To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
The coronavirus disease 2019 (COVID-19) pandemic has placed significant burden on healthcare systems. We compared Clostridioides difficile infection (CDI) epidemiology before and during the pandemic across 71 hospitals participating in the Canadian Nosocomial Infection Surveillance Program. Using an interrupted time series analysis, we showed that CDI rates significantly increased during the COVID-19 pandemic.
The Canadian Nosocomial Infection Surveillance Program conducted point-prevalence surveys in acute-care hospitals in 2002, 2009, and 2017 to identify trends in antimicrobial use.
Eligible inpatients were identified from a 24-hour period in February of each survey year. Patients were eligible (1) if they were admitted for ≥48 hours or (2) if they had been admitted to the hospital within a month. Chart reviews were conducted. We calculated the prevalence of antimicrobial use as follows: patients receiving ≥1 antimicrobial during survey period per number of patients surveyed × 100%.
In each survey, 28−47 hospitals participated. In 2002, 2,460 (36.5%; 95% CI, 35.3%−37.6%) of 6,747 surveyed patients received ≥1 antimicrobial. In 2009, 3,566 (40.1%, 95% CI, 39.0%−41.1%) of 8,902 patients received ≥1 antimicrobial. In 2017, 3,936 (39.6%, 95% CI, 38.7%−40.6%) of 9,929 patients received ≥1 antimicrobial. Among patients who received ≥1 antimicrobial, penicillin use increased 36.8% between 2002 and 2017, and third-generation cephalosporin use increased from 13.9% to 18.1% (P < .0001). Between 2002 and 2017, fluoroquinolone use decreased from 25.7% to 16.3% (P < .0001) and clindamycin use decreased from 25.7% to 16.3% (P < .0001) among patients who received ≥1 antimicrobial. Aminoglycoside use decreased from 8.8% to 2.4% (P < .0001) and metronidazole use decreased from 18.1% to 9.4% (P < .0001). Carbapenem use increased from 3.9% in 2002 to 6.1% in 2009 (P < .0001) and increased by 4.8% between 2009 and 2017 (P = .60).
The prevalence of antimicrobial use increased between 2002 and 2009 and then stabilized between 2009 and 2017. These data provide important information for antimicrobial stewardship programs.
Background: Healthcare services are increasingly shifting from inpatient to outpatient settings. Outpatient settings such as emergency departments (EDs), oncology clinics, dialysis clinics, and day surgery often involve invasive procedures with the risk of acquiring healthcare-associated infections (HAIs). As a leading cause of HAI, Clostridioides difficile infection (CDI) in outpatient settings has not been sufficiently described in Canada. The Canadian Nosocomial Infection Surveillance Program (CNISP) aims to describe the epidemiology, molecular characterization, and antimicrobial susceptibility of outpatient CDI across Canada. Methods: Epidemiologic data were collected from patients diagnosed with CDI from a network of 47 adult and pediatric CNISP hospitals. Patients presenting to an outpatient setting such as the ED or outpatient clinics were considered as outpatient CDI. Cases were considered HAIs if the patient had had a healthcare intervention within the previous 4 weeks, and they were considered community-associated if there was no history of hospitalization within the previous 12 weeks. Clostridioides difficile isolates were submitted to the National Microbiology Laboratory for testing during an annual 2-month targeted surveillance period. National and regional rates of CDI were stratified by outpatient location. Results: Between January 1, 2015, and June 30, 2019, 2,691 cases of outpatient-CDI were reported, and 348 isolates were available for testing. Most cases (1,475 of 2,691, 54.8%) were identified in outpatient clinics, and 72.8% (1,960 of 2,691) were classified as community associated. CDI cases per 100,000 ED visits were highest in 2015, at 10.3, and decreased to 8.1 in 2018. Rates from outpatient clinics decreased from 3.5 in 2016 to 2.7 in 2018 (Fig. 1). Regionally, CDI rates in the ED declined in Central Canada and increased in the West after 2016. Rates in outpatient clinics were >2 times higher in the West compared to other regions. RT027 associated with NAP1 was most common among ED patients (26 of 195, 13.3%), whereas RT106 associated with NAP11 was predominant in outpatient clinics (22 of 189, 11.6%). Overall, 10.4% of isolates were resistant to moxifloxacin, 0.5% were resistant to rifampin, and 24.2% were resistant to clindamycin. No resistance was observed for metronidazole, vancomycin, or tigecycline. Compared to CNISP inpatient CDI data, outpatients with CDI were younger (51.8 ± 23.3 vs 64.2 ± 21.6; P < .001), included more females (56.4% vs 50.9%; P < .001), and were more often treated with metronidazole (63.0% vs 56.1%; P < .001). Conclusions: For the first time, CDI cases identified in outpatient settings were characterized in a Canadian context. Outpatient CDI rates are decreasing overall, but they vary by region. Predominant ribotypes vary based on outpatient location. Outpatients with CDI are younger and are more likely female than inpatients with CDI.
Disclosures: Susy Hota reports contract research for Finch Therapeutics.
Background: Carbapenemase-producing Enterobacterales (CPE) have rapidly become a global health concern and are associated with substantial morbidity and mortality due to limited treatment options. Travel to endemic areas, especially healthcare exposure in these areas, is an important risk factor for acquisition. We describe the evolving epidemiology, molecular features, and outcomes of CPE in Canada through surveillance by the Canadian Nosocomial Infection Surveillance Program (CNISP). Methods: CNISP has conducted surveillance for CPE among inpatients and outpatients of all ages since 2010. Participating acute-care facilities submit eligible specimens to the National Microbiology Laboratory for detection of carbapenemase production, and epidemiological data are collected. Incidence rates per 10,000 patient days are calculated based on inpatient data. Results: In total, 59 CNISP hospitals in 10 Canadian provinces representing 21,789 beds and 6,785,013 patient days participated in this surveillance. From 2010 to 2018, 118 (26%) CPE-infected and 547 (74%) CPE-colonized patients were identified. Few pediatric cases were identified (n = 18). Infection incidence rates remain low and stable (0.02 per 10,000 patient days in 2010 to 0.03 per 10,000 patient days in 2018), and colonization incidence rates have increased by 89% over the surveillance period. Overall, 92% of cases were acquired in a healthcare facility: 61% (n = 278) in a Canadian healthcare facility and 31% (n = 142) in a healthcare facility outside Canada. Of the 8% of cases not acquired in a healthcare facility, 50% (16 of 32) reported travel outside of Canada in the 12 months prior to positive culture. The distribution of carbapenemases varied by region; New Delhi metallo-B-lactamase (NDM) was dominant (59%) in western Canada and Klebsiella pneumoniae carbapenemase (KPC) (66%) in central Canada. NDM and class D carbapenemase OXA-48 were more commonly identified among those who traveled outside of Canada, whereas KPC was more commonly identified among patients without travel. In addition, 30-day all-cause mortality was 14% (25 of 181) among CPE infected patients and 32% (14 of 44) among those with bacteremia. Conclusions: CPE rates remain low in Canada; however, national surveillance data suggest that the increase in CPE in Canada is now being driven by local nosocomial transmission as well as travel and healthcare within endemic areas. Changes in screening practices may have contributed to the increase in colonizations; however, these data are currently lacking and will be collected moving forward. These data highlight the need to intensify surveillance and coordinate infection control measures to prevent further spread of CPE in Canadian acute-care hospitals.
Susy Hota reports contracted research for Finch Therapeutics. Allison McGeer reports funds to her institution for projects for which she is the principal investigator from Pfizer and Merck, as well as consulting fees from the following companies: Sanofi-Pasteur, Sunovion, GSK, Pfizer, and Cidara.
Background: Nosocomial central-line–associated bloodstream infections (CLABSIs) are an important cause of morbidity and mortality in hospitalized patients. CLABSI surveillance establishes rates for internal and external comparison, identifies risk factors, and allows assessment of interventions. Objectives: To determine the frequency of CLABSIs among adult patients admitted to intensive care units (ICUs) in CNISP hospitals and evaluate trends over time. Methods: CNISP is a collaborative effort of the Canadian Hospital Epidemiology Committee, the Association of Medical Microbiologists and Infectious Disease Canada and the Public Health Agency of Canada. Since 1995, CNISP has conducted hospital-based sentinel surveillance of healthcare-associated infections. Overall, 55 CNISP hospitals participated in ≥1 year of CLABSI surveillance. Adult ICUs are categorized as mixed ICUs or cardiovascular (CV) surgery ICUs. Data were collected using standardized definitions and collection forms. Line-day denominators for each participating ICU were collected. Negative-binomial regression was used to test for linear trends, with robust standard errors to account for clustering by hospital. We used the Fisher exact test to compare binary variables. Results: Each year, 28–42 adult ICUs participated in surveillance (27–37 mixed, 6–8 CV surgery). In both mixed ICUs and CV-ICUs, rates remained relatively stable between 2011 and 2018 (Fig. 1). In mixed ICUs, CLABSI rates were 1.0 per 1,000 line days in 2011, and 1.0 per 1,000 line days in 2018 (test for linear trend, P = .66). In CV-ICUs, CLABSI rates were 1.1 per 1,000 line days in 2011 and 0.8 per 1,000 line days in 2018 (P = .19). Case age and gender distributions were consistent across the surveillance period. The 30-day all-cause mortality rate was 29% in 2011 and in 2018 (annual range, 29%–35%). Between 2011 and 2018, the percentage of isolated microorganisms that were coagulase-negative staphylococci (CONS) decreased from 31% to 18% (P = .004). The percentage of other gram-positive organisms increased from 32% to 37% (P = .34); Bacillus increased from 0% to 4% of isolates and methicillin-susceptible Staphylococcus aureus from 2% to 6%). The gram-negative organisms increased from 21% to 27% (P = .19). Yeast represented 16% in 2011 and 18% in 2018; however, the percentage of yeast that were Candida albicans decreased over time (58% of yeast in 2011 and 30% in 2018; P = .04). Between 2011 and 2018, the most commonly identified species of microorganism in each year were CONS (18% in 2018) and Enterococcus spp (18% in 2018). Conclusions: Ongoing CLABSI surveillance has shown stable rates of CLABSI in adult ICUs from 2011 to 2018. The causative microorganisms have changed, with CONS decreasing from 31% to 18%.
Funding: CNISP is funded by the Public Health Agency of Canada.
Disclosures: Allison McGeer reports funds to her for studies, for which she is the principal investigator, from Pfizer and Merck, as well as consulting fees from Sanofi-Pasteur, Sunovion, GSK, Pfizer, and Cidara.
A 47-year-old homeless male presents to the emergency department (ED) with right lower extremity swelling, erythema and pain. He has diabetes mellitus, and had one prior episode of cellulitis three months ago affecting the same leg. He has a history of medication noncompliance. At triage, his temperature is 38.3°C but the remaining vital signs are unremarkable. On examination of the affected leg, there is an approximately 10 × 10 cm area of erythema, induration and increased warmth. There is mild tenderness to palpation and you wonder if there is a small degree of fluctuance. There is no lymphangitis, crepitus, necrosis or pain out of proportion to clinical findings.
To assess clinically relevant outcomes after complete cessation of control measures for vancomycin-resistant enterococci (VRE).
Quasi-experimental ecological study over 3.5 years.
All VRE screening and isolation practices at 4 large academic hospitals in Ontario, Canada, were stopped on July 1, 2012. In total, 618 anonymized abstracted charts of patients with VRE-positive clinical isolates identified between July 1, 2010, and December 31, 2013, were reviewed to determine whether the case was a true VRE infection, a VRE colonization or contaminant, or a true VRE bacteremia. All deaths within 30 days of the last VRE infection were also reviewed to determine whether the death was fully or partially attributable to VRE. All-cause mortality was evaluated over the study period. Generalized estimating equation methods were used to cluster outcome rates within hospitals, and negative binomial models were created for each outcome.
The incidence rate ratio (IRR) for VRE infections was 0.59 and the associated P value was .34. For VRE bacteremias, the IRR was 0.54 and P=.38; for all-cause mortality the IRR was 0.70 and P=.66; and for VRE attributable death, the IRR was 0.35 and P=.49. VRE control measures were not significantly associated with any of the outcomes. Rates of all outcomes appeared to increase during the 18-month period after cessation of VRE control measures, but none reached statistical significance.
Clinically significant VRE outcomes remain rare. Cessation of all control measures for VRE had no significant attributable adverse clinical impact.
Nematodes (roundworms) are the most common parasites infecting humans worldwide. Of almost half a million species of roundworms, approximately 60 are known to be pathogenic to humans. Among the most prevalent human infections are those due to the intestinal (lumen-dwelling) nematodes. Ascaris lumbricoides and Trichuris trichiura each infect over 1 billion people worldwide; hookworms (Ancylostoma duodenale and Necator americanus) infect almost the same number. Other important nematodes of humans include Strongyloides stercoralis and Enterobius vermicularis. Coinfection, in particular with A. lumbricoides and T. trichiura, is common.
Ascaris lumbricoides, hookworm, and T. trichiura, collectively referred to as geohelminths (or soil-transmitted helminths), share the requirement for eggs or larvae to mature in soil in order to be infective to humans. Due to this obligate soil stage of maturation, these parasites cannot be transmitted from person to person. In contrast, S. stercoralis is able to complete its entire life cycle within the human host, and like E. vermicularis, both person-to-person transmission and autoinfection can occur.
The majority of geohelminthic infections are asymptomatic and associated with low worm burdens, whereas the minority (15%–35%) of infected individuals harbor the majority of the worm burden and suffer from more intense symptoms. Geohelminthic infections are important contributors to growth retardation and cognitive delay in children, but conclusively proving the benefit of large-scale anthelminthic therapy in endemic areas is challenging for a number of reasons. Geohelminths are unaffected by host immune responses, leading to chronic infection if untreated, although the natural history of such infections (excluding hookworm) is usually one of decreasing worm burden over time; even with treatment, however, reinfection is common.
To identify the behavioral determinants—both barriers and enablers—that may impact physician hand hygiene compliance.
A qualitative study involving semistructured key informant interviews with staff physicians and residents.
An urban, 1,100-bed multisite tertiary care Canadian hospital.
A total of 42 staff physicians and residents in internal medicine and surgery.
Semistructured interviews were conducted using an interview guide that was based on the theoretical domains framework (TDF), a behavior change framework comprised of 14 theoretical domains that explain health-related behavior change. Interview transcripts were analyzed using thematic content analysis involving a systematic 3-step approach: coding, generation of specific beliefs, and identification of relevant TDF domains.
Similar determinants were reported by staff physicians and residents and between medicine and surgery. A total of 53 specific beliefs from 9 theoretical domains were identified as relevant to physician hand hygiene compliance. The 9 relevant domains were knowledge; skills; beliefs about capabilities; beliefs about consequences; goals; memory, attention, and decision processes; environmental context and resources; social professional role and identity; and social influences.
We identified several key determinants that physicians believe influence whether and when they practice hand hygiene at work. These beliefs identify potential individual, team, and organization targets for behavior change interventions to improve physician hand hygiene compliance.
Infect Control Hosp Epidemiol 2014;35(12):1511–1520
To determine trends, patient characteristics, and outcome of patients with healthcare-associated influenza in Canadian hospitals.
Prospective surveillance of laboratory-confirmed influenza among hospitalized adults was conducted from 2006 to 2012. Adults with positive test results at or after admission to the hospital were assessed. Influenza was considered to be healthcare associated if symptom onset was equal to or more than 96 hours after admission to a facility or if a patient was readmitted less than 96 hours after discharge or admitted less than 96 hours after transfer from another facility. Baseline characteristics of influenza patients were collected. Patients were reassessed at 30 days to determine the outcome.
Acute care hospitals participating in the Canadian Nosocomial Infection Surveillance Program.
A total of 570 (17.3%) of 3,299 influenza cases were healthcare associated; 345 (60.5%) were acquired in a long-term care facility (LTCF), and 225 (39.5%) were acquired in an acute care facility (ACF). There was year-to-year variability in the rate and proportion of cases that were healthcare associated and variability in the proportion that were acquired in a LTCF versus an ACF. Patients with LTCF-associated cases were older, had a higher proportion of chronic heart disease, and were less likely to be immunocompromised compared with patients with ACF-associated cases; there was no significant difference in 30-day all-cause and influenza-specific mortality.
Healthcare-associated influenza is a major component of the burden of disease from influenza in hospitals, but the proportion of cases that are healthcare associated varies markedly from year to year, as does the proportion of healthcare-associated infections that are acquired in an ACF versus an LTCF.
The objective of this study was to determine whether skin and soft tissue infections (SSTIs) caused by methicillin-resistant Staphylococcus aureus (MRSA) in patients presenting to The Ottawa Hospital emergency departments (TOHEDs) differed from SSTIs caused by methicillin-susceptible Staphylococcus aureus (MSSA) with regard to risk factors, management, and outcomes.
All patients seen at TOHEDs in 2006 and 2007 with SSTIs who yielded MRSA or MSSA in cultures from the site of infection were eligible for inclusion. We excluded patients with decubitus ulcers and infections related to diabetes or peripheral vascular disease. We used an unmatched case-control design. Cases were defined as patients with MRSA isolated from the infection site, and controls were defined as patients with MSSA isolated from the infection site. Data were collected retrospectively from health records and laboratory and hospital information systems.
A total of 153 patients were included in the study (81 cases and 72 controls). The mean age of cases was 37 years, compared to 47 years for the controls (p < 0.001). Cases were more likely to have transient residence (31% v. 3% [OR 15.6, 95% CI 3.9–61.8, p < 0.001]), present with abscesses (64% v. 15% [OR 9.9, 95% CI 4.3–23.7, p < .001]), have a documented history of hepatitis C infection (28% v. 3% [OR 13.9, 95% CI 3.9–55.0, p < 0.001]), and have a history of substance abuse (53% v. 10% [OR 10.5, 95% CI 4.4–25.1, p < 0.001]). Cases most commonly used crack cocaine and injection drugs.
SSTIs caused by MRSA at TOHEDs mainly occur in a population that is young and transient with comorbidities such as hepatitis C and substance abuse.
Surveillance for pandemic H1N1 influenza was conducted between June 1, 2009, and May 31, 2010, among adults at 40 participating hospitals in the Canadian Nosocomial Infection Surveillance Program. The first wave was characterized by a higher proportion of Aboriginals and pregnant women as well as severe outcomes, compared to the second wave.
Infect Control Hosp Epidemiol 2012;33(10):1043-1046
Most cases of necrotizing enterocolitis (NEC) are sporadic, but outbreaks in hospital settings suggest an infectious cause. Our neonatal intensive care unit (NICU) experienced an outbreak of methicillin-sensitive Staphylococcus aureus (MSSA). We aimed to assess whether the enhancement of infection prevention and control measures would be associated with a reduction in the number of cases of NEC.
Retrospective chart review.
A 24-bed, university-affiliated, inborn level 3 NICU.
Infants of less than 30 weeks gestation or birth weight ≤ 1,500 g admitted to the NICU between January 2007 and December 2008 were considered at risk of NEC. All cases of NEC were reviewed.
Infection prevention and control measures, including hand hygiene education, were enhanced during the outbreak. Avoidance of overcapacity in the NICU was reinforced, environmental services (ES) measures were enhanced, and ES hours were increased.
Two hundred eighty-two at-risk infants were admitted during the study. Their gestational age and birth weight (mean ± SD) were 28.2 ± 2.7 weeks and 1,031 ± 290 g, respectively. The proportion of NEC was 18/110 (16.4%) before the outbreak, 1/54 (1.8%) during the outbreak, and 4/118 (3.4%) after the outbreak. After adjustment for gestational age, birth weight, gender, and singleton versus multiple births, the proportion was lower in the postoutbreak period than in the preoutbreak period (P< .002).
Although this observational study cannot establish a causal relationship, there was a significant decrease in the incidence of NEC following implementation of enhanced infection prevention and control measures to manage an MSSA outbreak.
Numerous barriers to maintaining infection control practices through the use of personal protective equipment (PPE) exist in the emergency department (ED). This study examined the knowledge, self-reported behaviours, and barriers to compliance with infection control practices and the use of PPE in Canadian pediatric EDs.
A self-administered survey instrument consisting of 21 questions was developed and piloted for this study. The survey was mailed to all individuals listed in the Pediatric Emergency Research Canada database of physicians practicing pediatric emergency medicine in Canada.
A total of 186 physicians were surveyed, and 123 (66%) participated. Twenty-two percent of participants reported that they had never received PPE training and 32% had not been trained in the previous 2 years. Fifty-three percent reported being very or somewhat comfortable with their knowledge of transmission-based isolation practices. Participants were correct on a mean of 4.9 of 11 knowledge-based questions (SD 1.7). For scenarios assessing self-reported use of PPE, participants selected answers that reflected PPE use in accordance with national infection control standards in a mean of 1.0 of 6 scenarios (SD 1.0). Participants reported that they would be more likely to use PPE if patients were clearly identified prior to physician assessment, equipment was accessible, and PPE use was made a priority in their ED.
Knowledge and self-reported adherence to recommended infection control practices among Canadian pediatric emergency physicians is suboptimal. Early identification of patients requiring PPE, convenient access to PPE, and improved education regarding isolation and PPE practices may improve adherence.
Nematodes (roundworms) are the most common parasites infecting humans worldwide. Of almost half a million species of roundworms, approximately 60 are known to be pathogenic to humans. Among the most prevalent human infections are those due to the intestinal (lumen-dwelling) nematodes. Ascaris lumbricoides and Trichuris trichiura each infect over 1 billion people worldwide; hookworm (Ancylostoma duodenale and Necator americanus) infects almost the same number. Other important nematodes of humans include Strongyloides stercoralis and Enterobius vermicularis. Co-infection, in particular with A. lumbricoides and T. trichiura, is common.
Ascaris lumbricoides, hookworm, and T. trichiura, collectively referred to as geohelminths (or soil-transmitted helminths), share the requirement for eggs or larvae to mature in soil in order to be infective to humans. The majority of infections caused by these species are asymptomatic and associated with low worm burdens, whereas the minority (15%–35%) of infected individuals harbor the majority of the worm burden and suffer from more intense symptoms. The natural history of geohelminthic infections is usually one of decreasing worm burden over time. Due to the obligate soil stage of maturation, these parasites cannot be transmitted from person to person. In contrast, S. strongyloides is able to complete its entire life cycle within the human host, and like E. vermicularis, both person-to-person transmission and autoinfection can occur.
Email your librarian or administrator to recommend adding this to your organisation's collection.