A descriptive study of reportable gastrointestinal illnesses in Ontario, Canada, from 2007 to 2009

Abstract

BackgroundGastrointestinal illnesses (GI) continue to pose a substantial burden in terms of morbidity and economic impact in Canada. We describe the epidemiology of reportable GI in Ontario by characterizing the incidence of each reportable GI, as well as associated demographics, clinical outcomes, seasonality, risk settings, and likely sources of infection.MethodsReports on laboratory confirmed cases of amebiasis, botulism, campylobacteriosis, cryptosporidiosis, cyclosporiasis, giardiasis, hepatitis A, listeriosis, paratyphoid fever, salmonellosis, shigellosis, typhoid fever, illness due to verotoxin-producing Escherichia coli (VTEC-illness), and yersiniosis, from January 1, 2007 to December 31, 2009 were obtained from Ontario’s passive reportable disease surveillance system. Cases were classified by history of relevant travel, association with outbreaks, and likely source of infection, obtained through follow-up of reported cases by local health authorities.ResultsThere were 29,897 GI reported by health authorities in Ontario from 2007 to 2009. The most frequently reported diseases were campylobacteriosis (10,916 cases or 36.5% of all GI illnesses) and salmonellosis (7,514 cases, 25.1%). Overall, 26.9% of GI cases reported travel outside of Ontario during the relevant incubation period. Children four years of age and younger had the highest incidence rate for most GI, and significantly more (54.8%, p<0.001) cases occurred among males than females. The most commonly reported sources of infections were food (54.2%), animals (19.8%), and contact with ill persons (16.9%). Private homes (45.5%) and food premises (29.7%) were the most commonly reported exposure settings. Domestic cases of campylobacteriosis, cryptosporidiosis, giardiasis, salmonellosis, and VTEC-illness showed seasonal patterns with incidence peaking in the summer months.ConclusionsReportable GI continues to be a burden in Ontario. Since more than one in four GI cases experienced in Ontario were acquired outside of the province, international travel is an important risk factor for most GI. Because private homes are the most commonly reported risk settings and the main suspect sources of infection are food, animal contact and ill persons, these findings support the continued need for public health food safety programs, public education on safe handling of food and animals, and proper hand hygiene practices.

Detection and Prevalence of Verotoxin-Producing Escherichia coli O157 and Non-O157 Serotypes in a Canadian Watershed

“…While the trend was not statistically significant, samples were more frequently positive for VTEC in the winter and spring months than in the fall and summer months. This study was not designed to elucidate predictors for seasonality of this pathogen, but others suggest that some common land use management practices, as well as the seasonal dynamics of human infections, which contribute to wastewater loading levels, could contribute to seasonal trends (39), although the seasonality in water appears to be different from the seasonality in human infections, which shows a summer peak (42). Knowledge of seasonal trends at the watershed level could help inform interventions that will minimize impacts on the watercourse through the control of land use activities such as manure runoff to surface waters and septic tank leakage, as well as highlighting the need for additional treatment of wastewater.…”

Barriers and Facilitators to Safe Food Handling among Consumers: A Systematic Review and Thematic Synthesis of Qualitative Research Studies

“…However, previous research suggests that most sporadic cases of enteric illness are associated with exposure at home vs. other settings [7–9], and most foodborne disease outbreaks in Europe are associated with domestic household settings [10]. Several previous qualitative research studies have been conducted to investigate consumers’ perspectives, opinions, and experiences with safe food handling at home [11–13].…”

Estimates of the burden of illness for eight enteric pathogens associated with animal contact in Canada

“…This is likely due to the differences in total illness estimates as well as generally lower proportions of illness estimated to be via animal transmission in the USA, which relied primarily on case-control studies and outbreak summaries to inform the US inputs. The values used for the proportion of illness attributed to animal contact in Canada from the expert elicitation are within the range of values reported in international studies from the USA, Australia and the Netherlands [31,33,34,36] as well as Canadian studies, using surveillance data and reported exposures [32,48,49] (Table 5).…”

“…Reported case data from the province of Ontario, Canada, identified contact with animals as the primary source of exposure for nearly 20% of the reported cases due to 14 pathogens [32]. Estimating transmission routes for enteric pathogens is difficult due to the lack of data.…”