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1.  Mandatory vaccination 
PMCID: PMC3735749  PMID: 23922359
2.  Effectiveness of neuraminidase inhibitors in preventing hospitalization during the H1N1 influenza pandemic in British Columbia, Canada 
In British Columbia (BC), Canada, neuraminidase inhibitors (NIs) were publicly funded during the 2009 A(H1N1)pdm09 pandemic for treatment of high-risk patients and/or anyone with moderate-to-severe illness. We assessed antiviral effectiveness (AVE) against hospitalization in that context.
A population-based cohort study was conducted using linked administrative data. The cohort included all individuals living in BC during the study period (1 September to 31 December 2009) with a diagnostic code consistent with influenza or pandemic H1N1. The main study period pertained to the second-wave A(H1N1)pdm09 circulation (1 October to 31 December 2009), with sensitivity analyses around the more specific pandemic peak (18 October to 7 November). Exposure was defined by same-day NI prescription. The main outcome was all-cause hospitalization within 14 days of the outpatient influenza diagnosis. Cox proportional hazards models assessed AVE with 1 : 1 propensity-score matching and covariate adjustment.
After matching, there were 304/58 061 NI-exposed and 345/58 061 unexposed patients hospitalized during the main study period. The very young [<6 months (35.0; 95% CI 16.7–73.4)], the old [65–79 years (13.7; 95% CI 10.1–18.6)] and the very old [≥80 years (38.7; 95% CI 26.6–56.5)] had the highest hospitalization rate per 1000 patients overall. Fully adjusted AVE against all-cause hospitalization during the main study period was 16% (95% CI 2%–28%), similar to the pandemic peak (15%; 95% CI −4%–30%).
The use of NIs was associated with modest protection against hospitalization during the 2009 pandemic, but appeared underutilized in affected age groups with the highest hospitalization risk.
PMCID: PMC3977606  PMID: 24346762
oseltamivir; zanamivir; antivirals; mortality; population-based; cohort
3.  Prion disease risk perception in Canadian medical laboratories 
There are no national guidelines specific for handling prion-associated specimens in Canadian medical laboratories. Medical laboratory workers may perceive themselves at risk of prion transmission and, on occasion, decline to process such specimens.
To examine the knowledge, attitudes and reported behaviours of medical laboratory workers in relation to prion disease to understand their risk perception and the need for national laboratory guidelines on prion infection control.
Survey development and cross-sectional web-based administration
The survey was developed through key informant interviews and a modified Delphi process. Medical laboratory workers across Canada were invited by laboratory managers and national organizations to complete the web-based survey.
Twelve key informant interviews were performed. Consensus for questionnaire content was reached through two rounds of the Delphi process. Responses were received from 426 Canadian medical laboratory workers; 37% of medical laboratory staff reported processing prion-associated specimens. Different protocols for specimen processing were followed, and 18% believed they were at risk when processing these specimens. Less than one-third of those receiving specimens believed they were adequately trained. The mean (±SD) knowledge score was 9.25±4.5/24; individuals who had received training scored significantly higher than those who were untrained (P<0.01). Eighty-one per cent of respondents would be more comfortable processing specimens if national guidelines existed and were used in their laboratory.
There is a high perception of risk and few perceived benefits of processing prion-associated specimens. National guidelines for prion infection control in medical laboratories and adequate training would enable medical laboratory workers to process these specimens efficiently and confidently.
PMCID: PMC3403661  PMID: 23730317
Delphi technique; Laboratory personnel; Prions; Risk; Specimen handling
4.  A brief tool to assess capacity to consent for medical care among homeless individuals with problematic substance use: study protocol 
Archives of Public Health  2013;71(1):11.
Public health care increasingly uses outreach models to engage individuals who are marginalized, many of whom misuse substances. Problematic substance use, together with marginalization from the health care system, among homeless adults makes it difficult to assess their capacity to consent to medical care. Tools have been developed to assess capacity to consent; however, these tools are lengthy and unsuitable for outreach settings. The primary objective of this study is to develop, validate, and pilot a brief but sensitive screening instrument which can be used to guide clinicians in assessing capacity to consent in outreach settings. The goal of this paper is to outline the protocol for the development of such a tool.
A brief assessment tool will be developed and compared to the MacArthur Competency Assessment Tool for Treatment (MacCAT-T). As list of 36 possible questions will be created by using qualitative data from clinician interviews, as well as concepts from the literature. This list will be rated by content experts according to the extent that it corresponds to the test objectives. The instrument will be validated with 300 homeless adult volunteers who self-report problematic substance use. Participants will be assessed for capacity using the MacCAT-T and the new instrument. A combination of Classical Test Theory and advanced psychometric methods will be used for the psychometric analysis. Corrected Item-Total correlation will be examined to identify items that discriminate poorly. Guided exploratory factor analysis will be conducted on the final selection of items to confirm the assumptions for a unidimensional polytomous Rasch model. If unidimensionality is confirmed, an unstandardized Cronbach Alpha will be calculated. If multi-dimensionality is detected, a multidimensional Rasch analysis will be conducted. Results from the new instrument will be compared to the total score from the MacCAT-T by using Pearson’s correlation test. The new instrument will then be piloted in real-time by street outreach clinicians to determine the acceptability and usefulness of the new instrument.
This research will build on the existing knowledge about assessing capacity to consent and will contribute new knowledge about assessing individuals whose judgment is impaired by substance use.
PMCID: PMC3651044  PMID: 23651056
Capacity to consent; Substance use; Psychometric instruments; Vulnerable populations
5.  Lyme disease 
Canadian Family Physician  2012;58(5):e289-e295.
To determine physicians’ level of awareness and knowledge of Lyme disease (LD) in a low-prevalence area and whether physicians’ practices align with current guidelines for treatment of LD.
A 23-item questionnaire assessing demographic characteristics, general knowledge about LD, laboratory testing for LD, and responses to 3 clinical scenarios.
British Columbia (BC).
Pediatricians, FPs, and internal medicine specialists who were licensed to practise in BC.
Main outcome measures
Knowledge of signs and symptoms of LD, beliefs about risk of LD, attitudes toward LD in patients in their practices, and application of accepted practice guidelines for the treatment of LD in clinical scenarios.
Overall, 80.6% of respondents were FPs. Average knowledge score was 72.5% for FPs and 75.0% for other specialists. Most respondents (75.6% of FPs and 71.8% of other specialists) underestimated the occurrence of erythema migrans (EM), and only 26.1% and 28.3%, respectively, knew that EM alone was diagnostic for LD. A total of 30.5% of FPs and 12.1% of other specialists reported having treated a patient for the disease despite not believing that the patient had LD. Of all the respondents, 62.1% knew that LD was a reportable disease in BC. Respondents’ reports of risk of LD in their areas were appropriately associated with actual risk based on ecological niche.
Physicians are knowledgeable about the clinical signs and symptoms of LD and aware of the risk of the disease despite being in a low-endemic area. Physicians in BC are comfortable with treating patients empirically for LD. Education is needed to inform physicians that EM is diagnostic and no laboratory testing is indicated before treatment. Raising awareness among physicians that LD is reportable might improve reporting of future cases.
PMCID: PMC3352816  PMID: 22734172
6.  Evaluation of the Do Bugs Need Drugs? program in British Columbia: Can we curb antibiotic prescribing? 
Antibiotic resistance is accelerated by the overuse of antibiotics. Do Bugs Need Drugs? is an educational program adapted in British Columbia to target both the public and health care professionals, with the aim of reducing unnecessary prescribing. The current article presents a descriptive evaluation of the impact of the program over the first four years.
Program implementation was measured by the amount of educational material distributed and the level of participation in educational sessions. The impact of the program was assessed by measuring changes in knowledge and prescribing habits of participating physicians, and by investigating provincial trends in antibiotic use.
A total of 51,367 children, assisted-living residents and health care professionals have participated in the program since its inception in the fall of 2005. Pre- and postcourse assessments of participating physicians indicated significant improvements in clinical knowledge and appropriate antibiotic treatment of upper respiratory tract infections. Overall rates of antibiotic use in the province have stabilized since 2006. The rates of consumption of fluoroquinolones and macrolides have levelled off since 2005. Utilization rates for acute bronchitis are at the same level as when the program was first implemented, but rates for other acute upper respiratory tract infections of interest have declined.
The Do Bugs Need Drugs? program significantly improves physician antibiotic prescription decisions and is ecologically associated with desirable change in population antibiotic consumption patterns.
PMCID: PMC3076151  PMID: 22379484
Antibiotics; Community education; Program evaluation; Utilization
7.  Establishing a community of practice of researchers, practitioners, policy-makers and communities to sustainably manage environmental health risks in Ecuador 
The Sustainably Managing Environmental Health Risk in Ecuador project was launched in 2004 as a partnership linking a large Canadian university with leading Cuban and Mexican institutes to strengthen the capacities of four Ecuadorian universities for leading community-based learning and research in areas as diverse as pesticide poisoning, dengue control, water and sanitation, and disaster preparedness.
In implementing curriculum and complementary innovations through application of an ecosystem approach to health, our interdisciplinary international team focused on the question: “Can strengthening of institutional capacities to support a community of practice of researchers, practitioners, policy-makers and communities produce positive health outcomes and improved capacities to sustainably translate knowledge?” To assess progress in achieving desired outcomes, we review results associated with the logic framework analysis used to guide the project, focusing on how a community of practice network has strengthened implementation, including follow-up tracking of program trainees and presentation of two specific case studies.
By 2009, train-the-trainer project initiation involved 27 participatory action research Master’s theses in 15 communities where 1200 community learners participated in the implementation of associated interventions. This led to establishment of innovative Ecuadorian-led master’s and doctoral programs, and a Population Health Observatory on Collective Health, Environment and Society for the Andean region based at the Universidad Andina Simon Bolivar. Building on this network, numerous initiatives were begun, such as an internationally funded research project to strengthen dengue control in the coastal community of Machala, and establishment of a local community eco-health centre focusing on determinants of health near Cuenca.
Strengthening capabilities for producing and applying knowledge through direct engagement with affected populations and decision-makers provides a fertile basis for consolidating capacities to act on a larger scale. This can facilitate the capturing of benefits from the “top down” (in consolidating institutional commitments) and the “bottom up” (to achieve local results).
Alliances of academic and non-academic partners from the South and North provide a promising orientation for learning together about ways of addressing negative trends of development. Assessing the impacts and sustainability of such processes, however, requires longer term monitoring of results and related challenges.
PMCID: PMC3247836  PMID: 22165915
8.  West Nile Virus Range Expansion into British Columbia 
Emerging Infectious Diseases  2010;16(8):1251-1258.
Elevated temperatures and mosquito abundance may contribute.
In 2009, an expansion of West Nile virus (WNV) into the Canadian province of British Columbia was detected. Two locally acquired cases of infection in humans and 3 cases of infection in horses were detected by ELISA and plaque-reduction neutralization tests. Ten positive mosquito pools were detected by reverse transcription PCR. Most WNV activity in British Columbia in 2009 occurred in the hot and dry southern Okanagan Valley. Virus establishment and amplification in this region was likely facilitated by above average nightly temperatures and a rapid accumulation of degree-days in late summer. Estimated exposure dates for humans and initial detection of WNV-positive mosquitoes occurred concurrently with a late summer increase in Culex tarsalis mosquitoes (which spread western equine encephalitis) in the southern Okanagan Valley. The conditions present during this range expansion suggest that temperature and Cx. tarsalis mosquito abundance may be limiting factors for WNV transmission in this portion of the Pacific Northwest.
PMCID: PMC3298306  PMID: 20678319
West Nile virus; arbovirus; Canada; British Columbia; insect vectors; arthropod vectors; ecology; zoonoses; epidemiology; research
9.  Risk Factors for SARS Transmission from Patients Requiring Intubation: A Multicentre Investigation in Toronto, Canada 
PLoS ONE  2010;5(5):e10717.
In the 2003 Toronto SARS outbreak, SARS-CoV was transmitted in hospitals despite adherence to infection control procedures. Considerable controversy resulted regarding which procedures and behaviours were associated with the greatest risk of SARS-CoV transmission.
A retrospective cohort study was conducted to identify risk factors for transmission of SARS-CoV during intubation from laboratory confirmed SARS patients to HCWs involved in their care. All SARS patients requiring intubation during the Toronto outbreak were identified. All HCWs who provided care to intubated SARS patients during treatment or transportation and who entered a patient room or had direct patient contact from 24 hours before to 4 hours after intubation were eligible for this study. Data was collected on patients by chart review and on HCWs by interviewer-administered questionnaire. Generalized estimating equation (GEE) logistic regression models and classification and regression trees (CART) were used to identify risk factors for SARS transmission.
45 laboratory-confirmed intubated SARS patients were identified. Of the 697 HCWs involved in their care, 624 (90%) participated in the study. SARS-CoV was transmitted to 26 HCWs from 7 patients; 21 HCWs were infected by 3 patients. In multivariate GEE logistic regression models, presence in the room during fiberoptic intubation (OR = 2.79, p = .004) or ECG (OR = 3.52, p = .002), unprotected eye contact with secretions (OR = 7.34, p = .001), patient APACHE II score ≥20 (OR = 17.05, p = .009) and patient Pa02/Fi02 ratio ≤59 (OR = 8.65, p = .001) were associated with increased risk of transmission of SARS-CoV. In CART analyses, the four covariates which explained the greatest amount of variation in SARS-CoV transmission were covariates representing individual patients.
Close contact with the airway of severely ill patients and failure of infection control practices to prevent exposure to respiratory secretions were associated with transmission of SARS-CoV. Rates of transmission of SARS-CoV varied widely among patients.
PMCID: PMC2873403  PMID: 20502660
10.  Who is conflicted about handwashing? 
PMCID: PMC2780495  PMID: 19933816
11.  SARS among Critical Care Nurses, Toronto 
Emerging Infectious Diseases  2004;10(2):251-255.
To determine factors that predispose or protect healthcare workers from severe acute respiratory syndrome (SARS), we conducted a retrospective cohort study among 43 nurses who worked in two Toronto critical care units with SARS patients. Eight of 32 nurses who entered a SARS patient’s room were infected. The probability of SARS infection was 6% per shift worked. Assisting during intubation, suctioning before intubation, and manipulating the oxygen mask were high-risk activities. Consistently wearing a mask (either surgical or particulate respirator type N95) while caring for a SARS patient was protective for the nurses, and consistent use of the N95 mask was more protective than not wearing a mask. Risk was reduced by consistent use of a surgical mask, but not significantly. Risk was lower with consistent use of a N95 mask than with consistent use of a surgical mask. We conclude that activities related to intubation increase SARS risk and use of a mask (particularly a N95 mask) is protective.
PMCID: PMC3322898  PMID: 15030692
SARS; severe acute respiratory syndrome; critical care; risk factors; respiratory protective devices; masks; intubation; nursing; infection control
12.  Interpretation of diagnostic laboratory tests for severe acute respiratory syndrome: the Toronto experience 
An outbreak of severe acute respiratory syndrome (SARS) began in Canada in February 2003. The initial diagnosis of SARS was based on clinical and epidemiological criteria. During the outbreak, molecular and serologic tests for the SARS-associated coronavirus (SARS-CoV) became available. However, without a “gold standard,” it was impossible to determine the usefulness of these tests. We describe how these tests were used during the first phase of the SARS outbreak in Toronto and offer some recommendations that may be useful if SARS returns.
We examined the results of all diagnostic laboratory tests used in 117 patients admitted to hospitals in Toronto who met the Health Canada criteria for suspect or probable SARS. Focusing on tests for SARS-CoV, we attempted to determine the optimal specimen types and timing of specimen collection.
Diagnostic test results for SARS-CoV were available for 110 of the 117 patients. SARS-CoV was detected by means of reverse-transcriptase polymerase chain reaction (RT-PCR) in at least one specimen in 59 (54.1%) of 109 patients. Serologic test results of convalescent samples were positive in 50 (96.2%) of 52 patients for whom paired serum samples were collected during the acute and convalescent phases of the illness. Of the 110 patients, 78 (70.9%) had specimens that tested positive by means of RT-PCR, serologic testing or both methods. The proportion of RT-PCR test results that were positive was similar between patients who met the criteria for suspect SARS (50.8%, 95% confidence interval [CI] 38.4%–63.2%) and those who met the criteria for probable SARS (58.0%, 95% CI 44.2%–70.7%). SARS-CoV was detected in nasopharyngeal swabs in 33 (32.4%) of 102 patients, in stool specimens in 19 (63.3%) of 30 patients, and in specimens from the lower respiratory tract in 10 (58.8%) of 17 patients.
These findings suggest that the rapid diagnostic tests in use at the time of the initial outbreak lack sufficient sensitivity to be used clinically to rule out SARS. As tests for SARS-CoV continue to be optimized, evaluation of the clinical presentation and elucidation of a contact history must remain the cornerstone of SARS diagnosis. In patients with SARS, specimens taken from the lower respiratory tract and stool samples test positive by means of RT-PCR more often than do samples taken from other areas.
PMCID: PMC305313  PMID: 14707219
13.  Investigation of a nosocomial outbreak of severe acute respiratory syndrome (SARS) in Toronto, Canada 
Severe acute respiratory syndrome (SARS) was introduced into Canada by a visitor to Hong Kong who returned to Toronto on Feb. 23, 2003. Transmission to a family member who was later admitted to a community hospital in Toronto led to a large nosocomial outbreak. In this report we summarize the preliminary results of the epidemiological investigation into the transmission of SARS between 128 cases associated with this hospital outbreak.
We collected epidemiologic data on 128 probable and suspect cases of SARS associated with the hospital outbreak, including those who became infected in hospital and the next generation of illness arising among their contacts. Incubation periods were calculated based on cases with a single known exposure. Transmission chains from the index family to hospital contacts and within the hospital were mapped. Attack rates were calculated for nurses in 3 hospital wards where transmission occurred.
The cases ranged in age from 21 months to 86 years; 60.2% were female. Seventeen deaths were reported (case-fatality rate 13.3%). Of the identified cases, 36.7% were hospital staff. Other cases were household or social contacts of SARS cases (29.6%), hospital patients (14.1%), visitors (14.1%) or other health care workers (5.5%). Of the 128 cases, 120 (93.8%) had documented contact with a SARS case or with a ward where there was a known SARS case. The remaining 8 cases without documented exposure are believed to have had exposure to an unidentified case and remain under investigation. The attack rates among nurses who worked in the emergency department, intensive care unit and coronary care unit ranged from 10.3% to 60.0%. Based on 42 of the 128 cases with a single known contact with a SARS case, the mean incubation period was 5 days (range 2 to 10 days).
Evidence to date suggests that SARS is a severe respiratory illness spread mainly by respiratory droplets. There has been no evidence of further transmission within the hospital after the elapse of 2 full incubation periods (20 days).
PMCID: PMC180651  PMID: 12925421
14.  Outbreak of Escherichia coli 0157:H7 related to animal contact at a petting zoo 
To determine the cause of an outbreak of Escherichia coli 0157:H7 related to animal exposures so that further transmission could be prevented.
Description of laboratory investigations and a case control study.
Agricultural pavilion at an annual fair in Ontario.
People with laboratory evidence of E coli 0157:H7 (seven people) and others with diarrhea (155 people) who called the health unit following a media release were interviewed. Animals that were accessed most frequently by the public in the agriculture pavilion were tested for E coli 0157:H7. In the case control study, a case was defined as someone with laboratory confirmed E coli 0157:H7, or someone who developed severe or bloody diarrhea two to eight days after attending the agricultural pavilion at the fair (61 people). A convenience sample of people who attended the agricultural pavilion but did not develop diarrhea was selected as the control group (89 people).
Human and animal E coli 0157:H7 specimens were subtyped. Cases and controls were interviewed using a standardized questionnaire.
Subtyping of the seven human isolates of E coli 0157:H7 revealed five that were of an extremely uncommon phage type. Three samples from goats and one from sheep at the petting zoo in the agricultural pavilion were of this same phage type. The case control study also implicated goats (odds ratio [OR] 3.65; 95% CI 1.63 to 8.52) and sheep (OR 2.94; 95% CI 1.33 to 6.57) from the petting zoo.
Results of this investigation suggest strongly that the goats and sheep from the petting zoo were the source of this outbreak of E coli 0157:H7.
PMCID: PMC2094871  PMID: 18159389
Animal exhibit; Escherichia coli 0157:H7; Goats; Goats; Petting zoo; Sheep
15.  Use of Neo-melubrina, a banned antipyretic drug, in San Diego, California: a survey of patients and providers 
Western Journal of Medicine  2001;175(3):159-163.
Background Dipyrone is an antipyretic drug that has been associated with agranulocytosis. It is banned in the United States but is available in Mexico under the name Neo-melubrina. Objectives To define the use of Neo-melubrina in the Hispanic population of 2 San Diego, California, community clinics and to determine local physicians' and nurse practitioners' awareness of the drug and its risks. Design Patient survey and provider survey. Participants Patients: 200 parents of Hispanic pediatric patients. Providers: members of San Diego chapters of the American Academy of Pediatrics, the American Academy of Family Physicians, and the California Coalition of Nurse Practitioners. Main outcome measures Self-reported use of Neo-melubrina by patients, and provider awareness of Neo-melubrina and its most significant side effects. Results Of the 200 patients, 76 (38.0%) reported a lifetime use of Neo-melubrina. Most (56%) used it for both pain and fever. Most providers were unable to correctly identify why Neo-melubrina might be used or its adverse effects. Physicians answered correctly more often than nurse practitioners and pediatric providers more often than family medicine providers. Providers who trained within 75 miles of the US-Mexico border, who reported a patient population of more than 50% Hispanic, and who were resident physicians at the time of the survey were most likely to answer correctly. Conclusions Neo-melubrina has been used by a substantial percentage of Hispanic patients in the community clinics surveyed. Many San Diego health care providers are unaware of this medication and may, therefore, miss opportunities to educate patients about safer alternatives.
PMCID: PMC1071527  PMID: 11527837

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