The use of multiple hypothesis-generating methods in an outbreak investigation of Escherichia coli O121 infections associated with wheat flour, Canada 2016-2017.

A Canadian outbreak investigation into a cluster of Escherichia coli O121 was initiated in late 2016. When initial interviews using a closed-ended hypothesis-generating questionnaire did not point to a common source, cases were centrally re-interviewed using an open-ended approach. The open-ended interviews led cases to describe exposures with greater specificity, as well as food preparation activities. Data collected supported hypothesis generation, particularly with respect to flour exposures. In March 2017, an open sample of Brand X flour from a case home, and a closed sample collected at retail of the same brand and production date, tested positive for the outbreak strain of E. coli O121. In total, 76% (16/21) of cases reported that they used or probably used Brand X flour or that it was used or probably was used in the home during their exposure period. Crucial hypothesis-generating techniques used during the course of the investigation included a centralised open-ended interviewing approach and product sampling from case homes. This was the first outbreak investigation in Canada to identify flour as the source of infection.

Outbreaks of Salmonella illness associated with frozen raw breaded chicken products in Canada, 2015-2019.

Frozen raw breaded chicken products (FRBCP) have been identified as a risk factor for Salmonella infection in Canada. In 2017, Canada implemented whole genome sequencing (WGS) for clinical and non-clinical Salmonella isolates, which increased understanding of the relatedness of Salmonella isolates, resulting in an increased number of Salmonella outbreak investigations. A total of 18 outbreaks and 584 laboratory-confirmed cases have been associated with FRBCP or chicken since 2017. The introduction of WGS provided the evidence needed to support a new requirement to control the risk of Salmonella in FRBCP produced for retail sale.

Comparison of 3-day and 7-day recall periods for food consumption reference values in foodborne disease outbreak investigations.

Investigations into an outbreak of foodborne disease attempt to identify the source of illness as quickly as possible. Population-based reference values for food consumption can assist in investigation by providing comparison data for hypothesis generation and also strengthening the evidence associated with a food product through hypothesis testing. In 2014-2015 a national phone survey was conducted in Canada to collect data on food consumption patterns using a 3- or 7-day recall period. The resulting food consumption values over the two recall periods were compared. The majority of food products did not show a significant difference in the consumption over 3 days and 7 days. However, comparison of reference values from the 3-day recall period to data from an investigation into a Salmonella Infantis outbreak was shown to support the conclusion that chicken was the source of the outbreak whereas the reference values from a 7-day recall did not support this finding. Reference values from multiple recall periods can assist in the hypothesis generation and hypothesis testing phase of foodborne outbreak investigations.

Estimated hospitalizations attributed to norovirus and rotavirus infection in Canada, 2006-2010.

Enteric viruses including norovirus and rotavirus are leading causes of gastroenteritis in Canada. However, only a small number of clinical cases are actually tested for these pathogens leading to systematic underestimation of attributed hospitalizations in administrative databases. The objective of this analysis was to estimate the number of hospitalizations due to norovirus and rotavirus in Canada. Hospitalization records for acute gastroenteritis-associated discharges at all acute-care hospitals in Canada between 2006 and 2011 were analysed. Cause-unspecified gastroenteritis hospitalizations were modelled using age-specific negative binomial models with cause-specified gastroenteritis admissions as predictors. The coefficients from the models were used to estimate the number of norovirus and rotavirus admissions. The total annual hospitalizations for rotavirus were estimated to be between 4500 and 10 000. Total annual hospitalizations for norovirus were estimated to be between 4000 and 11 000. The mean total annual cost associated with these hospitalizations was estimated to be at least $16 million for rotavirus and $21 million for norovirus (all figures in Canadian dollars). This study is the first comprehensive analysis of norovirus and rotavirus hospitalizations in Canada. These estimates provide a more complete assessment of the burden and economic costs of these pathogens to the Canadian healthcare system.

Comparison of visual and computerised antenatal cardiotocography in the prevention of perinatal morbidity and mortality. A systematic review and meta-analysis.

INTRODUCTION: Antenatal cardiotocography (CTG) is used to monitor fetal well-being. There are two methods: visual (vCTG) or computerised (cCTG). An earlier Cochrane review compared the effects of both approaches on maternal and fetal outcomes. The objective of this systematic review was to update this search and identify studies not included in the Cochrane review. MATERIALS AND METHODS: MEDLINE, EMBASE, CINAHL and MIDIRS databases were searched up to February 2021. We included randomised controlled trials (RCT) and non-randomised studies (NRS) of pregnant women receiving antenatal CTG with comparison of cCTG to vCTG and clinical outcomes. The Cochrane Risk of Bias Tool and Joanna Briggs Institute Critical Appraisal Checklist were used for quality assessment. Data is presented as risk ratios with 95% confidence intervals and I2 is used as the statistical measure of heterogeneity. RESULTS: Three RCTs and three NRS were included. Meta-analysis of RCTs demonstrated a non-significant reduction in all-cause perinatal mortality (RR 0.23 [95%CI 0.04-1.30]), preventable perinatal mortality excluding congenital anomalies (RR 0.27 [95% CI 0.05-1.56]) and cesarean section (RR 0.91 [95%CI 0.68-1.22]). All RCTs included high-risk women and had a high risk of bias. There was one antenatal stillbirth across the three RCTs (n = 497). The NRS were at high-risk of bias and statistical analysis was not possible due to heterogeneity. Individual findings suggest reduced investigation and better prediction of neonatal outcomes with cCTG. CONCLUSIONS: There is a non-significant reduction in perinatal mortality with cCTG. Despite no clear reduction in perinatal mortality and morbidity with cCTG, it is objective and may reduce time spent in hospital and further investigations for women.

The occurrence of Campylobacter in river water and waterfowl within a watershed in southern Ontario, Canada.

AIMS: Quantitative PCR and a culture method were used to investigate Campylobacter occurrence over 3 years in a watershed located in southern Ontario, Canada that is used as a source of drinking water. METHODS AND RESULTS: Direct DNA extraction from river water followed by quantitative PCR analysis detected thermophilic campylobacters at low concentrations (<130 cells 100 ml(-1) ) in 57-79% of samples taken from five locations. By comparison, a culture-based method detected Campylobacter in 0-23% of samples. Water quality parameters such as total Escherichia coli were not highly correlated with Campylobacter levels, although higher pathogen concentrations were observed at colder water temperatures (<10°C). Strains isolated from river water were primarily nalidixic acid-susceptible Campylobacter lari, and selected isolates were identified as Campylobacter lari ssp. concheus. Campylobacter from wild birds (seagulls, ducks and geese) were detected at a similar rate using PCR (32%) and culture-based (29%) methods, and although Campylobacter jejuni was isolated most frequently, C. lari ssp. concheus was also detected. CONCLUSIONS: Campylobacter were frequently detected at low concentrations in the watershed. Higher prevalence rates using quantitative PCR was likely because of the formation of viable but nonculturable cells and low recovery of the culture method. In addition to animal and human waste, waterfowl can be an important contributor of Campylobacter in the environment. SIGNIFICANCE AND IMPACT OF THE STUDY: Results of this study show that Campylobacter in surface water can be an important vector for human disease transmission and that method selection is important in determining pathogen occurrence in a water environment.

Use of a case-control study and control bank to investigate an outbreak of locally acquired cyclosporiasis in Canada, 2016.

BACKGROUND: Cyclospora is an intestinal parasite that is not endemic in Canada. However, national outbreaks of locally acquired cases have been reported since 2013. These outbreaks were suspected to be associated with consumption of produce imported from countries where Cyclospora is endemic. Identification of the source can be challenging because of reporting delays and limited traceability of produce. OBJECTIVE: To report on a national outbreak of locally acquired cyclosporiasis, highlight the challenges of investigating these outbreaks and document the first time use of a control bank to recruit controls for a national outbreak case-control study in Canada. METHODS: Cases of cyclosporiasis were identified through provincial laboratory testing and reported through provinces to the national level. Cases were interviewed about food exposures using a questionnaire and food exposures reported by cases were compared to Foodbook reference values. To narrow down the food items of interest, a matched case-control study was conducted. Controls for the study were recruited primarily from a control bank, that is, a list of individuals who had previously agreed to participate in public health-related surveys. RESULTS: In total, 87 cases of locally acquired cyclosporiasis with onset or report dates between May 19, 2016 and August 10, 2016 were reported by four provinces. Comparing case exposures to Foodbook reference values identified several food items of interest, including blackberries, other berries, herbs and leafy greens. The case-control study identified only blackberries and mesclun greens as significantly more frequently consumed by cases than controls. Due to lack of product details for blackberries and mesclun greens, the source of the outbreak was not conclusively identified. CONCLUSION: Blackberries were the primary food item of interest, but could not be identified as the conclusive source due to lack of traceability. The control bank was found to be a useful tool for control recruitment.

Shoulder acute pain in primary healthcare: is retraining effective for GP principals? SAPPHIRE--a randomized controlled trial.

OBJECTIVE: To address the question whether general practitioners (GPs) should receive practical training in shoulder problems and to test whether cortisone injections are better than anaesthetic injections for rotator cuff problems. METHODS: A pragmatic split-plot, randomized trial with a cluster factorial design, conducted in general practices across five centres across the United Kingdom. Ninety-one practices were randomized to receive additional training in diagnosing and injecting rotator cuff problems or no additional training. Two hundred patients consulting their general practices with shoulder pain were then randomized to receive either a corticosteroid or lignocaine injection. The main outcome was score on the British Shoulder Disability Questionnaire (BSDQ). The Short-Form 36-item Health Survey and EuroQol at 12 months from entry to the trial were also scored. RESULTS: Over the course of the trial there was a mean difference of 0.94 (s.e. = 1.01) on the BSDQ score between the groups, with patients treated by the untrained group having a mean of 9.46 (s.e. = 0.82) and those by the trained group having a mean of 8.51 (s.e. = 0.60). There were no statistically significant differences between the groups. Analysing by substance injected, there was a mean difference of 0.15 (s.e. = 0.48) throughout the trial between the groups, with patients given the cortisone having a mean BSDQ of 9.67 (s.e. = 0.39) and those given lignocaine, 9.82 (s.e. = 0.39). This was not statistically significantly different. CONCLUSIONS: Training GPs in the diagnosis and treatment of shoulder disorders does not make any difference to the outcome, in terms of pain and disability, 1 yr later. Further, there is no advantage to injecting steroid in a group with predominant rotator cuff disorder. Trial registration. International Standard Randomized Controlled Trial Number 58537244. Trial steering committee comprised Prof. Paul Dieppe, Prof. Elaine Hay, Dr Brian Hazleman and Dr Kerenza Hood.

Chlorhexidine vaginal preparation versus standard treatment at caesarean section to reduce endometritis and prevent sepsis-a feasibility study protocol (the PREPS trial).

BACKGROUND: Worldwide caesarean section (CS) delivery is the most common major operation. Approximately 25% of pregnant women undergo a CS in the UK for delivery of their babies. Sepsis and post-natal infection constitute significant maternal mortality and morbidity. Infection following a CS has a number of primary sources including endometritis occurring in 7-17% of women. Sepsis reduction and reduction in antibiotic use have been identified as a national and international priority. The overarching aim of this research is to reduce infectious morbidity from caesarean sections. METHODS: This is a parallel group feasibility randomised controlled trial comparing vaginal cleansing using chlorhexidine gluconate versus no cleansing (standard practice) at CS to reduce infection. Women will be recruited from four National Health Service maternity units. Two hundred fifty women (125 in each arm) undergoing elective or emergency CS, who are aged 16 years and above, and at least 34 weeks pregnant will be randomised. Allocation to treatment will be on a 1:1 ratio. The study includes a qualitative aspect to develop women centred outcomes of wellbeing after delivery. DISCUSSION: The success of the feasibility study will be assessed by criteria related to the feasibility measurements to ascertain if a larger study is feasible in its current format, needs modification or is unfeasible, and includes recruitment, adherence, follow-up and withdrawal measures. TRIAL REGISTRATION: The PREPS trial has been registered with ISRCTN (ISRCTN 33435996).

An outbreak of Shiga toxin-producing Escherichia coli O121 infections associated with flour-Canada, 2016-2017†.

As of May 23, 2017, 29 cases of a new Escherichia coli O121 infection have been identified in six provinces (Alberta, British Columbia, Newfoundland and Labrador, Ontario, Quebec and Saskatchewan) linked with the consumption of uncooked flour. One additional case was identified in a U.S. resident who traveled to Canada during the exposure period. Patients' ages ranged from 2-79 years (median = 23.5 years) and 50% were female. Eight patients were hospitalized, and one developed hemolytic uremic syndrome. Because of the recent emergence of E. coli outbreaks linked to flour, public health professionals should consider flour as a possible source in E. coli outbreaks and communicate the risk associated with flour and raw batter/dough exposure in public health messaging.

Heavy metal concentrations in molluscs from the Senegal coast.

Bivalve molluscs from the Western coast of Senegal were sampled and measured for their cadmium, copper and zinc concentrations. This part of Africa has not been studied as regards heavy metal concentrations in the molluscs. The collected species are two small African bivalve molluscs, living in the sand: Cardita ajar and Dosinia isocardia; the African mussel Perna perna which is the only mussel of this genus in the Western coast of Africa and the oyster Crassostrea gasar, which lives in mangroves attached to the rhizophores, in the intertidal zone. C. gasar and C. ajar present higher cadmium concentrations, respectively 6.82+/-0.54 and 13.77+/-0.80 microg Cd/g (d.w.) than the two other species (D. isocardia: 3.88+/-0.31 microg/g and P. perna 2.37+/-0.22 microg/g. Copper and zinc concentrations are in the range of the published values for C. gasar and P. perna collected elsewhere in Africa. The results suggest that cadmium may be present in high concentrations in Senegalese waters where upwellings occur.

Associating Embedded Figures Test Performance with extreme hysteria and psychasthenia MMPI scores in a psychiatric population.

21 female subjects from a psychiatric population scoring high on one of two MMPI scales, Hysteria or Psychasthenia, were given Jackson's (1956) shortened version of the Embedded Figures Test. Hysteria correlates positively and significantly .71 with time spent in detecting embedded geometric figures. Obsessive-compulsiveness and Embedded Figures Test performance time are negatively correlated -.63. The average times were 102.5 sec. for hysteria subjects and 62.6 sec. for psychasthenia subjects. Chi-squared establishes the significant association of MMPI measurements for hysteria and obsessive-compulsiveness with field-dependence and field-independence, respectively.

The impact of impaired vocal quality on children's ability to process spoken language.

This paper investigated the effect of voice quality on children's ability to process spoken language. A group of 24 children, mean age 11 years 5 months, listened to a series of recorded short passages, half spoken by a female with normal voice and half spoken by a female with a classic vocal impairment (dysphonic voice). The children were tested for their ability to recall words and to draw a final target inference. Children performed better on both preceding indices when listening to the normal voice. The implications of the findings are discussed, with particular reference to the classroom situation.

Outbreak of E. coli O157:H7 associated with lettuce served at fast food chains in the Maritimes and Ontario, Canada, Dec 2012.

BACKGROUND: Identification and control of multi-jurisdictional foodborne illness outbreaks can be complex because of their multidisciplinary nature and the number of investigative partners involved. OBJECTIVE: To describe the multi-jurisdictional outbreak response to an E. coli O157:H7 outbreak in Canada that highlights the importance of early notification and collaboration and the value of centralized interviewing. METHODS: Investigators from local, provincial and federal jurisdictions, using a national outbreak response protocol to clarify roles and responsibilities and facilitate collaboration, conducted a rapid investigation that included centralized re-interview of cases, descriptive methods, binomial probability, and traceback findings to identify the source of the outbreak. RESULTS: There were 31 laboratory confirmed cases identified in New Brunswick, Nova Scotia, and Ontario. Thirteen cases (42%) were hospitalized and one case (3%) developed hemolytic uremic syndrome; there were no deaths. Due to early notification a coordinated investigation was initiated before laboratory subtyping was available. Re-interview of cases identified 10 cases who had not initially reported exposure to the source of the outbreak. Less than one week after the Outbreak Investigation Coordinating Committee was formed, consumption of shredded lettuce from a fast food chain was identified as the likely source of the illnesses and the implicated importer/processor initiated a precautionary recall the same day. CONCLUSION: This outbreak investigation highlights the importance of early notification, prompt re-interviewing and collaboration to rapidly identify the source of an outbreak.

Do baseline characteristics predict response to treatment for low back pain? Secondary analysis of the UK BEAM dataset [ISRCTN32683578].

OBJECTIVES: To identify characteristics of randomized controlled trial participants which predict greater benefits from physical treatments for low back pain. If successful, this would allow more appropriate selection of patients for different treatments. METHODS: We did a secondary analysis of the UK Back pain Exercise And Manipulation trial (UK BEAM n = 1334) dataset to identify baseline characteristics predicting response to manipulation, exercise and manipulation followed by exercise (combined treatment). Rather than simply identifying factors associated with overall outcome, we tested for the statistical significance of the interaction between treatment allocation, baseline characteristics and outcome to identify factors that predicted response to treatment. We also did a post-hoc subgroup analysis to present separate results for trial participants with subacute and chronic low back pain to inform future evidence synthesis. RESULTS: Age, work status, age of leaving school, 'pain and disability', 'quality of life' and 'beliefs' at baseline all predicted overall outcome. None of these predicted response to treatment. In those allocated to combined treatment, there was a suggestion that expecting treatment to be helpful might improve outcome at 1 yr. Episode length at study entry did not predict response to treatment. CONCLUSION: Baseline participant characteristics did not predict response to the UK BEAM treatment packages. Using recognized prognostic variables to select patients for different treatment packages, without first demonstrating that these factors affect response to treatment, may be inappropriate. In particular, this analysis suggests that the distinction between subacute and chronic low back pain may not be useful when considering treatment choices.

Setting standards for training and competence: the UK alcohol treatment trial.

AIMS: To examine factors that influence the recruitment and training of therapists and their achievement of competence to practise two psychological therapies for alcohol dependence, and the resources required to deliver this. METHODS: The protocol for the UK Alcohol Treatment Trial required trial therapists to be competent in one of the two trial treatments: Social Behaviour and Network Therapy (SBNT) or Motivational Enhancement Therapy (MET). Therapists were randomised to practise one or other type of therapy. To ensure standardisation and consistent delivery of treatment in the trial, the trial training centre trained and supervised all therapists. RESULTS: Of 76 therapists recruited and randomised, 72 commenced training and 52 achieved competence to practise in the trial. Length of prior experience did not predict completion of training. However, therapists with a university higher qualification, and medical practitioners compared to other professionals, were more likely to complete. The average number of clients needed to be treated before the trainee achieved competence was greater for MET than SBNT, and there was a longer duration of training for MET. CONCLUSIONS: Training therapists of differing professional backgrounds, randomised to provide a specific therapy type, is feasible. Supervision after initial training is important, and adds to the training costs.

Previously uncharacterized Mycoplasma isolates from an investigation of canine pneumonia.

Mycoplasmas recovered from the respiratory tract and genitourinary system of dogs, with and without respiratory infection, have been characterized by biological and immunological methods. Some of the isolates were indentified as being similar to the three species of canine mycoplasmas described earlier under the designation Mycoplasma spumans, M. canis, and M. maculosum. Other mycoplasmas placed in three groups (A, C, and D) were found to be clearly distinct from the three classified species. Group A strains fermented glucose but not mannose and were serologically distinct from other canine mycoplasmas recovered in this study. These strains were subsequently found to be biologically and serologically related to a previously reported, but unclassified, canine mycoplasma. Group D strains differed in some biological properties but were serologically related. These were found to be nonfermenting mycoplasmas representing isolations from the throat and bladder of dogs. They were serologically distinct from other canine mycoplasmas and were apparently unrelated to other known mycoplasma serotypes. Group C mycoplasmas were recovered only from the lungs of dogs. Within the group, they differ in some immunological properties but appear to be serologically distinct from other canine strains. They can also be separated from other dog strains in their ability to ferment glucose and mannose. Group B strains were found to have biological properties similar to M. canis strains but seemed to be only partially related to this serotype when examined in several serological techniques. It is suggested that these strains might represent antigenic variants of M. canis.