Sylvia L Checkley

Sylvia L Checkley
The University of Calgary | HBI · Department of Ecosystem and Public Health

DVM, PhD

About

126
Publications
27,017
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,603
Citations
Citations since 2016
59 Research Items
1255 Citations
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
2016201720182019202020212022050100150200250
Additional affiliations
September 2009 - present
The University of Calgary
Position
  • Professor (Associate)
April 2004 - August 2009
Government of Alberta, Agriculture and Rural Development
Position
  • Veterinary Epidemiologist

Publications

Publications (126)
Article
Full-text available
Glucocorticoid (GC) levels are increasingly and widely used as biomarkers of hypothalamic–pituitary–adrenal (HPA) axis activity to study the effects of environmental changes and other perturbations on wildlife individuals and populations. However, identifying the intrinsic and extrinsic factors that influence GC levels is a key step in endocrinolog...
Chapter
This chapter discusses wildlife health surveillance in arctic communities first focusing on general principles: What is surveillance? Why it is important? What are some of the different approaches that can be used? Then, some previous or current surveillance programs are discussed. An example of muskox health surveillance in Nunavut, Canada, demons...
Article
Full-text available
Erysipelothrix rhusiopathiae was detected immunohistochemically in contagious ecthyma (orf virus) dermatitis in two muskoxen (Ovibos moschatus), harvested and found dead in 2014 and 2015, respectively, on Victoria Island, Canada. This may help target further research on E. rhusiopathiae epidemiology and mechanisms of infection in muskoxen, recently...
Article
Full-text available
Current limitations in the understanding and control of antimicrobial resistance (AMR) in Canada are described through a comprehensive review focusing on: (1) treatment optimization; (2) surveillance of antimicrobial use and AMR; and (3) prevention of transmission of AMR. Without addressing gaps in identified areas, sustained progress in AMR mitiga...
Article
The prevalence and levels of enteric viruses in untreated groundwater of private wells used for drinking and/or agricultural practices in rural Alberta were studied using the qPCR panel assay, integrated cell culture with qPCR and cell culture in the volume of 500 liters per sample through serial sampling. Seven viruses were assessed including aden...
Article
Full-text available
Enterococcus spp. have arisen as important nosocomial pathogens and are ubiquitous in the gastrointestinal tracts of animals and the environment. They carry many intrinsic and acquired antimicrobial resistance genes. Because of this, surveillance of Enterococcus spp. has become important with whole genome sequencing emerging as the preferred method...
Article
Full-text available
Muskoxen (Ovibos moschatus), a taxonomically unique Arctic species, are increasingly exposed to climate and other anthropogenic changes. It is critical to develop and validate reliable tools to monitor their physiological stress response in order to assess the impacts of these changes. Here, we measured fecal glucocorticoid metabolite (FGM) levels...
Article
Salmonella infections are a major human health concern. In the elderly and immunocompromised, infections can be life‐threatening and may require antibiotic therapy. Where antibiotic therapy is required, antimicrobials of choice include fluoroquinolones and extended‐spectrum cephalosporins (ESC). The aim of this study is to utilize data from the Can...
Article
Full-text available
Infectious laryngotracheitis (ILT) is an infectious upper respiratory tract disease that impacts the poultry industry worldwide. ILT is caused by an alphaherpesvirus commonly referred to as infectious laryngotracheitis virus (ILTV). Vaccination with live attenuated vaccines is practiced regularly for the control of ILT. However, extensive and impro...
Article
Full-text available
Horizontal gene transfer is an important mechanism which facilitates bacterial populations in overcoming antimicrobial treatment. In this study, a total of 120 Escherichia coli and 62 Salmonella enterica subsp. enterica isolates were isolated from broiler chicken farms in Alberta. Fourteen serovars were identified among Salmonella isolates. Thirty...
Article
Full-text available
Livestock farming plays an important role in supporting the livelihood of resource-poor subsistence farmers in Bhutan. However, ticks and tick-borne diseases (TBDs) are one of the major constraints to livestock farming due to their negative effect on health and production. To date, no study has been conducted in Bhutan to assess farmers’ knowledge,...
Article
Full-text available
Tick infestation is the most reported parasitological problem in cattle in Bhutan. In May and June 2019, we collected ticks from 240 cattle in two districts of Eastern Bhutan. Tick presence, diversity, and infestation prevalence were examined by morphological identification of 3600 live adult ticks. The relationships between cattle, geographic fact...
Article
Muskoxen (Ovibos moschatus) are increasingly exposed to a broad diversity of stressors in their rapidly changing Arctic environment. There is an urgent need to develop validated tools to monitor the impact of these stressors on the hypothalamic–pituitary–adrenal (HPA) axis activity of muskoxen to help inform conservation actions. Here, we evaluated...
Article
Full-text available
Echinococcus multilocularis, the aetiological agent of human Alveolar Echinococcosis (AE), is transmitted between small mammals and wild or domestic canids. Dogs infected with E. multilocularis can transmit this infection to humans and can themselves be infected with canine AE as dead-end hosts. Whereas E. multilocularis infections in wild hosts an...
Article
Campylobacter infections in humans are usually self-limiting; however, antibiotic intervention may be necessary in the case of severe infection. Fluoroquinolones are often the drug of choice for treatment of campylobacteriosis; however, resistance to these drugs can develop rapidly, complicating treatment protocols. Increasing resistance to fluoroq...
Article
Full-text available
Infectious laryngotracheitis virus (ILTV) is a herpes virus that causes an acute respiratory disease of poultry known as infectious laryngotracheitis (ILT). Chicken embryo origin (CEO) and tissue culture origin (TCO) live attenuated vaccines are routinely used for the control of ILT. However, vaccine virus is known to revert to virulence, and it ha...
Preprint
Full-text available
Horizontal gene transfer is an important mechanism which facilitates bacterial populations in overcoming antimicrobial treatment. In this study, a total of 120 Escherichia coli and 62 Salmonella enterica subsp. enterica isolates were isolated from poultry farms in Alberta. Fourteen serovars were identified among Salmonella isolates. Thirty one perc...
Article
Full-text available
A growing body of evidence has demonstrated that extraintestinal pathogenic E. coli (ExPEC), such as the urinary pathogenic E. coli (UPEC), are common constituents of treated wastewater, and therefore represent a potential public health risk. However, no single virulence gene, or set of virulence genes, can be used to conclusively identify this gen...
Article
Full-text available
Approximately 238,000 to 450,000 Albertans rely on private water wells for their water needs. In Canada, private well owners are responsible for monitoring and maintaining the quality of their water well, yet studies in Alberta indicate that owners do not undertake regular well maintenance or testing. This survey obtained information regarding farm...
Article
Full-text available
Background Muskoxen are a key species of Arctic ecosystems and are important for food security and socio-economic well-being of many Indigenous communities in the Arctic and Subarctic. Between 2009 and 2014, the bacterium Erysipelothrix rhusiopathiae was isolated for the first time in this species in association with multiple mortality events in Ca...
Article
Full-text available
Health problems can arise from consuming contaminated well water. Well water testing can help prevent negative health outcomes associated with consuming contaminated water. The aim of this study was to understand the factors influencing well owner decisions to conduct water testing through the theoretical lens of the Health Belief Model. We conduct...
Article
Full-text available
Shiga toxin-producing E. coli (STEC) represent a major concern for waterborne disease outbreaks associated with consumption of contaminated groundwater. Over 4 million people rely on private groundwater systems as their primary drinking water sources in Canada, and for which many of these systems do not meet current standards for water quality. Thi...
Article
Full-text available
Brucella serostatus was evaluated in 3189 muskoxen sampled between 1989 and 2016 from various locations of the Canadian Arctic archipelago and mainland, near the communities of Sachs Harbour and Ulukhaktok, Northwest Territories, and Cambridge Bay and Kugluktuk, Nunavut. Brucella antibodies were found only in muskoxen sampled around Cambridge Bay,...
Article
Full-text available
Background We have previously reported, in a systematic review of 181 studies, that restriction of antibiotic use in food-producing animals is associated with a reduction in antibiotic-resistant bacterial isolates. While informative, that report did not concretely specify whether different types of restriction are associated with differential effec...
Article
Aquifer vulnerability index methods are commonly used for assessing groundwater vulnerability to surface contaminants. However, the methods have primarily been developed for dissolved contaminants. Microbial contaminants have unique characteristics that result in different transport behavior in the subsurface, and thus require different tools. Key...
Article
Full-text available
Muskoxen (Ovibos moschatus) are an integral component of Arctic biodiversity. Given low genetic diversity, their ability to respond to future and rapid Arctic change is unknown, although paleontological history demonstrates adaptability within limits. We discuss status and limitations of current monitoring, and summarize circumpolar status and rece...
Article
Full-text available
Dog bites are a public health concern that also implicates animal welfare, with negative outcomes such as rehoming or euthanasia for the animals responsible. Previous research has shown that the severity of dog-bite injuries reflects multiple factors, including the degree of inhibition exhibited by dogs and how people behave towards dogs. This stud...
Article
Full-text available
Water wells are important in providing water for rural populations that are far removed from municipal water supplies. Over 400,000 rural Albertans use water wells for domestic purposes. The responsibility of well water management lies with well owners. Perceptions of well water quality become important in influencing the adoption of well water man...
Article
Full-text available
Antimicrobial resistance is considered one of the greatest threats to global and public health today. The World Health Organization, the Food and Agriculture Organization, and the World Organisation for Animal Health, known as the Tripartite Collaboration, have called for urgent action. We have previously published a systematic review of 181 studie...
Article
Full-text available
We previously demonstrated the existence of naturalized strains of E. coli in wastewater and herein perform an in-depth comparative whole genome analysis of these strains (n=17). Fourteen of the Canadian E. coli strains, isolated from geographically separated wastewater treatment plants, were virtually identical at the core genome and were ³96% sim...
Article
Full-text available
Waterborne outbreaks of infectious disease continue to be a public health risk, particularly those in areas where testing of private and public small system groundwater systems is left to the owners/overseers of these wells who may not recognize the importance of testing and treatment. Recognizing factors associated with contamination of wells is i...
Article
Full-text available
The objectives of this study were to describe the antimicrobial susceptibility and serotypes of clinical Salmonella spp. isolates from Alberta cattle, to inform antimicrobial stewardship decisions for Alberta bovine veterinarians and to provide data for national surveillance. Isolates were collected from cattle and serotyped by Alberta Agriculture...
Article
Risk assessments are utilized to understand the risks associated with bacterial foodborne pathogens with increased antimicrobial resistance (AMR). This review aimed at identifying and describing the literature on risk assessments for the study of antimicrobial resistance of foodborne bacteria in humans, with focus only on products intended for the...
Article
Selective pressure exerted by the widespread use of antibacterial drugs is accelerating the development of resistant bacterial populations. The purpose of this scoping review was to summarise the range of studies that use dynamic models to analyse the problem of bacterial resistance in relation to antibacterial use in human and animal populations....
Article
Full-text available
Understanding human-wildlife relationships and interactions is crucial to implementing policies and practices related to wildlife and public health that are locally relevant and adapted to local communities and needs. With the goal of informing a community-based participatory muskox health surveillance system in the community of Iqaluktutiaq (Cambr...
Article
Emergence and dissemination of antimicrobial resistance (AMR) in food-borne bacteria is a public health issue. Retail meat is considered an important carrier for antimicrobial-resistant Escherichia coli. Currently, resistance of E. coli strains to third generation cephalosporins are of particular concern, with significant potential animal and publi...
Article
As shrimp farming can be an important means of income generation, particularly among Sri Lanka’s rural communities, it is important that this industry grows in a sustainable manner, starting at the farm level. The objectives of this study were to; 1) create baseline farm-level sustainability indices for smallholder shrimp farms in Sri Lanka using b...
Article
Monitoring and surveillance of wildlife populations, including demographics and health, is often challenging, particularly in resource-constrained and remote settings. However, in areas characterized by subsistence oriented societies, the users of renewable resources hold a vast and holistic ecological knowledge about the natural environment. This...
Article
The extra-label use of ceftiofur in Canadian hatcheries was cause for concern due to an increased prevalence of ceftiofur resistant Salmonella Heidelberg in chickens and humans in Québec. Due to ongoing concerns related to human health the use of ceftiofur was eventually phased out of the poultry production industry in 2014-2015. Simultaneous resis...
Article
With increasing stress on our water resources and recent waterborne disease outbreaks, understanding the epidemiology of waterborne pathogens is crucial to build surveillance systems. The purpose of this study was to explore techniques for describing microbial water quality in rural drinking water wells, based on spatiotemporal analysis, time serie...
Presentation
Antimicrobial resistance is a threat to global public health. Although no longer used, use of ceftiofur in Canadian hatcheries has been associated with an increased prevalence of Salmonella Heidelberg in humans and poultry. The A2C pattern of resistance occurs when an isolate displays simultaneous resistance to amoxicillin-clavulanic acid, cefoxiti...
Poster
Water is essential for life. In rural Alberta, approximately 600,000 people rely on private groundwater or stored water for drinking purposes. Up to 25% of such water systems fail current drinking water quality parameters. Waterborne pathogens can be transmitted by consumption of untreated/improperly treated groundwater. This study aims to better u...
Research
Full-text available
options.irpp.org/magazines/may-2017/the-global-challenge-of-antimicrobial-resistance/
Article
A devastating flood occurred in southern Alberta on June 19, 2013, from greater than normal snowfalls in the Rocky Mountains and excess precipitation during the early spring that left soils saturated and unable to absorb any additional precipitation. This flood was Canada's most costly natural disaster, with five to six billion Canadian dollars in...
Data
Detection of Erysipelothrix tonsillarum in ungulate samples.
Data
Presence of genes associated with Erysipelothrix rhusiopathiae pathogenicity among the isolates included in this study.
Data
Methods: samples tested for Erysipelothrix rhusiopathiae from non-ungulate species.
Data
Primers used for Sanger sequencing confirmation of unique single nucleotide polymorphisms found in different isolates from Banks Island muskox 172.
Data
Results of samples from non-ungulate species tested for Erysipelothrix rhusiopathiae.
Article
Full-text available
Northern ecosystems are currently experiencing unprecedented ecological change, largely driven by a rapidly changing climate. Pathogen range expansion, and emergence and altered patterns of infectious disease, are increasingly reported in wildlife at high latitudes. Understanding the causes and consequences of shifting pathogen diversity and host-p...
Article
Spatial and seasonal patterns in the positive rates of total coliforms and Escherichia coli in Alberta well water were investigated to gain insight into well water microbial contamination. Analysis was conducted in the presence of total coliforms (77 135 tests) and E. coli (77 132 tests) in well water from 2004 to 2009 along with monthly estimates...
Article
Full-text available
An adult male muskox ( Ovibos moschatus ), harvested on 26 August 2014 on Victoria Island, Nunavut, in the Canadian Arctic, had proliferative dermatitis on the muzzle and fetlocks suggestive of contagious ecthyma or orf (Parapoxvirus). Histopathologic features of the lesions were consistent with this diagnosis. Orf virus DNA, phylogenetically simil...
Article
Full-text available
Importance: The results of this study demonstrate the importance of assay validation upon data interpretation of environmental monitoring for Campylobacter when using molecular-based assays. Previous studies describing Campylobacter prevalence in Canada utilized primers that we have determined to be non-specific due to their cross-amplification of...
Article
Injuries due to interactions with dogs (e.g. bites, collisions, etc) are an important public health concern from both a health and an economic perspective. The consequences of these injuries can be both physical (injury, pain, infection, disfiguration) and psychological. The purpose of this study is to understand the prevalence and characteristics...
Article
Objectives: Clostridium difficile (C. difficile) may worsen the prognosis of ulcerative colitis (UC). The objectives of this study were to: (i) validate the International Classification of Diseases-10 (ICD-10) code for C. difficile; (ii) determine the risk of C. difficile infection after diagnosis of UC; (iii) evaluate the effect of C. difficile i...
Poster
This study used data from the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) broiler surveillance program to examine the risk factors for an A2C resistant E.coli isolate (A2C-REI) among broiler flocks in Canada.
Article
The objectives of this study were to estimate the prevalence of antimicrobial resistance (AMR) and to investigate the associations between exposures to antimicrobial drugs (AMDs) and AMR in fecal non-type specific Escherichia coli (NTSEC) recovered from a large population of feedlot cattle. Two-stage random sampling was used to select individually...
Data
Antimicrobial drugs used in the study population and the ADD assigned to a single treatment. (DOCX)