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Purpose: Extraintestinal pathogenic E. coli (ExPEC) are important pathogens causing community-acquired infections in humans, including bloodstream infections (BSIs), and may also colonize and infect animals. Our aim was to investigate associations between incidence rates (IRs) of BSIs caused by ExPEC and number of dogs and cats in communities in Calgary. Methods: We used a well-characterized collection of blood isolates (n = 685) from Calgary, Alberta, Canada (2016). We used a combination of a seven-single-nucleotide-polymorphism quantitative PCR to type ExPEC into sequence types (STs). Calgary census data were used to estimate IRs per city community, as well as to investigate associations between number of companion animals per community, as obtained from licensing data, and IR of BSIs caused by each dominant ST. Results: From the 685 isolates available, ExPEC ST131 was most prevalent (21.3% of included isolates), followed by ST73 (13.7%), ST69 (8.2%), ST95 (6.7%), and ST1193 (5.3%), respectively. Incidence of BSIs caused by ExPECs among Calgary residents was 48.8 cases per 100,000 resident-years, whereas communities had on average of 1.7 companion animals per 10 residents. No association between the number of dogs and IR of BSIs caused by ExPECs was detected for any ST. Conversely, the incidence rate of BSIs caused by ST73 was 3.6 times higher (95%CI 1.3–9.99) for every increase of 1 cat per 10 habitants in communities. Conclusions: Number of cats per habitant was positively associated with the incidence of BSIs caused by ExPEC ST73. [ABSTRACT FROM AUTHOR]

Global expansion of antimicrobial drug-resistant Escherichia coli sequence type (ST) 131 is unrivaled among human bacteria. Understanding trends among ST131 clades will help with designing prevention strategies. We screened E. coli from blood samples (n = 1,784) obtained in Calgary, Alberta, Canada, during 2006, 2012, and 2016 by PCR for ST131 and positive samples (n = 344) underwent whole-genome sequencing. The incidence rate per 100,000 residents increased from 4.91 during 2006 to 12.35 during 2012 and 10.12 during 2016. ST131 belonged to clades A (10%), B (9%), and C (81%). Clades C1-nonM27 and B were common during 2006, and C2 containing blaCTX-M-15, C1-M27 containing blaCTX-M-27, and A were responsible for the increase of ST131 during 2012 and 2016. C2 was the most antimicrobial drug-resistant subclade and increased exponentially over time. Eradicating ST131, more specifically the C2 subclade, will lead to considerable public health benefits for persons in Calgary. [ABSTRACT FROM AUTHOR]

Background: Anaerobes are a relatively uncommon but important cause of bloodstream infection. However, their epidemiology has not been well defined in non-selected populations. We sought to describe the incidence of, risk factors for, and outcomes associated with anaerobic bacteremia. Methods: Population-based surveillance for bacteremia with anaerobic microorganisms was conducted in the Calgary area (population 1.2 million) during the period from 2000 to 2008. Results: A total of 904 incident cases were identified, for an overall population incidence of 8.7 per 100,000 per year; 231 (26 %) were nosocomial, 300 (33 %) were healthcare-associated community-onset, and 373 (41 %) were community-acquired. Elderly males were at the greatest risk. The most common pathogens identified were: Bacteroides fragilis group (3.6 per 100,000), Clostridium (non- perfringens) spp. (1.1 per 100,000), Peptostreptococcus spp. (0.9 per 100,000), and Clostridium perfringens (0.7 per 100,000). Non-susceptibility to metronidazole was 2 %, to clindamycin 17 %, and to penicillin 42 %. Relative to the general population, risk factors for anaerobic bloodstream infection included: male sex, increasing age, a prior diagnosis of cancer, chronic liver disease, heart disease, diabetes mellitus, stroke, inflammatory bowel disease, human immunodeficiency virus (HIV) infection, chronic obstructive pulmonary disease (COPD), and/or hemodialysis-dependent chronic renal failure (HDCRF). The 30-day mortality was 20 %. Increasing age, nosocomial acquisition, presence of malignancy, and several other co-morbid illnesses were independently associated with an increased risk of death. Conclusion: Anaerobic bloodstream infection is responsible for a significant burden of disease in general populations. The data herein establish the extent to which anaerobes contribute to morbidity and subsequent mortality. This information is key in developing preventative, empiric treatment and research priorities. [ABSTRACT FROM AUTHOR]

In the Calgary Health Region during 2000-2003, prospective, active, population-based laboratory surveillance for all cefoxitin-resistant Escherichia coli isolates was performed. Isolates were screened with an inhibitor-based disk test, and plasmid-mediated types were identified by multiplex PCR with sequencing. A total of 369 AmpC β-lactamase--producing E. coli isolates were identified; annual incidence rates were 1.7, 4.3, 11.2, and 15 per 100,000 residents for each year, respectively. AmpC β-lactamase-producing E. coli was 5x more likely to be isolated from female than male patients across all age groups except <1 year. Of these isolates, 83% were community onset, and urine was the principal site of isolation (90% of patients). PCR showed that 125 (34%) were positive for blacmy genes; sequencing identified these enzymes to be CMY-2. In this large Canadian region, AmpC β-lactamase--producing E. coli is an emerging community pathogen that commonly causes urinary tract infections in older women. [ABSTRACT FROM AUTHOR]

Global expansion of antimicrobial drug-resistant Escherichia coli sequence type (ST) 131 is unrivaled among human bacteria. Understanding trends among ST131 clades will help with designing prevention strategies. We screened E. coli from blood samples (n = 1,784) obtained in Calgary, Alberta, Canada, during 2006, 2012, and 2016 by PCR for ST131 and positive samples (n = 344) underwent whole-genome sequencing. The incidence rate per 100,000 residents increased from 4.91 during 2006 to 12.35 during 2012 and 10.12 during 2016. ST131 belonged to clades A (10%), B (9%), and C (81%). Clades C1-nonM27 and B were common during 2006, and C2 containing blaCTX-M-15, C1-M27 containing blaCTX-M-27, and A were responsible for the increase of ST131 during 2012 and 2016. C2 was the most antimicrobial drug-resistant subclade and increased exponentially over time. Eradicating ST131, more specifically the C2 subclade, will lead to considerable public health benefits for persons in Calgary. [ABSTRACT FROM AUTHOR]

Abstract: Background: Although Klebsiella pneumoniae is the second most common cause of Gram-negative bloodstream infections, its epidemiology has not been defined in a nonselected population. We sought to describe the incidence of, risk factors for, and outcomes associated with K. pneumoniae bacteremia. Methods: Population-based surveillance for K. pneumoniae bacteremia was conducted in the Calgary Health Region (population 1.2 million) from 2000 to 2007. Results: A total of 640 episodes of K. pneumoniae bacteremia were identified for an overall annual population incidence of 7.1 per 100,000; 174 (27%) were nosocomial, 276 (43%) were healthcare-associated community onset, and 190 (30%) were community acquired. Elderly patients and men were at highest risk for K. pneumoniae bacteremia. Dialysis, solid-organ transplantation, chronic liver disease, and cancer were the most important risk factors for acquiring K. pneumoniae bacteremia. Rates of resistance to trimethoprim/sulfamethoxazole increased significantly during 2000 to 2007. The case fatality rate was 20%, and the annual population mortality rate was 1.3 per 100,000. Increasing age, nosocomial acquisition, non-urinary and non-biliary focus of infection, and several comorbid illnesses were independently associated with an increased risk of death. Conclusion: This is the first population-based study to document the major burden of illness associated with K. pneumoniae bacteremia and identifies groups at increased risk of acquiring and dying of these infections. [Copyright &y& Elsevier]