Transmission dynamics of SARS-CoV-2 in British Columbia's largest school district during the second half of the 2020-2021 school year.

OBJECTIVES: To determine the extent and characteristics of in-school transmission of SARS-CoV-2 and determine risk factors for in-school acquisition of COVID-19 in one of Canada's largest school districts. METHODS: We conducted a retrospective chart review of all reportable cases of COVID-19 who attended a kindergarten-Grade 12 (K-12) school within the study area between January and June of the 2020-2021 school year. The acquisition source was inferred based on epidemiological data and, when available, whole genome sequencing results. Mixed effects logistic regression was performed to identify risk factors independently associated with in-school acquisition of COVID-19. RESULTS: Overall, 2877 cases of COVID-19 among staff and students were included in the analysis; of those, 9.1% had evidence of in-school acquisition. The median cluster size was two cases (interquartile range: 1). Risk factors for in-school acquisition included being male (adjusted odds ratio [aOR]: 1.59, 95% confidence interval [CI]: 1.17-2.17), being a staff member (aOR: 2.62, 95% CI: 1.64-4.21) and attending or working in an independent school (aOR: 2.28, 95% CI: 1.13-4.62). CONCLUSION: In-school acquisition of COVID-19 was uncommon during the study period. Risk factors were identified in order to support the implementation of mitigation strategies that can reduce transmission further.

RéSUMé: OBJECTIFS: Déterminer l'étendue et les caractéristiques de la transmission de la SRAS-CoV-2 en milieu scolaire, et déterminer les facteurs de risque de l'acquisition de la COVID-19 dans l'un des plus larges arrondissements scolaires du Canada. MéTHODES: Nous avons mené un examen rétrospectif des dossiers de tous les cas signalés de COVID-19 ayant fréquenté une école de niveau élémentaire, primaire ou secondaire dans la zone à l'étude entre janvier et juin de l'année scolaire 2020-2021. La source d'acquisition était inférée sur la base des données épidémiologiques et, lorsque disponibles, les résultats de séquençage du génome entier. Nous avons eu recours à des régressions logistiques multiniveaux pour identifier les facteurs indépendamment associés avec l'acquisition de la COVID-19 en milieu scolaire. RéSULTATS: Au total, 2 877 cas de COVID-19 parmi les employés et les élèves ont été inclus dans l'analyse; de ceux-ci, 9,1 % avaient acquis l'infection en milieu scolaire. La grosseur médiane des agrégats était de deux cas (écart interquartile : 1). Les risques facteurs de l'acquisition en milieu scolaire incluaient le fait d'être de sexe masculin (rapport de cotes ajusté [RCa] : 1,59, intervalle de confiance [IC] de 95% : 1,17-2,17), être un membre du personnel (RCa : 2,62, IC de 95% : 1,64-4,21) et fréquenter ou travailler dans une école indépendante (RCa : 2,28, IC de 95% : 1,13-4,62). CONCLUSION: Nos résultats suggèrent que l'acquisition de la COVID-19 en milieu scolaire était peu commune pendant la période d'étude. Des facteurs de risque ont été identifiés afin de supporter l'implémentation de mesures de contrôle pouvant réduire davantage la transmission.

Duration of influenza outbreaks in long-term care facilities after antiviral prophylaxis initiation: Fraser Health, British Columbia, 2014-2017.

To assess the duration of antiviral prophylaxis (AP), we conducted a retrospective outbreak review over 3 seasons, looking for acute respiratory illness (ARI) onset after 5 days of AP. Of 114 facility-level outbreaks with 352 unit-level outbreaks, we found only 1 case of laboratory-confirmed influenza after 5 days of AP. New cases of ARI after 5 days of AP should be investigated, and recommendations for AP duration could be shortened to 7-8 days or less.

Estimated protective effectiveness of intramuscular immune serum globulin post-exposure prophylaxis during a measles outbreak in British Columbia, Canada, 2014.

INTRODUCTION: Intramuscular Immune Serum Globulin (IM ISG) is recommended as post-measles exposure prophylaxis (PEP) when administered within 6days of initial exposure, with variable effectiveness in preventing measles disease. Effectiveness of IM ISG PEP in preventing clinical measles was assessed during a 2014 measles outbreak among a religious-affiliated community in British Columbia, Canada. MATERIAL AND METHODS: Fifty-five self-reporting measles susceptible contacts were offered exclusively IM ISG PEP within an eligibility period best surmised to be within 6days of initial measles case exposure. Clinical outcome of IM ISG PEP recipients was determined by selective active surveillance and case self-reporting. IM ISG PEP failure was defined as onset of a measles-like rash 8-21days post-IM ISG PEP. Post-IM ISG PEP measles IgG antibody level was tested in 8 recipients. Factors associated with measles disease were analyzed. RESULTS: Seventeen of 55 IM ISG PEP recipients developed clinically consistent measles in the following 8-21days, corresponding to an estimated crude protective effectiveness of 69%. In school aged children 5-18years, among whom potential exposure intensity and immune status confounders were considered less likely, estimated IM ISG PEP protective effectiveness was 50%. Age <25years was significantly associated with breakthrough clinical measles in bivariate analysis (p=0.0217). Among 8 tested contacts of 17 considered IM ISG PEP failures, post-IM ISG PEP measles IgG antibody levels (mean 16.3days (range 16-17days) post-PEP) were all <150mIU/ml. CONCLUSIONS: The estimated crude IM ISG PEP protective effectiveness against measles disease within 8-21days post-ISG administration was 69%. Accuracy of this estimated protective effectiveness is vulnerable to assumptions and uncertainties in ascertaining exposure details and pre-exposure immune status. Increasing the Canadian recommended measles IM ISG PEP dose from 0.25 to 0.5ml/kg (up to 15ml maximum volume) may increase protective effectiveness.

Reliability and validity of the Daily Cognitive-Communication and Sleep Profile: a new instrument for monitoring sleep, wakefulness and daytime function.

The Daily Cognitive Communicative and Sleep Profile (DCCASP) is a seven-item instrument that captures daily subjective sleep quality, perceived mood, cognitive, and communication functions. The objective of this study was to evaluate the reliability and validity of the DCCASP. The DCCASP was self-administered daily to a convenience sample of young adults (n = 54) for two two-week blocks, interspersed with a two-week rest period. Afterwards, participants completed the Pittsburgh Sleep Quality Index (PSQI). Internal consistency and criterion validity were calculated by Cronbach's α coefficient, Concordance Correlation Coefficient (CCC), and Spearman rank (rs) correlation coefficient, respectively. Results indicated high internal consistency (Cronbach-s α = 0.864-0.938) among mean ratings of sleep quality on the DCCASP. There were significant correlations between mean ratings of sleep quality and all domains (rs=0.38-0.55, p<0.0001). Criterion validity was established between mean sleep quality ratings on the DCCASP and PSQI (rs=0.40, p<0.001). The DCCASP is a reliable and valid self-report instrument to monitor daily sleep quality and perceived mood, cognitive, and communication functions over time, amongst a normative sample of young adults. Further studies on its psychometric properties are necessary to clarify its utility in a clinical population.

Bevacizumab for advanced breast cancer: hope, hype, and hundreds of headlines.

On February 22, 2008, the Food and Drug Administration granted accelerated approval for the use of bevacizumab (Avastin) in metastatic breast cancer. Based on subsequent clinical trials, this approval was revoked on November 18, 2011. In this study, we categorize and analyze the newspaper reports related to bevacizumab's use in advanced breast cancer. Methods. Using the Factiva media database, we reviewed all newspaper reports published in North America from January 4, 2002, to January 4, 2013, containing the words "breast cancer" and "Avastin," or "bevacizumab." Articles were classified as pre-approval (January 4, 2002-February 21, 2008), approval (February 22, 2008-November 17, 2011), or post-approval loss (November 18, 2011-January 4, 2013). Information regarding benefits, side effects, costs, interviewees, and article tone and theme were abstracted from each article by two independent reviewers. Differences among the three study phases were compared using the chi square analysis. Results. A total of 359 articles met study inclusion criteria. The number of reports having a positive headline tone and/or positive article tone declined with each study period. The proportion of articles discussing side effects and financial costs increased, whereas those discussing efficacy decreased with each study period. Drug representatives were most likely to be quoted in newspaper articles prior to bevacizumab's approval. Conclusion. Media reports are a common source of medical information for patients, practitioners, and policy makers. We observed substantial fluidity of media reports over time.

The impact of a population-level school food and nutrition policy on dietary intake and body weights of Canadian children.

OBJECTIVE: The objective of this study is to assess population-level trends in children's dietary intake and weight status before and after the implementation of a provincial school nutrition policy in the province of Nova Scotia, Canada. METHOD: Self-reported dietary behavior and nutrient intake and measured body mass index were collected as part of a population-level study with grade 5 students in 2003 (n=5215) and 2011 (5508), prior to and following implementation of the policy. We applied random effects regression methods to assess the effect of the policy on dietary and health outcomes. RESULTS: In 2011, students reported consuming more milk products, while there was no difference in mean consumption of vegetables and fruits in adjusted models. Adjusted regression analysis revealed a statistically significant decrease in sugar-sweetened beverage consumption. Despite significant temporal decreases in dietary energy intake and increases in diet quality, prevalence rates of overweight and obesity continued to increase. CONCLUSION: This population-level intervention research suggests a positive influence of school nutrition policies on diet quality, energy intake and healthy beverage consumption, and that more action beyond schools is needed to curb the increases in the prevalence of childhood obesity.

Fruit and vegetable preferences and intake among children in Alberta.

PURPOSE: The association between preference for and intake of fruits and vegetables was examined among Albertan children. METHODS: Data used were collected as part of a provincial population-based survey among grade 5 children in Alberta. Intake of two fruits and five vegetables was assessed using the Harvard food frequency questionnaire, and preference for individual fruit and vegetable items was rated using a three-point Likert-type scale. Random effects models with children nested within schools were used to test for associations between fruit and vegetable preference and intake. RESULTS: A total of 3398 children aged 10 to 11 years returned completed surveys. Children who reported a greater liking for fruits and vegetables also reported significantly (p<0.001) higher intake. On average, children who liked a food a lot ate 0.5 to 2.7 more weekly servings of the food than did children who did not like the food. CONCLUSIONS: These findings suggest that focusing on interventions designed to increase taste preference may lead to increased fruit and vegetable intake among children. Introducing children to unfamiliar fruits and vegetables through taste testing may be an effective and practical health promotion approach for improving dietary habits.

Cardiovascular risk-factor profiles of normal and overweight children and adolescents: insights from the Canadian Health Measures Survey.

BACKGROUND: There is no cardiovascular disease (CVD) risk factor profile in a representative sample of Canadian children and adolescents according to weight status. The 2007-2009 Canadian Health Measures Survey, launched by Statistics Canada in partnership with Health Canada and the Public Health Agency of Canada, provides an opportunity to address this gap. METHODS: The Canadian Health Measures Survey collected information at 15 sites across Canada from March 2007 to March 2009 from Canadians aged 6 to 79 years living in private households. The survey consisted of a household interview and a visit to a mobile examination centre to perform physical measurements, including anthropometry, blood pressure, and biospecimen collection. The present analysis is based on data from 2087 children and adolescents aged 6 to 19 years. RESULTS: Children and adolescents who were overweight or obese had on average higher mean concentrations and higher prevalence of adverse levels of CVD risk factors (systolic and diastolic blood pressure, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoprotein B, C-reactive protein, homocysteine, and insulin levels) than did normal-weight children and adolescents. Adjustment for covariates (gender, age, household education, household income adequacy, and province of residence) and compliance with recommendations for daily steps, soft-drink intake, and sleep duration did not alter the differences in CVD risk factors between normal weight and overweight or obese children and adolescents. CONCLUSIONS: Results of this study underscore the importance of excess weight as an independent risk factor for CVD health in early life and call for primary prevention of overweight and obesity in childhood to reduce CVD risk.

Involvement in home meal preparation is associated with food preference and self-efficacy among Canadian children.

OBJECTIVE: To examine the association between frequency of assisting with home meal preparation and fruit and vegetable preference and self-efficacy for making healthier food choices among grade 5 children in Alberta, Canada. DESIGN: A cross-sectional survey design was used. Children were asked how often they helped prepare food at home and rated their preference for twelve fruits and vegetables on a 3-point Likert-type scale. Self-efficacy was measured with six items on a 4-point Likert-type scale asking children their level of confidence in selecting and eating healthy foods at home and at school. SETTING: Schools (n =151) located in Alberta, Canada. SUBJECTS: Grade 5 students (n = 3398). RESULTS: A large majority (83-93 %) of the study children reported helping in home meal preparation at least once monthly. Higher frequency of helping prepare and cook food at home was associated with higher fruit and vegetable preference and with higher self-efficacy for selecting and eating healthy foods. CONCLUSIONS: Encouraging children to be more involved in home meal preparation could be an effective health promotion strategy. These findings suggest that the incorporation of activities teaching children how to prepare simple and healthy meals in health promotion programmes could potentially lead to improvement in dietary habits.

Medication use in normal weight and overweight children in a nationally representative sample of Canadian children.

BACKGROUND: As overweight and obese children are more likely to develop serious medical conditions, they incur higher doctor and hospital costs compared to their normal weight counterparts. Consequently, the differential healthcare costs between obese and normal weight children may be even greater if medication use is considered. OBJECTIVE: To compare medication use between normal weight and overweight children in a nationally representative sample from Canada. METHODS: Data from the Canadian Health Measures Survey 2007/2009, a cross-sectional survey assessing indicators of health and wellness in Canadians, was used in the current study. The analysis included 2087 children and adolescents between 6-19 years of age with valid measures of body mass index (BMI). Poisson/negative binomial regression was used to examine the association between weight status and the number of medications taken in the last month. RESULT: For 6-11 year olds, the frequency of prescription, over-the-counter and natural health product (NHP) medication use did not differ between normal weight and overweight/obese children. For 12-19 year olds, overweight/obese children used prescription medication significantly more often than their normal weight peers (adjusted incidence rate ratio (IRR), 1.59; 95% CI 1.19 to 2.14), whereas for NHP the opposite was the case (adjusted IRR, 0.52; 95% CI 0.32 to 0.82). These children also used nervous system and respiratory medications more frequently than their normal weight peers. CONCLUSION: The findings of the present study suggest that the differential usage of prescription drugs among overweight/obese children underline the need to develop effective obesity prevention programmes and policies that may reduce the health and economic burden of childhood obesity.

From "best practice" to "next practice": the effectiveness of school-based health promotion in improving healthy eating and physical activity and preventing childhood obesity.

BACKGROUND: In 2005, we reported on the success of Comprehensive School Health (CSH) in improving diets, activity levels, and body weights. The successful program was recognized as a "best practice" and has inspired the development of the Alberta Project Promoting active Living and healthy Eating (APPLE) Schools. The project includes 10 schools, most of which are located in socioeconomically disadvantaged areas. The present study examines the effectiveness of a CSH program adopted from a "best practice" example in another setting by evaluating temporal changes in diets, activity levels and body weight. METHODS: In 2008 and 2010, we surveyed grade 5 students from approximately 150 randomly selected schools from the Canadian province of Alberta and students from 10 APPLE Schools. Students completed the Harvard Youth/Adolescent Food Frequency Questionnaire, questions on physical activity, and had their height and weight measured. Multilevel regression methods were used to analyze changes in diets, activity levels, and body weight between 2008 and 2010. RESULTS: In 2010 relative to 2008, students attending APPLE Schools were eating more fruits and vegetables, consuming fewer calories, were more physically active and were less likely obese. These changes contrasted changes observed among students elsewhere in the province. CONCLUSIONS: These findings provide evidence on the effectiveness of CSH in improving health behaviors. They show that an example of "best practice" may lead to success in another setting. Herewith the study provides the evidence that investments for broader program implementation based on "best practice" are justified.

Quantification of viable but nonculturable Escherichia coli O157:H7 by targeting the rpoS mRNA.

Escherichia coli O157:H7 easily becomes viable but nonculturable (VBNC) under environmental stresses and escapes detection by current methods. Here, we report a unique method enabling the quantification of VBNC E. coli O157:H7 using a selective marker within the rpoS gene. A nucleotide at position +543 within the rpoS gene open reading frame was identified to be unique to E. coli O157:H7. Specifically designed primers and probe combinations were able to differentiate E. coli O157:H7 from closely related bacteria and other common bacteria. The application of this strategy correctly identified 36 clinical and bovine isolates of E. coli O157:H7. A one-step quantification method combining reverse transcription (RT) and real-time quantitative polymerase chain reaction (qPCR) was developed to provide a linear relationship (R(2) > 0.99) of copies of RNA with threshold cycles (Ct) and the capability of detecting a single copy of rpoS RNA standards. This technique was used to determine the copies of the rpoS mRNA in culturable cells at different growth phases (mid-log, late-log, and stationary phase) to be 1.57, 0.56, and 0.41 copies/CFU, respectively. VBNC E. coli O157:H7 was determined to have one copy of the rpoS mRNA for every 10 cells, and no rpoS mRNA was detected in 10(6) dead cells and negative controls. This technique had a linear dynamic range over 6 orders of magnitude and >90% amplification efficiency for tap and river water samples. It was able to selectively quantify as few as 7 E. coli O157:H7 cells in pure culture, 9 culturable cells in tap water and river water, and 23 VBNC cells in river water, demonstrating the best quantification limits for culturable and VBNC E. coli O157:H7 in environmental water.