Estimating the burden of illness caused by domestic waterborne Legionnaires' disease in Canada: 2015-2019.

Legionellosis is a disease caused by the bacterium Legionella that most commonly presents as Legionnaires' disease (LD), a severe form of pneumonia. From 2015 to 2019, an average of 438 LD cases per year were reported in Canada. However, it is believed that the actual number of cases is much higher, since LD may be underdiagnosed and underreported. The purpose of this study was to develop an estimate of the true incidence of illnesses, hospitalizations, and deaths associated with LD in Canada. Values were derived using a stochastic model, based on Canadian surveillance data from 2015 to 2019, which were scaled up to account for underdiagnosis and underreporting. Overall, there were an estimated 1,113 (90% CrI: 737-1,730) illnesses, 1,008 (90% CrI: 271-2,244) hospitalizations, and 34 (90% CrI: 4-86) deaths due to domestically acquired waterborne LD annually in Canada from 2015 to 2019. It was further estimated that only 36% of illnesses and 39% of hospitalizations and deaths were captured in surveillance, and that 22% of illnesses were caused by Legionella serogroups and species other than Legionella pneumophila serogroup 1 (non-Lp1). This study highlights the true burden and areas for improvement in Canada's surveillance and detection of LD.

Impact of the COVID-19 Pandemic on the Reported Incidence of Select Bacterial Enteric Diseases in Canada, 2020.

The aim of this study was to describe the impact of the COVID-19 pandemic on reported cases and clusters of select enteric diseases in Canada, for the period of March 2020 to December 2020. Weekly counts of laboratory confirmed cases of Salmonella, Shigella, Shiga toxin-producing Escherichia coli (STEC), and Listeria monocytogenes were obtained from laboratory surveillance data. These data were supplemented with epidemiological information on the suspected source of illness, collected for cases identified within whole genome sequencing clusters. Incidence rate ratios were calculated for each pathogen. All data were compared with a prepandemic reference period. Decreases in the number of reported cases in 2020 compared with the previous 5-year period were noted for Salmonella, Shigella, Escherichia coli O157, and non-O157 STEC. Reported number of cases for L. monocytogenes in 2020 remained similar to those of the previous 5-year period. There was a considerable decline (59.9%) in the number of cases associated with international travel compared with a 10% decline in the number of domestic cases. Comparison of reported incidence rates of clustered versus sporadic cases for each pathogen showed little variation. This study represents the first formal assessment of the impact of COVID-19 on reported enteric diseases in Canada. Reported case counts across several pathogens saw notable declines in 2020 compared with prepandemic levels, with restrictions on international travel playing a key role. Additional research is needed to understand how limitations on social gatherings, lock downs, and other public health measures have impacted enteric diseases.

Estimated Reduction in the Burden of Nontyphoidal Salmonella Illness in Canada Circa 2019.

Nontyphoidal Salmonella (NTS) is a leading cause of acute gastrointestinal illness in Canada, and reported cases have been on the rise since the early 2000s. To address this trend, agri-food industry partners and government have worked to identify and implement interventions, guided by the enhanced information provided by whole-genome sequencing, to reduce the incidence of NTS. A substantial reduction in the number of NTS cases reported occurred in 2019. Due to underreporting and underdiagnosis factors, the observed decrease in the number of reported cases represents a fraction of the true number of illnesses averted in the community. The objective of this study was to: (1) use burden of illness estimation methodologies to estimate the true number of NTS illnesses, hospitalizations, and deaths prevented, and (2) estimate the economic savings associated with the prevention of these cases. Compared with the previous 5 years, there were an estimated 25,821 fewer illnesses, 213 fewer hospitalizations, and 2 fewer deaths attributable to NTS in 2019. This corresponds to an estimated reduction of 26.9 million Canadian dollars in the economic burden of NTS. Although causality cannot be proven by this study, the findings are suggestive that the strategically implemented suite of public health actions, including genomic-based surveillance, policy changes, and interventions by the government and industry, were successful in reducing the economic and health burden of NTS infections in Canada.

Consumption of High-Risk Foods in the Canadian Population, Foodbook Study, 2014 to 2015.

ABSTRACT: Many foods have the potential to cause foodborne illness; however, some pose a higher risk. Data were collected through the Foodbook study, a population-based telephone survey conducted between 2014 and 2015 that assessed 10,942 Canadians' food exposures using a 7-day recall period. The 19 foods included in the survey were identified as high risk for common foodborne pathogens in Canada. Results were analyzed by age group, gender, region of residence, income, and education. Consumption proportions of high-risk foods ranged from 0.4% (raw oysters) to 49.3% (deli meats). Roughly 94% of the population reported consuming one or more high-risk food in the past week. Certain high-risk food behaviors were associated with demographic characteristics. High-risk adults such as those 65 years or older still report consuming high-risk foods of concern, including deli meats (41.8%), soft cheeses (13.7%), and smoked fish (6.3%). Consumption of certain foods differed between genders, with males consuming significantly more deli meats, hot dogs, and raw or undercooked eggs and females consuming significantly more prebagged mixed salad greens. The overall number of high-risk foods consumed was similar, with both genders most frequently consuming three to five high-risk foods. High-risk food consumption was seen to increase with increasing household income, with 14.2% of the highest income level consuming six-plus high-risk foods in the past week, compared with 7.1% of the lowest income level. If a respondent had heard of a risk of foodborne illness associated with a food, it did not affect whether it was consumed. Additional consumer food safety efforts put in place alongside current messaging may improve high-risk food consumption behaviors. Enhancing current messaging by using multifaceted communications (e.g., social media and information pamphlets) and highlighting the large incidence and severity of foodborne illnesses in Canada are important strategies to improve behavior change.

Measuring animal exposure in Canada: Foodbook study, 2014-2015.

Animal companionship can have many physical and psychological benefits; however, animals can also be a source of zoonotic infection, including enteric illnesses; it has been estimated that in Canada, nearly 85,000 enteric illnesses due to eight pathogens occur each year related to animal contact. There is a lack of baseline data on animal-related exposures in Canada and around the world. This information is critical to inform quantitative and qualitative risk assessments to prioritize intervention efforts in public health and reduce the associated burden of enteric illness. To help address this issue and assist evaluation of the risks associated with animal contact, the Foodbook study, conducted in 2014-2015, assessed exposure to animals, animal food and animal-related venues within the last 7 days among Canadians. Data were analysed by province and territory, age group and urban/rural residency. Overall, dogs and cats were the most commonly reported animal exposures (43.3% and 31.9%, respectively). The data suggest farm animal exposure occurs primarily at a farm/barn, and to a lesser extent at other animal-related venues (e.g., petting zoos or agricultural fairs). Approximately one in 25 respondents handled raw pet food within the last 7 days; the majority of which had also been exposed to a dog (86.4%). Children aged 0-9 years reported relatively high exposure to four types of high-risk animals: rodents (5.6%), poultry (4.0%), reptiles (2.1%) and amphibians (1.8%); with the most vulnerable children aged <5 years also reporting exposure to many of these high-risk animals. These results highlight potential areas for targeted intervention that can focus on high-risk populations (e.g., young children) exhibiting potentially risky behaviour such as being exposed to certain high-risk animals, or handling pet food, treats and raw pet food diets. Additionally, these results support the need to better understand the burden of enteric illness associated with animals and their environments.

Canadian Consumer Food Safety Practices and Knowledge: Foodbook Study.

Understanding consumers' food safety practices and knowledge supports food safety education for the prevention of foodborne illness. The objective of this study was to describe Canadian consumer food safety practices and knowledge. This study identifies demographic groups for targeted food safety education messaging and establishes a baseline measurement to assess the effectiveness of food safety interventions over time. Questions regarding consumer food safety practices and knowledge were included in a population-based telephone survey, Foodbook, conducted from November 2014 to March 2015. The results were analyzed nationally by age group and by gender. The results showed that approximately 90% of Canadians reported taking the recommended cleaning and separating precautions when handling raw meat to prevent foodborne illness. Only 29% of respondents reported using a food thermometer when cooking any meat, and even fewer (12%) reported using a food thermometer for small cuts of meat such as chicken pieces. The majority (>80%) of Canadians were aware of the foodborne illness risks related to chicken and hamburger, but fewer (<40%) were aware of the risks related to frozen chicken nuggets, alfalfa sprouts, soft unpasteurized cheese, and unpasteurized juices. Generally, men were less likely to follow cooking instructions on packaging and took fewer steps to prevent cross-contamination than women. The youngest (18 to 29 years) age group was less likely to take steps to avoid cross-contamination and was less aware of the risks associated with eating an undercooked hamburger. The oldest (60+ years) respondents were less likely to be aware of the risks associated with raw eggs, alfalfa sprouts, and unpasteurized juice than the middle (30 to 59 years) age group. As a priority, food safety education in Canada should focus on increasing people's awareness of high-risk foods, specifically foods for which the awareness of risk found in this study was low; targeting messaging to demographic groups as appropriate; and promoting the use of food thermometers when cooking meat and poultry.

The Incidence of Acute Gastrointestinal Illness in Canada, Foodbook Survey 2014-2015.

Acute gastrointestinal illness (AGI) is an important public health issue, with many pathogen sources and modes of transmission. A one-year telephone survey was conducted in Canada (2014-2015) to estimate the incidence of self-reported AGI in the previous 28 days and to describe health care seeking behaviour, using a symptom-based case definition. Excluding cases with respiratory symptoms, it is estimated that there are 0.57 self-reported AGI episodes per person-year, almost 19.5 million episodes in Canada each year. The proportion of cases seeking medical care was nearly 9%, of which 17% reported being requested to submit a sample for laboratory testing, and 49% of those requested complied and provided a sample. Results can be used to inform burden of illness and source attribution studies and indicate that AGI continues to be an important public health issue in Canada.

Estimating the Relative Role of Various Subcategories of Food, Water, and Animal Contact Transmission of 28 Enteric Diseases in Canada.

OBJECTIVE: Enteric illness represents a significant burden of illness in Canada and internationally. Building on previous research, an expert elicitation was undertaken to explore the routes of transmission for 28 pathogens involved in enteric illness in Canada. This article considers the subcategories of foodborne, waterborne, and animal contact transmission. METHODS: As part of an expert elicitation, 31 experts were asked to provide estimates of source attribution for subcategories of foodborne (n = 15), waterborne (n = 10), and animal contact (n = 3) transmission. The results from an online survey were combined using triangular probability distributions, and median and 90% credible intervals were produced. The total proportion and estimated number of cases of enteric illness attributable to each type of food commodity, water source, and animal exposure route were calculated using results from the larger elicitation survey and from a recent Canadian foodborne burden of illness study (Thomas et al., 2013). RESULTS: Thirty experts provided foodborne subcategory estimates for 15/28 pathogens, waterborne subcategory estimates for 14/28 pathogens and animal contact subcategory estimates for 5/28. The elicitation identified raw produce, recreational water, and farm animal contact as important risk factors for enteric illness. These results also highlighted the complexity of transmission, with greater uncertainty for certain pathogens and routes of transmission. CONCLUSIONS: This study is the first of its kind to explore subcategories of foodborne, waterborne, and animal contact transmission across such a range of enteric pathogens. Despite inherent uncertainty, these estimates present an important quantitative synthesis of the roles of foodborne commodities, water sources, and pathways of animal contact in the transmission of enteric illness in Canada.

A Systematic Review and Meta-Analysis of the Campylobacter spp. Prevalence and Concentration in Household Pets and Petting Zoo Animals for Use in Exposure Assessments.

Animal contact is a potential transmission route for campylobacteriosis, and both domestic household pet and petting zoo exposures have been identified as potential sources of exposure. Research has typically focussed on the prevalence, concentration, and transmission of zoonoses from farm animals to humans, yet there are gaps in our understanding of these factors among animals in contact with the public who don't live on or visit farms. This study aims to quantify, through a systematic review and meta-analysis, the prevalence and concentration of Campylobacter carriage in household pets and petting zoo animals. Four databases were accessed for the systematic review (PubMed, CAB direct, ProQuest, and Web of Science) for papers published in English from 1992-2012, and studies were included if they examined the animal population of interest, assessed prevalence or concentration with fecal, hair coat, oral, or urine exposure routes (although only articles that examined fecal routes were found), and if the research was based in Canada, USA, Europe, Australia, and New Zealand. Studies were reviewed for qualitative synthesis and meta-analysis by two reviewers, compiled into a database, and relevant studies were used to create a weighted mean prevalence value. There were insufficient data to run a meta-analysis of concentration values, a noted study limitation. The mean prevalence of Campylobacter in petting zoo animals is 6.5% based on 7 studies, and in household pets the mean is 24.7% based on 34 studies. Our estimated concentration values were: 7.65x103cfu/g for petting zoo animals, and 2.9x105cfu/g for household pets. These results indicate that Campylobacter prevalence and concentration are lower in petting zoo animals compared with household pets and that both of these animal sources have a lower prevalence compared with farm animals that do not come into contact with the public. There is a lack of studies on Campylobacter in petting zoos and/or fair animals in Canada and abroad. Within this literature, knowledge gaps were identified, and include: a lack of concentration data reported in the literature for Campylobacter spp. in animal feces, a distinction between ill and diarrheic pets in the reported studies, noted differences in shedding and concentrations for various subtypes of Campylobacter, and consistent reporting between studies.

Methodological Framework for World Health Organization Estimates of the Global Burden of Foodborne Disease.

BACKGROUND: The Foodborne Disease Burden Epidemiology Reference Group (FERG) was established in 2007 by the World Health Organization to estimate the global burden of foodborne diseases (FBDs). This paper describes the methodological framework developed by FERG's Computational Task Force to transform epidemiological information into FBD burden estimates. METHODS AND FINDINGS: The global and regional burden of 31 FBDs was quantified, along with limited estimates for 5 other FBDs, using Disability-Adjusted Life Years in a hazard- and incidence-based approach. To accomplish this task, the following workflow was defined: outline of disease models and collection of epidemiological data; design and completion of a database template; development of an imputation model; identification of disability weights; probabilistic burden assessment; and estimating the proportion of the disease burden by each hazard that is attributable to exposure by food (i.e., source attribution). All computations were performed in R and the different functions were compiled in the R package 'FERG'. Traceability and transparency were ensured by sharing results and methods in an interactive way with all FERG members throughout the process. CONCLUSIONS: We developed a comprehensive framework for estimating the global burden of FBDs, in which methodological simplicity and transparency were key elements. All the tools developed have been made available and can be translated into a user-friendly national toolkit for studying and monitoring food safety at the local level.

Economic Cost of a Listeria monocytogenes Outbreak in Canada, 2008.

Estimates of the economic costs associated with foodborne disease are important to inform public health decision-making. In 2008, 57 cases of listeriosis and 24 deaths in Canada were linked to contaminated delicatessen meat from one meat processing plant. Costs associated with the cases (including medical costs, nonmedical costs, and productivity losses) and those incurred by the implicated plant and federal agencies responding to the outbreak were estimated to be nearly $242 million Canadian dollars (CAD, 2008). Case costs alone were estimated at approximately $2.8 million (CAD, 2008) including loss of life. This demonstrates the considerable economic burden at both the individual and population levels associated with foodborne disease and foodborne outbreaks in particular. Foodborne outbreaks due to severe pathogens, such as Listeria monocytogenes and those that result in product recalls, are typically the most costly from the individual and/or societal perspective. Additional economic estimates of foodborne disease would contribute to our understanding of the burden of foodborne disease in Canada and would support the need for ongoing prevention and control activities.

Estimates of foodborne illness-related hospitalizations and deaths in Canada for 30 specified pathogens and unspecified agents.

Foodborne illness estimates help to set food safety priorities and create public health policies. The Public Health Agency of Canada estimates that 4 million episodes of foodborne illness occur each year in Canada due to 30 known pathogens and unspecified agents. The main objective of this study was to estimate the number of domestically acquired foodborne illness-related hospitalizations and deaths. Using the estimates of foodborne illness for Canada along with data from the Canadian Hospitalization Morbidity Database (for years 2000-2010) and relevant international literature, the number of hospitalizations and deaths for 30 pathogens and unspecified agents were calculated. Analysis accounted for under-reporting and underdiagnosis. Estimates of the proportion foodborne and the proportion travel-related were incorporated for each pathogen. Monte Carlo simulations were performed to account for uncertainty generating mean estimates and 90% probability intervals. It is estimated that each year there are 4000 hospitalizations (range 3200-4800) and 105 (range 75-139) deaths associated with domestically acquired foodborne illness related to 30 known pathogens and 7600 (range 5900-9650) hospitalizations and 133 (range 77-192) deaths associated with unspecified agents, for a total estimate of 11,600 (range 9250-14,150) hospitalizations and 238 (range 155-323) deaths associated with domestically acquired foodborne illness in Canada. Key pathogens associated with these hospitalizations or deaths include norovirus, nontyphoidal Salmonella spp., Campylobacter spp., VTEC O157 and Listeria monocytogenes. This is the first time Canada has established pathogen-specific estimates of domestically acquired foodborne illness-related hospitalizations and deaths. This information illustrates the substantial burden of foodborne illness in Canada.

Healthcare use for acute gastrointestinal illness in two Inuit communities: Rigolet and Iqaluit, Canada.

BACKGROUND: The incidence of self-reported acute gastrointestinal illness (AGI) in Rigolet, Nunatsiavut, and Iqaluit, Nunavut, is higher than reported elsewhere in Canada; as such, understanding AGI-related healthcare use is important for healthcare provision, public health practice and surveillance of AGI. OBJECTIVES: This study described symptoms, severity and duration of self-reported AGI in the general population and examined the incidence and factors associated with healthcare utilization for AGI in these 2 Inuit communities. DESIGN: Cross-sectional survey data were analysed using multivariable exact logistic regression to examine factors associated with individuals' self-reported healthcare and over-the-counter (OTC) medication utilization related to AGI symptoms. RESULTS: In Rigolet, few AGI cases used healthcare services [4.8% (95% CI=1.5-14.4%)]; in Iqaluit, some cases used healthcare services [16.9% (95% CI=11.2-24.7%)]. Missing traditional activities due to AGI (OR=3.8; 95% CI=1.18-12.4) and taking OTC medication for AGI symptoms (OR=3.8; 95% CI=1.2-15.1) were associated with increased odds of using healthcare services in Iqaluit. In both communities, AGI severity and secondary symptoms (extreme tiredness, headache, muscle pains, chills) were significantly associated with increased odds of taking OTC medication. CONCLUSIONS: While rates of self-reported AGI were higher in Inuit communities compared to non-Inuit communities in Canada, there were lower rates of AGI-related healthcare use in Inuit communities compared to other regions in Canada. As such, the rates of healthcare use for a given disease can differ between Inuit and non-Inuit communities, and caution should be exercised in making comparisons between Inuit and non-Inuit health outcomes based solely on clinic records and healthcare use.

Systematic review of expert elicitation methods as a tool for source attribution of enteric illness.

Expert elicitation is a useful tool to explore sources of uncertainty and to answer questions where data are expensive or difficult to collect. It has been used across a variety of disciplines and represents an important method for estimating source attribution for enteric illness. A systematic review was undertaken to explore published expert elicitation studies, identify key considerations, and to make recommendations for designing an expert elicitation in the context of enteric illness source attribution. Fifty-nine studies were reviewed. Five key themes were identified: the expert panel including composition and recruitment; the pre-elicitation material, which clarifies the research question and provides training in uncertainty and probability; the choice of elicitation tool and method (e.g., questionnaires, surveys, and interviews); research design; and analysis of elicited data. Careful consideration of these themes is critical in designing and implementing an expert elicitation in order to reduce bias and produce the best possible results. While there are various epidemiological and microbiological methods available to explore source attribution of enteric illness, expert elicitation provides an opportunity to identify gaps in our understanding and where such studies are not feasible or available, represents the only possible method for synthesizing knowledge about transmission.

Expert elicitation as a means to attribute 28 enteric pathogens to foodborne, waterborne, animal contact, and person-to-person transmission routes in Canada.

Enteric illness contributes to a significant burden of illness in Canada and globally. Understanding its sources is a critical step in identifying and preventing health risks. Expert elicitation is a powerful tool, used previously, to obtain information about enteric illness source attribution where information is difficult or expensive to obtain. Thirty-one experts estimated transmission of 28 pathogens via major transmission routes (foodborne, waterborne, animal contact, person-to-person, and other) at the point of consumption. The elicitation consisted of a (snowball) recruitment phase; administration of a pre-survey to collect background information, an introductory webinar, an elicitation survey, a 1-day discussion, survey readministration, and a feedback exercise, and surveys were administered online. Experts were prompted to quantify changes in contamination at the point of entry into the kitchen versus point of consumption. Estimates were combined via triangular probability distributions, and medians and 90% credible-interval estimates were produced. Transmission was attributed primarily to food for Bacillus cereus, Clostridium perfringens, Cyclospora cayetanensis, Trichinella spp., all three Vibrio spp. categories explored, and Yersinia enterocolitica. Multisource pathogens (e.g., transmitted commonly through both water and food) such as Campylobacter spp., four Escherichia coli categories, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were also estimated as mostly foodborne. Water was the primary pathway for Giardia spp. and Cryptosporidium spp., and person-to-person transmission dominated for six enteric viruses and Shigella spp. Consideration of the point of attribution highlighted the importance of food handling and cross-contamination in the transmission pathway. This study provides source attribution estimates of enteric illness for Canada, considering all possible transmission routes. Further research is necessary to improve our understanding of poorly characterized pathogens such as sapovirus and E. coli subgroups in Canada.

Lived experience of acute gastrointestinal illness in Rigolet, Nunatsiavut: "just suffer through it".

Enteric illness associated with foodborne and waterborne disease is thought to be common in some Canadian Indigenous communities. This study aimed to understand the lived experience of acute gastrointestinal illness (AGI), including symptoms and severity, perceived causes, and healthcare seeking behaviors of AGI in the small Inuit community of Rigolet, Canada. A concurrent mixed quantitative and qualitative methods design was used. Two cross-sectional retrospective surveys provided quantitative data to examine self-reported AGI symptoms and the distribution of potential risk factors in the community. Qualitative data from in-depth interviews with one-third of AGI cases were analyzed using a constant-comparative method to describe symptoms and severity, identify perceived risk factors, and explore health seeking behavior of AGI in Rigolet. Of the survey respondents reporting AGI, most reported symptoms of diarrhea without vomiting, followed by diarrhea with vomiting, and vomiting without diarrhea. The most common secondary symptoms included stomach cramps and abdominal pain, nausea, and extreme tiredness. Community members identified potential risk factors for AGI that reflect the epidemiology triad (host, agent, and environmental factors), including hygiene, retail food, tap water, boil water advisories, and personal stress. Risk aversion and healthcare seeking behaviors reflected the core constructs of the Health Belief Model (perceived susceptibility, severity, and benefits and barriers to action). Understanding community experience, perspectives, and beliefs related to AGI is useful for public health practitioners and health care providers. This information is important especially considering the relatively high estimated burden of AGI and the relatively low healthcare seeking behaviors in some Indigenous communities compared to national estimates. Moreover, the mixed-methods approach used to understand the burden of AGI could be extended to other health research in Indigenous contexts.

Systematic review and meta-analysis of the proportion of Campylobacter cases that develop chronic sequelae.

BACKGROUND: Understanding of chronic sequelae development after Campylobacter infection is limited. The objective of the study was to determine via systematic review and meta-analysis the proportion of Campylobacter cases that develop chronic sequelae. METHODS: A systematic review of English language articles published prior to July 2011 located using Pubmed, Agricola, CabDirect, and Food Safety and Technology Abstracts. Observational studies reporting the number of Campylobacter cases that developed reactive arthritis (ReA), Reiter's syndrome (RS), haemolytic uraemic syndrome (HUS), irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) ,Guillain Barré syndrome (GBS) or Miller Fisher syndrome (MFS) were included. Data extraction through independent extraction of articles by four reviewers (two per article). Random effects meta-analysis was performed and heterogeneity was assessed using the I(2) value. Meta-regression was used to explore the influence of study level variables on heterogeneity. RESULTS: A total of 31 studies were identified; 20 reported on ReA, 2 reported on RS, 9 reported on IBS, 3 studies reported on IBD, 8 reported on GBS, 1 reported on MFS and 3 reported on HUS. The proportion of Campylobacter cases that developed ReA was 2.86% (95% CI 1.40% - 5.61%, I(2) = 97.7%), irritable bowel syndrome was 4.01% (95% CI 1.41% - 10.88%, I(2) = 99.2%). Guillain Barré syndrome was 0.07% (95% CI 0.03% - 0.15%, I(2) = 72.7%). CONCLUSIONS: A significant number of Campylobacter cases develop a chronic sequela. However, results should be interpreted with caution due to the high heterogeneity.

Estimating the number of human cases of ceftiofur-resistant Salmonella enterica serovar Heidelberg in Québec and Ontario, Canada.

A stochastic model was used to estimate the number of human cases of ceftiofur-resistant Salmonella enterica serovar Heidelberg in Québec and Ontario attributable to chicken consumption and excess cases attributable to human prior antimicrobial consumption. The annual mean incidence of S. Heidelberg (Québec/Ontario) decreased from 70/62 cases per 100 000 in 2004 to 29/30 cases per 100 000 in 2007 (Québec)/2008 (Ontario), increasing to 59/45 cases per 100 000 in 2011. The annual mean incidence of ceftiofur-resistant cases from chicken decreased from 8/7 cases per 100 000 in 2004 to 1/1 cases per 100 000 in 2007 (Québec)/2008 (Ontario), increasing to 7/5 cases per 100 000 in 2011. The annual mean total number of excess ceftiofur-resistant cases from chicken attributable to human prior antimicrobial consumption (Québec/Ontario) decreased from 71/123 in 2004 to 6/24 in 2007 (Québec)/2008 (Ontario), but increased to 62/91 in 2011. This model will support future work to determine the increased severity, mortality and healthcare costs for ceftiofur-resistant Salmonella Heidelberg infections. These results provide a basis for the evaluation of future public health interventions to address antimicrobial resistance.

Component costs of foodborne illness: a scoping review.

BACKGROUND: Governments require high-quality scientific evidence to prioritize resource allocation and the cost-of-illness (COI) methodology is one technique used to estimate the economic burden of a disease. However, variable cost inventories make it difficult to interpret and compare costs across multiple studies. METHODS: A scoping review was conducted to identify the component costs and the respective data sources used for estimating the cost of foodborne illnesses in a population. This review was accomplished by: (1) identifying the research question and relevant literature, (2) selecting the literature, (3) charting, collating, and summarizing the results. All pertinent data were extracted at the level of detail reported in a study, and the component cost and source data were subsequently grouped into themes. RESULTS: Eighty-four studies were identified that described the cost of foodborne illness in humans. Most studies (80%) were published in the last two decades (1992-2012) in North America and Europe. The 10 most frequently estimated costs were due to illnesses caused by bacterial foodborne pathogens, with non-typhoidal Salmonella spp. being the most commonly studied. Forty studies described both individual (direct and indirect) and societal level costs. The direct individual level component costs most often included were hospital services, physician personnel, and drug costs. The most commonly reported indirect individual level component cost was productivity losses due to sick leave from work. Prior estimates published in the literature were the most commonly used source of component cost data. Data sources were not provided or specifically linked to component costs in several studies. CONCLUSIONS: The results illustrated a highly variable depth and breadth of individual and societal level component costs, and a wide range of data sources being used. This scoping review can be used as evidence that there is a lack of standardization in cost inventories in the cost of foodborne illness literature, and to promote greater transparency and detail of data source reporting. By conforming to a more standardized cost inventory, and by reporting data sources in more detail, there will be an increase in cost of foodborne illness research that can be interpreted and compared in a meaningful way.