Outbreak of Salmonella Reading in persons of Eastern Mediterranean origin in Canada, 2014–2015
Bibliographic record
Abstract
Background: Salmonella Reading (S.Reading) is a rare serotype of Salmonella subspecies (spp.) in Canada with less than nine cases reported each year (2011)(2012)(2013).An increase in S. Reading was identified in several Canadian provinces in early 2015, prompting the initiation of a national outbreak investigation.Objectives: To describe a multi-provincial S. Reading outbreak in Canada that affected over 30 people.Methods: Cases were defined as laboratory-confirmed S. Reading with related pulsed-field gel electrophoresis (PFGE) patterns.Onset dates were between November 2014 and September 2015.Early in the investigation, investigators noted cases were predominantly of Eastern Mediterranean origin, mainly Afghan and Lebanese and many of those affected had consumed food items not typically captured on standard enteric outbreak hypothesis-generating questionnaires.An open-ended three day food consumption survey was conducted with a convenience sample of community informants to better understand food preferences of the affected ethnocultural populations.Results of the survey were used to design a focused questionnaire for case re-interviews and subsequent outbreak cases.Public health investigators obtained food samples from case homes and relevant food premises.Food safety authorities conducted traceback of suspected food items and collected food samples for laboratory testing.Results: There were 31 confirmed cases (Ontario=23, Alberta=7, New Brunswick=1) and three probable (Ontario=2, Alberta=1) cases of S. Reading identified as part of the outbreak.The median age was 31 years (range less than one to 85 years) and 53% (18/34) of cases were female.Seven cases were hospitalized.No deaths were reported.Most cases were of Eastern Mediterranean origin (n=23) or had reported consuming Eastern Mediterranean foods (n=3).The predominant ethnic origins reported by cases were Afghan in Ontario (n=12) and Lebanese in Alberta (n=3).Genetic similarity of clinical isolates was further confirmed using whole genome sequencing.Three ethnic bakeries were identified as possible common exposures for the cases; however, traceback of foods of interest from these bakeries did not identify a common supplier and the source of the illness was not identified.In total, 227 food samples from retail premises (n=142), restaurants (n=13) and case homes (n=72) were tested; two food samples, kalonji seeds and tahini, were positive for S. Ruiru and S. Meleagridis.These products were recalled from the marketplace.Conclusion: Despite extensive epidemiological, microbiological and food traceback investigations, a common source was not identified for this S. Reading outbreak.Challenges included lack of familiarity with the food items consumed in affected ethnocultural groups, as well as a lack of background data on expected food exposures in the outbreak population.Engaging local partners helped build understanding of food preferences in affected communities.Given Canada's ethnic and cultural diversity, culturally competent approaches to enteric outbreak investigations and food consumption surveys may be useful.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.004 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".