Changes in vascular accesses and in incidence rates of dialysis-related bloodstream infections in Québec, Canada, 2011-2017.

OBJECTIVE: Surveillance of dialysis-related bloodstream infections (DRBSIs) has been mandatory in Québec since April 2011. The aim of this study was to describe the epidemiology of DRBSIs in Québec. METHODS: Cohort study of prevalent patients undergoing chronic dialysis in the 36 facilities that participated without interruption in the provincial surveillance, between April 2011 and March 2017. Two indicators were analyzed: proportion of patient months dialyzed using a fistula (a patient month is a 28-day cycle during which an individual patient received dialysis) and incidence rate of DRBSI. Binomial and Poisson regression with generalized estimating equations were used to describe the evolution of indicators over time and to quantify the association between facilities' proportion of fistulas and their incidence rate. RESULTS: Globally, 42.6% of all patient months were dialyzed using a fistula, but there was a statistically significant decrease over time (46.2% in 2011-2012 to 39.3% in 2016-2017). Despite this decline in the use of fistulas, rates of DRBSIs have also decreased, going from 0.38 DRBSIs per 100 patient months in 2011-2012 to 0.23 DRBSIs per 100 patient months in 2016-2017. No association was found between facility use of fistulas and the rate of DRBSI. At the individual level, however, the DRBSI rate was 4.12 times higher for patients using a catheter. CONCLUSIONS: In Québec, the rate of DRBSIs has decreased over a 6-year period despite an increasing proportion of patients dialyzed by catheter.

Healthcare-associated bloodstream infection trends under a provincial surveillance program.

OBJECTIVE: BACTOT, Quebec's healthcare-associated bloodstream infection (HABSI) surveillance program has been operating since 2007. In this study, we evaluated the changes in HABSI rates across 10 years of BACTOT surveillance under a Bayesian framework. DESIGN: A retrospective, cohort study of eligible hospitals having participated in BACTOT for at least 3 years, regardless of their entry date. Multilevel Poisson regressions were fitted independently for cases of HABSI, catheter-associated bloodstream infections (CA-BSIs), non-catheter-associated primary BSIs (NCA-BSIs), and BSIs secondary to urinary tract infections (BSI-UTIs) as the outcome and log of patient days as the offset. The log of the mean Poisson rate was decomposed as the sum of a surveillance year effect, period effect, and hospital effect. The main estimate of interest was the cohort-level rate in years 2-10 of surveillance relative to year 1. RESULTS: Overall, 17,479 cases and 33,029,870 patient days were recorded for the cohort of 77 hospitals. The pooled 10-year HABSI rate was 5.20 per 10,000 patient days (95% CI, 5.12-5.28). For HABSI, CA-BSI, and BSI-UTI, there was no difference between the estimated posterior rates of years 2-10 compared to year 1. The posterior means of the NCA-BSI rate ratios increased from the seventh year until the tenth year, when the rate was 29% (95% confidence interval, 1%-89%) higher than the first year rate. CONCLUSIONS: HABSI rates and those of the most frequent subtypes remained stable over the surveillance period. To achieve reductions in incidence, we recommend that more effort be expended in active interventions against HABSI alongside surveillance.

A ten-year review of healthcare-associated bloodstream infections from forty hospitals in Québec, Canada.

OBJECTIVE: Healthcare-associated bloodstream infections (HABSI) are a significant cause of morbidity and mortality worldwide. In Québec, Canada, HABSI arising from acute-care hospitals have been monitored since April 2007 through the Surveillance des bactériémies nosocomiales panhospitalières (BACTOT) program, but this is the first detailed description of HABSI epidemiology. METHODS: This retrospective, descriptive study was conducted using BACTOT surveillance data from hospitals that participated continuously between April 1, 2007, and March 31, 2017. HABSI cases and rates were stratified by hospital type and/or infection source. Temporal trends of rates were analyzed by fitting generalized estimating equation Poisson models, and they were stratified by infection source. RESULTS: For 40 hospitals, 13,024 HABSI cases and 23,313,959 patient days were recorded, for an overall rate of 5.59 per 10,000 patient days (95% CI, 5.54-5.63). The most common infection sources were catheter-associated BSIs (23.0%), BSIs secondary to a urinary focus (21.5%), and non-catheter-associated primary BSIs (18.1%). Teaching hospitals and nonteaching hospitals with ICUs often had rates higher than nonteaching hospitals without ICUs. Annual HABSI rates did not exhibit statistically significant changes from year to year. Non-catheter-associated primary BSIs were the only HABSI type that exhibited a sustained change across the 10 years, increasing from 0.69 per 10,000 patient days (95% CI, 0.59-0.80) in 2007-2008 to 1.42 per 10,000 patient days (95% CI, 1.27-1.58) in 2016-2017. CONCLUSIONS: Despite ongoing surveillance, overall HABSI rates have not decreased. The effect of BACTOT participation should be more closely investigated, and targeted interventions along alternative surveillance modalities should be considered, prioritizing high-burden and potentially preventable BSI types.

Hospital-Acquired Methicillin-Resistant Staphylococcus aureus Bloodstream Infections in Québec: Impact of Guidelines.

OBJECTIVE We examined the impact of methicillin-resistant Staphylococcus aureus (MRSA) guidelines in Québec adult hospitals from January 1, 2006, to March 31, 2015, by examining the incidence rate reduction (IRR) in healthcare-associated MRSA bloodstream infections (HA-MRSA), using central-line associated bloodstream infections (CLABSIs) as a comparator. METHODS In this study, we utilized a quasi-experimental design with Poisson segmented regression to model HA-MRSA and CLABSI incidence for successive 4-week surveillance segments, stratified by teaching status. We used 3 distinct periods with 2 break points (April 1, 2007, and January 3, 2010) corresponding to major MRSA guideline publications and updates. RESULTS Over the study period, HA-MRSA incidence decreased significantly in adult teaching facilities but not in nonteaching facilities. Prior to MRSA guideline publication (2006-2007), HA-MRSA incidence decrease was not significant (P=.89), while CLABSI incidence decreased by 4% per 4-week period (P=.05). After the publication of guidelines (2007-2009), HA-MRSA incidence decreased significantly by 1% (P=.04), while no significant decrease in CLABSI incidence was observed (P=.75). HA-MRSA and CLABSI decreases were both significant at 1% for 2010-2015 (P<.001 and P=.01, respectively). These decreases were gradual rather than sudden; break points were not significant. Teaching facilities drove these decreases. CONCLUSION During the study period, HA-MRSA and CLABSI rates decreased significantly. In 2007-2009, the significant decrease in HA-MRSA rates with stable CLABSI rates suggests an impact from MRSA-specific guidelines. In 2010-2015, significant and equal IRRs for HA-MRSA and CLABSI may be due to the continuing impact of MRSA guidelines, to the impact of new interventions targeting device-associated infections in general by the 2010-2015 Action Plan, or to a combination of factors. Infect Control Hosp Epidemiol 2017;38:840-847.

Central-Line-Associated Bloodstream Infections in Québec Intensive Care Units: Results from the Provincial Healthcare-Associated Infections Surveillance Program (SPIN).

BACKGROUND Following implementation of bundled practices in 2009 in Quebec and Canadian intensive care units (ICUs), we describe CLABSI epidemiology during the last 8 years in the province of Québec (Canada) and compare rates with Canadian and American benchmarks. METHODS CLABSI incidence rates (IRs) and central venous catheter utilization ratios (CVCURs) by year and ICU type were calculated using 2007-2014 data from the Surveillance Provinciale des Infections Nosocomiales (SPIN) program. Using American and Canadian surveillance data, we compared SPIN IRs to rates in other jurisdictions using standardized incidence ratios (SIRs). RESULTS In total, 1,355 lab-confirmed CLABSIs over 911,205 central venous catheter days (CVC days) were recorded. The overall pooled incidence rate (IR) was 1.49 cases per 1,000 CVC days. IRs for adult teaching ICUs, nonteaching ICUs, neonatal ICUs (NICUs), and pediatric ICUs (PICUs) were 1.04, 0.91, 4.20, and 2.15 cases per 1,000 CVC days, respectively. Using fixed SPIN 2007-2009 benchmarks, CLABSI rates had decreased significantly in all ICUs except for PICUs by 2014. Rates declined by 55% in adult teaching ICUs, 52% in adult nonteaching ICUs, and 38% in NICUs. Using dynamic American and Canadian CLABSI rates as benchmarks, SPIN adult teaching ICU rates were significantly lower and adult nonteaching ICUs had lower or comparable rates, whereas NICU and PICU rates were higher. CONCLUSION Québec ICU CLABSI surveillance shows declining CLABSI rates in adult ICUs. The absence of a decrease in CLABSI rate in NICUs and PICUs highlights the need for continued surveillance and analysis of factors contributing to higher rates in these populations. Infect Control Hosp Epidemiol 2016;1-9.

Survey of infection control practices in hemodialysis units: preventing vascular access-associated bloodstream infections.

OBJECTIVE: Despite surveillance, the Quebec Healthcare-Associated Infections Surveillance Program saw no improvement in vascular access-associated bloodstream infections in hemodialysis (HD). We aimed to determine the infection control measures recommended and implemented in Quebec's HD units, compliance of local protocols to infection control practice guidelines, and reasons behind the low prevalence of arteriovenous fistulas. METHODS: An online survey was elaborated on the basis of the Centers for Disease Control and Prevention (CDC) and National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines. The questionnaire was validated (construct, content, face validity, and reliability) and sent to all HD units in Quebec (n = 40). Results were analyzed using descriptive statistics, linear regression, and Poisson regression. RESULTS: Thirty-seven (93%) of 40 HD units participated. Thirty (94%) of the 32 centers where central catheters are inserted have written insertion protocols. Compliance with practice guidelines is good, except for full-body draping during catheter insertion (79%) and ointment use at insertion site (3%). Prevention measures for catheter maintenance are in accordance with guidelines, except for skin disinfection with at least 0.5% chlorhexidine and 70% alcohol (67% compliance) and regular antiseptic ointment use at the insertion site (3%). Before fistula cannulation, skin preparation is suboptimal; forearm hygiene is performed in only 61% of cases. Several factors explain the low rate of fistulas, including patient preference (69%) and lack of surgical resources (39%; P = .01). CONCLUSIONS: Improvement in standardization of care according to practice guidelines is necessary. Fistula rate could be increased by improving access to surgical resources and patient education. Strategies are now being elaborated to address these findings.

Accuracy of physician reporting in routine public health surveillance for hepatitis C virus infection.

OBJECTIVE: From January 2007 to December 2008, the Montréal Public Health Department sent postal questionnaires to physicians and conducted patient interviews for all those newly diagnosed with hepatitis C virus (HCV) infection. We evaluated physician responses to risk factor questions for non-acute HCV cases. METHODS: We compared physician and patient responses with each of nine risk factor questions, determined the sensitivity and specificity of physician responses compared with patient responses, and evaluated agreement using Gwet's agreement coefficient (AC1). We ranked risk factors and compared the distributions by principal exposure category according to physician reporting vs. patient interview using the Chi-square test. RESULTS: The completeness of physicians' responses (yes, no, or unknown) varied by risk factor question from 90.8% to 96.7%. For risk factors present among more than 5% of cases, sensitivity of physician responses ranged from 26.9% to 87.7% and specificity ranged from 93.0% to 98.6%. The AC1 coefficients for agreement between physician and patient responses to lifetime risk factors considered most important in HCV acquisition were 0.80 for injection drug use, 0.95 for blood transfusion before 1990, and 0.86 for birth in a country with high HCV prevalence. Risk distributions by principal exposure category according to physician reporting vs. patient interview were not statistically different (χ(2)[4] = 2.17, p=0.704). CONCLUSION: Postal questionnaires completed by physicians appear valid for determining the principal exposure category among non-acute HCV cases. Physician reporting can be a useful and low-cost component of routine HCV surveillance.

A survey of preventive measures used and their impact on central line-associated bloodstream infections (CLABSI) in intensive care units (SPIN-BACC).

BACKGROUND: The Quebec central line-associated bloodstream infections (CLABSI) in intensive care units (ICUs) Surveillance Program saw a decrease in CLABSI rates in most ICUs. Given the surveillance trends observed in recent years, we aimed to determine what preventive measures have been implemented, if compliance to measures was monitored and its impact on CLABSI incidence rates. METHODS: All hospitals participating in the Quebec healthcare-associated infections surveillance program (SPIN-BACC - n = 48) received a 77-question survey about preventive measures implemented and monitored in their ICU. The questionnaire was validated for construct, content, face validity, and reliability. We used Poisson regression to measure the association between compliance monitoring to preventive measures and CLABSI rates. RESULTS: Forty-two (88%) eligible hospitals completed the survey. Two components from the maximum barrier precautions were used less optimally: cap (88%) and full sterile body drape (71%). Preventive measures reported included daily review of catheter need (79%) and evaluation of insertion site for the presence of inflammation (90%). Two hospitals rewired lines even if an infection was suspected or documented.In adult ICUs, there was a statistically significant greater decrease in CLABSI rates in ICUs that monitored compliance to preventive insertion measures, after adjusting for teaching status and the number of hospital beds (p = 0.036). CONCLUSIONS: Hospitals participating to the SPIN-BACC program follow recommendations for CLABSI prevention, but only a minority locally monitor their application. Compliance monitoring of preventive measures for catheter insertion was associated with a decrease in CLABSI incidence rates.

Central line-associated bloodstream infection in neonatal intensive care units.

OBJECTIVE: Describe the epidemiology of central line-associated bloodstream infections (CLABSIs) in neonatal intensive care units (NICUs) participating in a standardized and mandatory CLABSI surveillance program. DESIGN: Retrospective cohort. Setting. We included patients admitted (April 2007-March 2011) to 7 level II/III NICUs who developed a CLABSI (as defined by the National Healthcare Safety Network). METHODS: CLABSIs/1,000 central line-days and device utilization ratio were calculated; χ(2) test, Student t test, Kruskal-Wallis, and Poisson regression were used. RESULTS: Overall, 191 patients had 202 CLABSI episodes for a pooled mean rate of 4.0 CLABSIs/1,000 central line-days and a device utilization ratio of 0.20. Annual pooled mean CLABSI rates increased from 3.6 in 2007-2008 to 5.1 CLABSIs/1,000 central line-days in 2010-2011 (P - .01). The all-cause 30-day case fatality proportion was 8.9% (n = 17) and occurred a median of 8 days after CLABSI. Coagulase-negative Staphylococcus was identified in 112 (50.5%) cases. Staphylococcus aureus was identified in 22 cases, and 3 (13.6%) were resistant to methicillin. An underlying intra-abdominal pathology was found in 20% (40/202) of CLABSI cases, 50% of which were reported in the last year of study. When adjusted for mean birth weight, annual CLABSI incidence rates were independently associated with the proportion of intra-abdominal pathology (P = .007) and the proportion of pulmonary pathology (P = .016) reported. CONCLUSION: The increase in CLABSI rates in Quebec NICUs seems to be associated with an increased proportion of cases with underlying intra-abdominal and pulmonary pathologies, which needs further investigation.

Sexual health of adolescents in Quebec residential Youth Protection Centres.

OBJECTIVES: To document risk behaviours and prevalence of chlamydia and gonorrhoea infections among adolescents aged 14 to 17 years entering care in Quebec Youth Protection Centres (YPC). METHODS: From July 2008 to May 2009, adolescents residing in six YPCs completed a questionnaire during a face-to-face interview. Questions covered sexual and substance use behaviours prior to admission, as well as other health issues affecting respondents' mental and physical health. Urine samples were tested for Chlamydia trachomatis genital infection (CTGI) and Neisseria gonorrhoea genital infection (NGGI). RESULTS: Among 578 participants aged 14 to 17 years, 89% had had consensual sexual relations. Sexual risk behaviours included early sexual initiation (66% at <14 years); multiple partners (median lifetime number: girls 5, boys 8); 50% or more of sexual relations under the influence of drugs or alcohol (girls 43%, boys 48%); group sex (girls 38%, boys 43%); and sex in exchange for money or other goods (girls 27%, boys 8%). Only a quarter of boys and girls used double protection (condom and a contraceptive method) during the most recent vaginal relation. A history of pregnancy was reported by 28% of girls. Prevalence of CTGI was 9.3% (CI: 5.5-14.5) among girls and 1.9% (CI: 0.6-4.4) among boys. Prevalence of NGGI gonorrhoea was 1.7% (CI: 0.3-4.8) among girls and 0% (CI: 0.0-1.4) among boys.In multivariate analyses, factors significantly associated with chlamydia infection among sexually active girls were: hospitalization for alcohol intoxication; and a history of suicidal ideation with plan. CONCLUSION: Sexual risk behaviours are common among adolescents entering YPCs, resulting in high levels of chlamydia infection. Mental health issues such as substance misuse and serious depressive symptoms are associated with these high rates. A youth's stay in these facilities is an opportune time to screen not only for sexual risk behaviours but also for mental health problems; appropriate risk reduction education and referrals can then be provided as needed.

Methicillin-resistant Staphylococcus aureus colonization among medical residents.

BACKGROUND: Medical residents may be at risk of becoming colonized by methicillin-resistant Staphylococcus aureus (MRSA) during their training. The occupational risk of this specific population is unknown. Furthermore, there are no data regarding MRSA colonization among health care professionals in Quebec. OBJECTIVE: To determine the MRSA colonization rate in Laval University (Quebec City, Quebec) medical residents and compare it with the MRSA colonization rate of a control group. METHODS: A controlled cross-sectional study of MRSA prevalence among medical residents of Laval University was performed. The control group consisted of Laval University undergraduate medical students without previous clinical rotations in their curriculum. After informed consent was obtained, participants were screened for MRSA with a nasal swab in both anterior nares. They also completed a questionnaire regarding relevant risk factors and demographic data. RESULTS: A total of 250 residents of all residency levels from medical and surgical specialties and 247 controls were recruited between February and April 2010. One case of MRSA colonization was detected among the residents and none in the control group (prevalence of 0.4% versus 0.0%; P=1.00). DISCUSSION: MRSA nasal carriage was very low among Laval University residents. This may reflect the decreasing rate of health care-associated MRSA in Quebec City. Young age and good health may also explain this low risk. The strict infection control policies for MRSA patients (including cohorting, use of gloves, gown and patient-dedicated equipment) may also contribute to prevent MRSA transmission. CONCLUSIONS: Medical residents in Quebec City appeared to be at very low risk of contracting MRSA through professional activities.

HISTORIQUE: Les résidents en médecine peuvent être à risque d'être colonisés par le Staphylococcus aureus résistant à la méthicilline (SARM) pendant leur formation. On ne connaît pas le risque professionnel de cette population. De plus, il n'existe pas de données sur la colonisation par le SARM des professionnels de la santé au Québec. OBJECTIF: Déterminer le taux de colonisation par le SARM des résidents en médecine de l'Université Laval (de Québec, au Québec) et le comparer à celui d'un groupe témoin. MÉTHODOLOGIE: Les chercheurs ont mené une étude transversale contrôlée de la prévalence du SARM chez les résidents en médecine de l'Université Laval. Le groupe témoin se composait d'étudiants en médecine non spécialisés de l'Université Laval qui n'avaient pas encore fait de rotations cliniques dans leur cursus. Après avoir donné leur consentement éclairé, les participants ont subi un test de dépistage du SARM au moyen d'un prélèvement dans les deux narines. Ils ont également rempli un questionnaire au sujet des facteurs de risque pertinents et des données démographiques. RÉSULTATS: Au total, les chercheurs ont recruté 250 résidents de toutes les années de résidence en spécialité de la médecine et de la chirurgie et 247 sujets témoins entre février et avril 2010. Ils ont dépisté un cas de colonisation par le SARM chez les résidents et n'en ont trouvé aucun dans le groupe témoin (prévalence de 0,4 % par rapport à 0,0 %; P=1,00). EXPOSÉ: Le portage nasal du SARM était très faible chez les résidents de l'Université Laval. Ce constat peut refléter le taux décroissant de SARM associés aux soins de santé dans la ville de Québec. Un jeune âge et une bonne santé peuvent également expliquer ce faible risque. Les politiques de contrôle des infections rigoureuses liées aux patients ayant un SARM (y compris le regroupement en cohortes, le port des gants et l'utilisation d'une blouse et de matériel réservés au patient) peuvent également contribuer à prévenir la transmission du SARM. CONCLUSIONS: Les résidents en médecine de la ville de Québec semblaient très peu à risque de contracter un SARM à cause de leurs activités professionnelles.

Healthcare-associated bloodstream infections secondary to a urinary focus: the Québec provincial surveillance results.

OBJECTIVE: Urinary tract infections (UTIs) are an important source of secondary healthcare-associated bloodstream infections (BSIs), where a potential for prevention exists. This study describes the epidemiology of BSIs secondary to a urinary source (U-BSIs) in the province of Québec and predictors of mortality. DESIGN: Dynamic cohort of 9,377,830 patient-days followed through a provincial voluntary surveillance program targeting all episodes of healthcare-associated BSIs occurring in acute care hospitals. SETTING: Sixty-one hospitals in Québec, followed between April 1, 2007, and March 31, 2010. PARTICIPANTS: Patients admitted to participating hospitals for 48 hours or longer. METHODS: Descriptive statistics were used to summarize characteristics of U-BSIs and microorganisms involved. Wilcoxon and χ(2) tests were used to compare U-BSI episodes with other BSIs. Negative binomial regression was used to identify hospital characteristics associated with higher rates. We explored determinants of mortality using logistic regression. RESULTS: Of the 7,217 reported BSIs, 1,510 were U-BSIs (21%), with an annual rate of 1.4 U-BSIs per 10,000 patient-days. A urinary device was used in 71% of U-BSI episodes. Identified institutional risk factors were average length of stay, teaching status, and hospital size. Increasing hospital size was influential only in nonteaching hospitals. Age, nonhematogenous neoplasia, Staphylococcus aureus, and Foley catheters were associated with mortality at 30 days. CONCLUSION: U-BSI characteristics suggest that urinary catheters may remain in patients for ease of care or because practitioners forget to remove them. Ongoing surveillance will enable hospitals to monitor trends in U-BSIs and impacts of process surveillance that will be implemented shortly.

Diabetes and the severity of pandemic influenza A (H1N1) infection.

OBJECTIVE: To confirm the existence of an increased risk of complications from influenza A (H1N1)p among patients with diabetes. RESEARCH DESIGN AND METHODS: Using data from an enhanced influenza surveillance project in Montreal, Canada, and age/sex-specific population estimates of diabetes prevalence, we estimated the risk of hospitalization among persons with diabetes. Comparing hospitalized patients admitted or not to an intensive care unit (ICU), we estimated the risk of ICU admission associated with diabetes, controlling for other patient characteristics. RESULTS: Among 239 hospitalized patients with PCR-confirmed influenza A (H1N1)p, 162 (68%) were interviewed, of whom 22 had diabetes, when 7.1 were expected (prevalence ratio 3.10 [95% CI 2.04-4.71]). The odds ratio for ICU admission was 4.29 (95% CI 1.29-14.3) among hospitalized patients with diabetes compared to those without. CONCLUSIONS: Diabetes triples the risk of hospitalization after influenza A (H1N1)p and quadruples the risk of ICU admission once hospitalized.

Behavioural risks for HIV infection among Quebec residents of Haitian origin.

Quebecers of Haitian origin (QHO) have the highest HIV prevalence of all immigrant groups in the province. We conducted a study among QHO to document the behavioural risk factors for HIV transmission. Male respondents were significantly more likely than female respondents to have at least one casual heterosexual partner in the past 12 months (39.7 vs. 18.8%, p < 0.001). Males were more likely to have used a condom at last sexual intercourse with a casual partner (78.9 vs. 53.7%; p = 0.002). However, among men who never, casually, or rarely used condoms with their regular female partner, 27.3% did not use a condom at last sexual intercourse with a casual partner. In the multivariable logistic regression analysis, having at least one casual heterosexual partner in the past 12 months was associated with being younger than 29 years, being male, being single, and being a second-generation QHO. This study allows us to identify subgroups whose behaviours can result in greater vulnerability to HIV infection and other STIs.

Assessment of exposure to pyrethroids and pyrethrins in a rural population of the Montérégie area, Quebec, Canada.

Pesticide use remains a preoccupation of the population and public health authorities given its possible impact on health. Pyrethroids can be listed among the widely used pesticides. The general population is potentially chronically exposed to pyrethroids mainly through food intake, but acute or sporadic exposures can also occur by other routes. Although pyrethroids are considered among the least toxic pesticides, their neurotoxic properties can affect humans, but current exposure levels in the population of Quebec are not known. The study thus aimed at assessing pyrethroid exposure in a rural, agricultural population during summer through measurements of urinary biomarkers. A total of 163 volunteers, 49 children and 114 adults, living in the Montérégie area of Quebec, participated in the study, which took place from June to August 2006, the period of intensive application of pesticides. Participants were asked to collect all their micturitions from 6 p.m. until the next morning, including first morning void, and to fill out a questionnaire to document factors that could potentially contribute to exposure. A gas-chromatography mass-spectrometry method was used to quantify six urinary metabolites resulting from pyrethroid biotransformation: cis- and trans-2,2-(dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (cDCCA and tDCCA), 3-phenoxybenzoic acid (PBA), chrysanthemum dicarboxylic acid (CDCA), cis-2,2-(dibromovinyl)-2,2-dimethylcyclopropane carboxylic acid (DBCA) and 4-fluoro-3-phenoxybenzoic acid (FPBA). Distributions of amounts of the six metabolites excreted per unit of body weight, during a standardized 12-hr period, followed the same decreasing pattern in adults and in children: tDCCA > PBA > cDCCA > CDCA > DBCA > FPBA. No statistically significant difference was observed between the two groups, but amounts of metabolites varied greatly among individuals, suggesting important interindividual variations in the absorbed doses of these compounds. No consistent associations were observed between the excretion of correlated metabolites and the various factors documented by questionnaire (personal factors, life habits, sources of exposure). Comparison of the current data with those observed in an urban population of the same province during the summer of 2005 suggests a greater summertime exposure to some pyrethroids in the rural population.

Access to sterile injecting equipment is more important than awareness of HCV status for injection risk behaviors among drug users.

Awareness of hepatitis C virus (HCV) infection status is expected to influence risk behaviors. In 2004-2005, injection drug users (IDUs) recruited from syringe exchange programs (SEPs) and methadone clinics in Montreal, Canada, were interviewed on drug use behaviors (past 6 months) and HCV testing. Subjects (n = 230) were classified as low/intermediate risk (20.4% borrowed drug preparation equipment only) and high risk (19.6% borrowed syringes), and 54.5% reported being HCV positive. Logistic regression modeling showed that compared to no risk (60% borrowed nothing), low/intermediate risk was associated with fewer noninjecting social network members, poor physical health, and problems obtaining sterile injecting equipment. High risk was associated with all of these factors except social networks. HCV status was not associated with any level of risk. Improved access to sterile injecting equipment may be more important than knowledge of HCV status in reducing injection risks among this IDU population. The study limitations are noted and recommendations discussed.

Repeated measures of validated and novel biomarkers of exposure to polycyclic aromatic hydrocarbons in individuals living near an aluminum plant in Quebec, Canada.

A longitudinal biomonitoring study was conducted to assess exposure to polycyclic aromatic hydrocarbons (PAH) in non-occupationally exposed nonsmoking adults living in the vicinity of an aluminum plant. Metabolites of several PAH (pyrene, naphthalene, chrysene, fluoranthene, benz[a]anthracene) were measured in the urine of the participants, including 1-hydroxypyrene (1-OHP) as a validated biomarker and pyrene diones as novel biomarkers. In total, 73 individuals living about 1 km away from the plant (taken as the exposed group) were compared repeatedly with 71 individuals living at least 11 km from the smelter (used as the control group). Complete first morning voids were collected twice, at a 2-wk interval, in the fall of 2005 and twice weekly for 2 consecutive weeks in the spring of 2006. Urinary biomarker concentrations were then measured by an ultra-performance liquid chromatography (UPLC) method with time-of-flight mass spectrometry detection (MS-TOF) (UPLC-MS-TOF). For most sampling days, individuals living near the plant showed significantly higher excretion values of both 1-OHP and pyrene diones (mean ratio up to 2- and 2.4-fold, respectively) than individuals living further from the plant. In the group living near the plant, geometric mean concentrations of 1-OHP varied from 0.047 to 0.058 micromol/mol creatinine, depending on the sampling day, as compared to 0.025 to 0.04 micromol/mol creatinine in the reference group. Corresponding mean values for pyrene diones were 0.017-0.056 micromol/mol creatinine and 0.014-0.039 micromol/mol creatinine, respectively. Urinary 1- and 2-naphthols were also measured as a reference and showed no significant differences between the two groups for most sampling days; metabolite concentrations of the other monitored PAH (chrysene, fluoranthene, benz[a]anthracene) were mostly below the analytical limit of detection of 0.005 to 0.01 microg/L, depending on the metabolite, with a detection rate varying from 0 to at most 21%. Individuals living near the aluminum plant thus appeared to be repeatedly exposed to higher pyrene levels than the control group, on the basis of both 1-OHP and pyrene dione excretions. However, 1-OHP concentrations observed in this first group were similar to those of other reference populations of nonsmokers studied in the past. Uptake of the other PAH associated with plant emissions was too small to significantly increase the excretion of their metabolites.

Low perceived benefits and self-efficacy are associated with hepatitis C virus (HCV) infection-related risk among injection drug users.

Hepatitis C prevention counselling and education are intended to increase knowledge of disease, clarify perceptions about vulnerability to infection, and increase personal capacity for undertaking safer behaviours. This study examined the association of drug equipment sharing with psychosocial constructs of the AIDS Risk Reduction Model, specifically, knowledge and perceptions related to hepatitis C virus (HCV) among injection drug users (IDUs). Active IDUs were recruited between April 2004 and January 2005 from syringe exchange and methadone maintenance treatment programs in Montreal, Canada. A structured, interviewer-administered questionnaire elicited information on drug preparation and injection practices, self-reported hepatitis C testing and infection status, and AIDS Risk Reduction Model constructs. Separate logistic regression models were developed to examine variables in relation to: (1) the sharing of syringes, and (2) the sharing of drug preparation equipment (drug containers, filters, and water). Among the 321 participants, the mean age was 33 years, 70% were male, 80% were single, and 91% self-identified as Caucasian. In the multivariable analyses, psychosocial factors linked to syringe sharing were lower perceived benefits of safer injecting and greater difficulty to inject safely. As with syringe sharing, the sharing of drug preparation equipment was associated with lower perceived benefits of safer injecting but also with low self-efficacy to convince others to inject more safely. Interventions should aim to heighten awareness of the benefits of risk reduction and provide IDUs with the skills necessary to negotiate safer injecting with their peers.

Minimal uptake of sterile drug preparation equipment in a predominantly cocaine injecting population: implications for HIV and hepatitis C prevention.

OBJECTIVE: To identify factors associated with using sterile drug injection equipment by injection drug users (IDUs). METHODS: 275 IDUs were recruited from syringe exchange programs in Montreal, Canada in 2004-2005. A structured, interviewer-administered questionnaire collected information about demographics, drug injection practices, self-reported HIV and hepatitis C virus (HCV) status, and harm reduction behaviours. Logistic regression was used to model variables in relation to the use of sterile syringes, containers, filters, and drug preparation water. RESULTS: Sterile syringes, containers, filters, and water were used for at least half of injecting episodes by 95%, 23%, 23%, and 75% of subjects, respectively. In multivariate analysis, users of sterile syringes had higher odds of being older and injecting alone, and were less likely to report problems obtaining sterile syringes and requiring or providing help with injecting. Using sterile filters was associated with having at least high school education, injecting heroin, and injecting alone. In addition to the factors associated with filters, users of sterile containers were more likely to be HCV-negative and older. Using sterile water was associated with daily injecting and being HCV-negative. CONCLUSIONS: Improving the uptake of sterile drug preparation equipment among IDUs could be aided by considering drug-specific risks, such as drug of choice and injecting context, while reinforcing existing messages on safer injecting. The association between sterile equipment use and HCV-negative status may be representative of an established subgroup of safer injectors who have remained free of infection because of consistent safe injecting practices.

Biological monitoring of exposure to organophosphate pesticides in children living in peri-urban areas of the Province of Quebec, Canada.

OBJECTIVE: This study was undertaken to assess the exposure to organophosphate (OP) pesticides in children from peri-urban areas of the Province of Quebec, Canada, through measurements of semi-specific alkylphosphate (AP) metabolites. METHODS: Eighty-nine children aged between 3 and 7 years were recruited via pamphlets sent to day-care centers. A first morning urine void was collected early in the spring of 2003 prior to summertime, which is the usual period of outdoor pesticide use. During summertime, up to five more first morning voids were repeatedly collected, at 72-h intervals, over a 13-day period. The potential determinants of exposure were assessed by a questionnaire at the time of urine collection. RESULTS: Methylphosphate metabolites were detectable in 98.2% of the 442 samples analyzed while ethylphosphates were detected in 86.7% of the samples. The geometric mean concentration (GM) of the total AP metabolites was 61.7 mug/g creatinine (range: 2.7-1967.3 mug/g creatinine). The difference in urinary AP concentrations between samples collected during spring and summer was non-significant (P=0.08). There was also no significant difference in the mean AP concentrations between summer samples of individuals living in municipalities where outdoor pesticide use is or is not restricted (P=0.25). However, the presence of a pet in the house was associated with an increase in AP concentrations during spraying season (P=0.02). Pesticides were seldom used, as reported by the questionnaire. A significant correlation was also observed (P<0.001) between the urinary AP concentrations in samples provided by siblings at the same time period. CONCLUSIONS: Mean concentrations of AP were generally higher than those reported in other studies. The observed exposure apparently occurred mainly through the dietary ingestion of OP residues. These data raise questions on the levels of OP residues in Quebec food and the possibility that our participants consumed more fruits and vegetables than those in other studies.