solving efforts. Situated in relational developmental systems metatheory, this study aimed to examine how cluster membership based upon demographic characteristics, ethical factors, and problem-solving disposition impacted AEC. The findings indicated significant differences between clusters for AEC, civic duty, and civic skills. These differences were predominately observed through membership in long-term or short-term leadership programs, gender, enrollment in honors/AP courses, ethical views, and problem-solving disposition. Youth leadership practitioners should consider avenues for infusing problem-solving and character development in gender inclusive program curriculum to increase likelihood for contributing.
  • COVID-19 related messaging, beliefs, information sources, and mitigation behaviors in Virginia: A cross-sectional survey in the summer of 2020
    Silverman, Rachel; Short, Danielle; Wenzel, Sophie; Friesen, Mary Ann; Cook, Natalie (PeerJ, 2024-01-08)
    Background. Conflicting messages and misleading information related to the coronavirus (COVID-19) pandemic (SARS-CoV-2) have hindered mitigation efforts. It is important that trust in evidence-based public health information be maintained to effectively continue pandemic mitigation strategies. Officials, researchers, and the public can benefit from exploring how people receive information they believe and trust, and how their beliefs influence their behaviors. Methods. To gain insight and inform effective evidence-based public health messaging, we distributed an anonymous online cross-sectional survey from May to July, 2020 to Virginia residents, 18 years of age or older. Participants were surveyed about their perceptions of COVID-19, risk mitigation behaviors, messages and events they felt influenced their beliefs and behaviors, and where they obtained information that they trust. The survey also collected socio-demographic information, including gender, age, race, ethnicity, level of education, income, employment status, occupation, changes in employment due to the pandemic, political affiliation, sexual orientation, and zip code. Analyses included specific focus on the most effective behavioral measures: wearing a face mask and distancing in public. Results. Among 3,488 respondents, systematic differences were observed in information sources that people trust, events that impacted beliefs and behaviors, and how behaviors changed by socio-demographics, political identity, and geography within Virginia. Characteristics significantly associated (p < 0.025) with not wearing a mask in public included identifying as non-Hispanic white, male, Republican political identity, younger age, lower income, not trusting national science and health organizations, believing one or more non-evidence-based messages, and residing in Southwest Virginia in logistic regression. Similar, lesser in magnitude correlations, were observed for distancing in public. Conclusions. This study describes how information sources considered trustworthy vary across different populations and identities, and how these differentially correspond to beliefs and behaviors. This study can assist decision makers and the public to improve and effectively target public health messaging related to the ongoing COVID19 pandemic and future public health challenges in Virginia and similar jurisdictions.
  • Canadian hydropower and the U.S. energy transition: controversies, opportunities, and strategic research directions
    Calder, Ryan S. D.; Borsuk, Mark E.; Mortazavigazar, A.; Howarth, Richard B.; Jackson, Chloe; Mavrommati, Georgia (2023-12-13)
    Recent modeling for the northeast United States suggests that the least-cost decarbonization pathway involves a combination of build-out of domestic renewables generation and increased intertie capacity with Canada. U.S. imports of Canadian hydropower have increased by > 1 TWh per year between 2007–2021 because it is a cost-effective and low-carbon alternative to domestic fossil fuel generation. Yet, increased interconnection capacity and imports are controversial and have been opposed by U.S. environmental groups and members of the public. Development of new hydroelectric reservoirs disrupts foodways and lifeways of Indigenous populations and has greenhouse gas impacts greater than wind and solar (though less than fossil fuel alternatives). Two recently cancelled hydropower transmission projects linking New England and Quebec, Canada demonstrate the need to better understand the gap between pathways that appear optimal from the perspective of energy systems modeling and the pathways that will ultimately be socially and environmentally acceptable. The experience of the northeast mirrors that in other parts of the U.S. where substantial resources have been invested in pursuit of renewable projects that are ultimately abandoned following mobilization of stakeholders with adverse interests or values. A research program integrating environmental and economic modeling seeks to resolve controversies surrounding the use of Canadian hydropower in U.S. energy transitions. This includes conceptual disputes over valuation of hydropower from existing reservoirs in cost-benefit analysis; debates over whether new transmission infrastructure stimulates new generation capacity; and analysis of the relative importance of different benefits and impacts to the public.
  • Alternative approaches for creating a wealth index: the case of Mozambique
    Xie, Kexin; Marathe, Achla; Deng, Xinwei; Ruiz-Castillo, Paula; Imputiua, Saimado; Elobolobo, Eldo; Mutepa, Victor; Sale, Mussa; Nicolas, Patricia; Montana, Julia; Jamisse, Edgar; Munguambe, Humberto; Materrula, Felisbela; Casellas, Aina; Rabinovich, Regina; Saute, Francisco; Chaccour, Carlos J.; Sacoor, Charfudin; Rist, Cassidy (BMJ, 2023-08)
    Introduction: The wealth index is widely used as a proxy for a household's socioeconomic position (SEP) and living standard. This work constructs a wealth index for the Mopeia district in Mozambique using data collected in year 2021 under the BOHEMIA (Broad One Health Endectocide-based Malaria Intervention in Africa) project. Methods: We evaluate the performance of three alternative approaches against the Demographic and Health Survey (DHS) method based wealth index: feature selection principal components analysis (PCA), sparse PCA and robust PCA. The internal coherence between four wealth indices is investigated through statistical testing. Validation and an evaluation of the stability of the wealth index are performed with additional household income data from the BOHEMIA Health Economics Survey and the 2018 Malaria Indicator Survey data in Mozambique. Results: The Spearman's rank correlation between wealth index ventiles from four methods is over 0.98, indicating a high consistency in results across methods. Wealth rankings and households' income show a strong concordance with the area under the curve value of ∼0.7 in the receiver operating characteristic analysis. The agreement between the alternative wealth indices and the DHS wealth index demonstrates the stability in rankings from the alternative methods. Conclusions: This study creates a wealth index for Mopeia, Mozambique, and shows that DHS method based wealth index is an appropriate proxy for the SEP in low-income regions. However, this research recommends feature selection PCA over the DHS method since it uses fewer asset indicators and constructs a high-quality wealth index.
  • The standards of reporting randomized trials in pets (PetSORT): Methods and development processes
    Ruple, Audrey; Sargeant, Jan M.; Selmic, Laura E.; O'Connor, Annette M. (Frontiers, 2023-03)
    BackgroundReporting of clinical trials conducted in client- and shelter-owned dog and cat populations is not optimal, which inhibits the ability to assess the reliability and validity of trial findings and precludes the ability to include some trials in evidence synthesis. ObjectiveTo develop a reporting guideline for parallel group and crossover trials that addresses the unique features and reporting requirements for trials conducted in client- and shelter-owned dog and cat populations. DesignConsensus statement. SettingVirtual. ParticipantsFifty-six experts from North America, the United Kingdom, Europe, and Australia working in academia, government (research and regulatory agencies), industry, and clinical veterinary practice. MethodsA steering committee created a draft checklist for reporting criteria based upon the CONSORT statement and the CONSORT extensions for reporting of abstracts and crossover trials. Each item was presented to the expert participants and was modified and presented again until >85% of participants were in agreement about the inclusion and wording of each item in the checklist. ResultsThe final PetSORT checklist consists of 25 main items with several sub-items. Most items were modifications of items contained in the CONSORT 2010 checklist or the CONSORT extension for crossover trials, but 1 sub-item pertaining to euthanasia was created de novo. ConclusionThe methods and processes used to develop this guideline represent a novel departure from those used to create other reporting guidelines, by using a virtual format. The use of the PetSORT statement should improve reporting of trials conducted in client- and shelter-owned dogs and cats and published in the veterinary research literature.
  • Adverse Health Outcomes Following Hurricane Harvey: A Comparison of Remotely-Sensed and Self-Reported Flood Exposure Estimates
    Ramesh, Balaji; Callender, Rashida; Zaitchik, Benjamin F.; Jagger, Meredith; Swarup, Samarth; Gohlke, Julia M. (American Geophysical Union, 2023-04)
    Remotely sensed inundation may help to rapidly identify areas in need of aid during and following floods. Here we evaluate the utility of daily remotely sensed flood inundation measures and estimate their congruence with self-reported home flooding and health outcomes collected via the Texas Flood Registry (TFR) following Hurricane Harvey. Daily flood inundation for 14 days following the landfall of Hurricane Harvey was acquired from FloodScan. Flood exposure, including number of days flooded and flood depth was assigned to geocoded home addresses of TFR respondents (N = 18,920 from 47 counties). Discordance between remotely-sensed flooding and self-reported home flooding was measured. Modified Poisson regression models were implemented to estimate risk ratios (RRs) for adverse health outcomes following flood exposure, controlling for potential individual level confounders. Respondents whose home was in a flooded area based on remotely-sensed data were more likely to report injury (RR = 1.5, 95% CI: 1.27-1.77), concentration problems (1.36, 95% CI: 1.25-1.49), skin rash (1.31, 95% CI: 1.15-1.48), illness (1.29, 95% CI: 1.17-1.43), headaches (1.09, 95% CI: 1.03-1.16), and runny nose (1.07, 95% CI: 1.03-1.11) compared to respondents whose home was not flooded. Effect sizes were larger when exposure was estimated using respondent-reported home flooding. Near-real time remote sensing-based flood products may help to prioritize areas in need of assistance when on the ground measures are not accessible.
  • Exploring the Relationship between Temporal Fluctuations in Satellite Nightlight Imagery and Human Mobility across Africa
    Rogers, Grant; Koper, Patrycja; Ruktanonchai, Cori; Ruktanonchai, Nick; Utazi, Edson; Woods, Dorothea; Cunningham, Alexander; Tatem, Andrew J.; Steele, Jessica; Lai, Shengjie; Sorichetta, Alessandro (MDPI, 2023-08-30)
    Mobile phone data have been increasingly used over the past decade or more as a pretty reliable indicator of human mobility to measure population movements and the associated changes in terms of population presence and density at multiple spatial and temporal scales. However, given the fact mobile phone data are not available everywhere and are generally difficult to access and share, mostly because of commercial restrictions and privacy concerns, more readily available data with global coverage, such as night-time light (NTL) imagery, have been alternatively used as a proxy for population density changes due to population movements. This study further explores the potential to use NTL brightness as a short-term mobility metric by analysing the relationship between NTL and smartphone-based Google Aggregated Mobility Research Dataset (GAMRD) data across twelve African countries over two periods: 2018–2019 and 2020. The data were stratified by a measure of the degree of urbanisation, whereby the administrative units of each country were assigned to one of eight classes ranging from low-density rural to high-density urban. Results from the correlation analysis, between the NTL Sum of Lights (SoL) radiance values and three different GAMRD-based flow metrics calculated at the administrative unit level, showed significant differences in NTL-GAMRD correlation values across the eight rural/urban classes. The highest correlations were typically found in predominantly rural areas, suggesting that the use of NTL data as a mobility metric may be less reliable in predominantly urban settings. This is likely due to the brightness saturation and higher brightness stability within the latter, showing less of an effect than in rural or peri-urban areas of changes in brightness due to people leaving or arriving. Human mobility in 2020 (during COVID-19-related restrictions) was observed to be significantly different than in 2018–2019, resulting in a reduced NTL-GAMRD correlation strength, especially in urban settings, most probably because of the monthly NTL SoL radiance values remaining relatively similar in 2018–2019 and 2020 and the human mobility, especially in urban settings, significantly decreasing in 2020 with respect to the previous considered period. The use of NTL data on its own to assess monthly mobility and the associated fluctuations in population density was therefore shown to be promising in rural and peri-urban areas but problematic in urban settings.
  • Pharmacokinetics and efficacy of orally administered acetaminophen (paracetamol) in adult horses with experimentally induced endotoxemia
    Mercer, Melissa A.; Davis, Jennifer L.; McKenzie, Harold C.; Messenger, Kristen M.; Schaefer, Emily; Council-Troche, R. McAlister; Werre, Stephen R. (Wiley, 2023-03-01)
    Background: Acetaminophen has been evaluated in horses for treatment of musculoskeletal pain but not as an antipyretic. Objectives: To determine the pharmacokinetics and efficacy of acetaminophen compared to placebo and flunixin meglumine in adult horses with experimentally induced endotoxemia. Animals: Eight university owned research horses with experimentally induced endotoxemia. Methods: Randomized placebo controlled crossover study. Horses were treated with acetaminophen (30 mg/kg PO; APAP), flunixin meglumine (1.1 mg/kg, PO; FLU), and placebo (PO; PLAC) 2 hours after administration of LPS. Plasma APAP was analyzed via LC-MS/MS. Serial CBC, lactate, serum amyloid A, heart rate and rectal temperature were evaluated. Serum IL-1β, IL-6, IL-8, IL-10, and TNF-α were evaluated by an equine-specific multiplex assay. Results: Mean maximum plasma APAP concentration was 13.97 ± 2.74 μg/mL within 0.6 ± 0.3 hour after administration. At 4 and 6 hours after treatment, both APAP (P = <.001, P =.03, respectively) and FLU (P =.0045 and P <.001, respectively) had a significantly greater decrease in rectal temperature compared to placebo. FLU caused greater heart rate reduction than APAP at 4 and 6 hours (P =.004 and P =.04), and PLAC at 4 hours (P =.05) after treatment. Conclusions and Clinical Importance: The pharmacokinetics of acetaminophen in endotoxemic horses differ from those reported by previous studies in healthy horses. Acetaminophen is an option for antipyresis in clinical cases, particularly when administration of traditional NSAIDs is contraindicated.
  • Bead size has a greater effect on in vitro elution from antimicrobial-impregnated calcium sulfate beads than drug concentration
    Olsen, Ronald S.; Sawyere, Dominique M.; Davis, Jennifer L.; Lanz, Otto I.; Werre, Stephen R. (American Veterinary Medical Association, 2023-05)
    OBJECTIVE To compare the elution characteristics of amikacin-impregnated calcium sulfate (CaSO4) beads based on different drug concentrations and bead size configurations. SAMPLE Six groups of amikacin-impregnated CaSO4 beads and one negative control group. PROCEDURES Amikacin-impregnated CaSO4 beads were formed with either 500 mg (low-concentration) or 1 g (high-concentration) of amikacin per 15 g CaSO4 hemihydrate powder. The number of beads necessary to approximate 150 mg of amikacin for each of the 3 bead sizes (3 mm, 5 mm, and 7 mm) at both low and high concentrations were placed in 6 mL of phosphate-buffered saline. The saline was sampled at 14 time points over 28 days. Amikacin concentrations were determined using liquid chromatography-mass spectrometry. RESULTS Smaller beads reached higher mean peak concentrations than larger beads (P < .0006). Peak concentrations for the low-and high-concentration groups were 20.5 mg/mL and 27.4 mg/mL, 13.1 mg/mL and 14.0 mg/mL, and 8.85 mg/mL and 6.75 mg/mL for the 3 mm, 5 mm, and 7 mm beads, respectively. Bead size also affected the length of therapeutic duration, lasting 6 days for the 3 mm and 5 mm beads and 9 days for the 7 mm beads. However, this was only statistically evident among the high-concentration beads (P < .044). Antimicrobial concentration within the same bead sizes did not affect elution. CLINICAL RELEVANCE Amikacin-impregnated CaSO4 beads achieved extreme supratherapeutic eluent concentrations. While additional studies are needed, bead size significantly affected elution with smaller beads reaching higher peak concentrations and 7 mm, high-concentration beads demonstrating a longer therapeutic duration than smaller beads.
  • Microbiological and chemical drinking water contaminants and associated health outcomes in rural Appalachia, USA: A systematic review and meta-analysis
    Darling, Amanda; Patton, Hannah; Rasheduzzaman, Md; Guevara, Rachel; McCray, Joshua; Krometis, Leigh-Anne H.; Cohen, Alasdair (Elsevier, 2023-09)
    In rural areas of the United States, an estimated ~1.8 million people lack reliable access to safe drinking water. Considering the relative dearth of information on water contamination and health outcomes in Appalachia, we conducted a systematic review of studies of microbiological and chemical drinking water contamination and associated health outcomes in rural Appalachia. We pre-registered our protocols, limiting eligibility to primary data studies published from 2000 to 2019, and searched four databases (PubMed, EMBASE, Web of Science, and the Cochrane Library). We used qualitative syntheses, meta-analyses, risk of bias analysis, and meta-regression to assess reported findings, with reference to US EPA drinking water standards. Of the 3452 records identified for screening, 85 met our eligibility criteria. 93 % of eligible studies (n = 79) used cross-sectional designs. Most studies were conducted in Northern (32 %, n = 27) and North Central (24 %, n = 20) Appalachia, and only 6 % (n = 5) were conducted exclusively in Central Appalachia. Across studies, E. coli were detected in 10.6 % of samples (sample-size-weighted mean percentage from 4671 samples, 14 publications). Among chemical contaminants, sample-size-weighted mean concentrations for arsenic were 0.010 mg/L (n = 21,262 samples, 6 publications), and 0.009 mg/L for lead (n = 23,259, 5 publications). 32 % (n = 27) of studies assessed health outcomes, but only 4.7 % (n = 4) used case-control or cohort designs (all others were cross-sectional). The most commonly reported outcomes were detection of PFAS in blood serum (n = 13), gastrointestinal illness (n = 5), and cardiovascular-related outcomes (n = 4). Of the 27 studies that assessed health outcomes, 62.9 % (n = 17) appeared to be associated with water contamination events that had received national media attention. Overall, based on the number and quality of eligible studies identified, we could not reach clear conclusions about the state of water quality, or its impacts on health, in any of Appalachia's subregions. More epidemiologic research is needed to understand contaminated water sources, exposures, and potentially associated health outcomes in Appalachia.
  • Approaches Used to Construct Antibiograms for Dogs in a Veterinary Teaching Hospital in the United States
    Ekakoro, John E.; Guptill, Lynn; Hendrix, Kenitra; Anderson, Melinda; Ruple, Audrey (MDPI, 2023-06-09)
    Non-judicious antimicrobial use (AMU) is a major driver of antimicrobial resistance (AMR). In human hospitals, cumulative antibiograms are often used by clinicians to evaluate local susceptibility rates and to select the most appropriate empiric therapy with the aim of minimizing inappropriate AMU. However, the use of cumulative antibiograms to guide empiric antimicrobial therapy in veterinary hospitals in the United States is limited, and there are no specific guidelines or standardized methods available for the construction of antibiograms in veterinary clinical settings. The objective of this methods article is to describe the approaches that were used to construct antibiograms from clinical samples collected from dogs seen at a veterinary teaching hospital. Laboratory data for 563 dogs for the period from 1 January 2015 to 31 December 2015 was utilized. We used the Clinical and Laboratory Standards Institute (CLSI) guidelines for use in the construction of the antibiograms in human healthcare settings as the basis for the veterinary antibiograms. One general antibiogram and antibiograms stratified by hospital section, the anatomic region of sample collection/by sample type, were created and the challenges encountered in preparing these antibiograms were highlighted. The approaches described could be useful in guiding veterinary antibiogram development for empiric therapy.
  • Future Impacts of Hydroelectric Power Development on Methylmercury Exposures of Canadian Indigenous Communities
    Calder, Ryan S. D.; Schartup, Amina T.; Li, Miling; Valberg, Amelia P.; Balcom, Prentiss H.; Sunderland, Elsie M. (American Chemical Society, 2016-12-06)
    Developing Canadian hydroelectric resources is a key component of North American plans for meeting future energy demands. Microbial production of the bioaccumulative neurotoxin methylmercury (MeHg) is stimulated in newly flooded soils by degradation of labile organic carbon and associated changes in geochemical conditions. We find all 22 Canadian hydroelectric facilities being considered for near-term development are located within 100 km of indigenous communities. For a facility in Labrador, Canada (Muskrat Falls) with planned completion in 2017, we probabilistically modeled peak MeHg enrichment relative to measured baseline conditions in the river to be impounded, downstream estuary, locally harvested fish, birds and seals, and three Inuit communities. Results show a projected 10-fold increase in riverine MeHg levels and a 2.6-fold increase in estuarine surface waters. MeHg concentrations in locally caught species increase 1.3 to 10-fold depending on time spent foraging in different environments. Mean Inuit MeHg exposure is forecasted to double following flooding and over half of the women of childbearing age and young children in the most northern community are projected to exceed the U.S. EPA's reference dose. Equal or greater aqueous MeHg concentrations relative to Muskrat Falls are forecasted for 11 sites across Canada, suggesting the need for mitigation measures prior to flooding.
  • Antimicrobial susceptibility and risk factors for resistance among Escherichia coli isolated from canine specimens submitted to a diagnostic laboratory in Indiana, 2010-2019
    Ekakoro, John E.; Hendrix, G. Kenitra; Guptill, Lynn F.; Ruple, Audrey (Public Library of Science, 2022-08)
    Escherichia coli (E. coli) is the most common Gram-negative pathogen isolated in human infections. Antimicrobial resistant (AMR) E. coli originating from dogs may directly or indirectly cause disease in humans. The objective of this study was to calculate the proportion of antimicrobial susceptible E. coli isolated from canine specimens submitted to the Indiana Animal Disease Diagnostic Laboratory and to identify temporal patterns of susceptibility among these isolates. Susceptibility data of 2,738 E. coli isolates from dogs from 2010 through 2019 were used in this study. Proportions of isolates susceptible to the various antimicrobials were calculated using SAS statistical software and the Cochran-Armitage trend test was used to investigate the temporal trends in susceptibility. A multivariable binary logistic regression model was built to investigate the association between host factors and AMR. Overall, 553/2,738 (20.2%) of the isolates were susceptible to 17 of the 27 antimicrobials examined. Of the 2,638 isolates examined for amikacin susceptibility, 2,706 (97.5%) were susceptible, 2,657/2,673 (99.4%) isolates were susceptible to imipenem, and 2,099/2,670 (78.6%) were susceptible to marbofloxacin. A significant decreasing trend in susceptibility was observed for amoxicillin-clavulanic acid (P<0.0001), ampicillin (P<0.0001), Cefazolin (P<0.0001), ceftazidime (P = 0.0067), chloramphenicol (P<0.0001), and orbifloxacin (P = 0.008). The overall percentage of AMR isolates (isolates not susceptible to at least one antimicrobial) was 61.7% (1,690/2,738) and 29.3% (801/2,738) of isolates were multidrug resistant. Multivariable regression analyses showed significant associations between AMR and age (P = 0.0091), breed (P = 0.0008), and sample isolation site/source (P<0.0001). The decreasing trend in the proportion of isolates susceptible to several beta-lactam antimicrobials suggests that resistance of Escherichia coli in dogs to these antimicrobials could be increasing in Indiana. The decreasing trend in susceptibility to these drugs could be due to selection pressure from antimicrobial use.