Case Series of Jamestown Canyon Virus Infections with Neurologic Outcomes, Canada, 2011-2016.

Jamestown Canyon virus (JCV) is a mosquitoborne orthobunyavirus in the California serogroup that circulates throughout Canada and the United States. Most JCV exposures result in asymptomatic infection or a mild febrile illness, but JCV can also cause neurologic diseases, such as meningitis and encephalitis. We describe a case series of confirmed JCV-mediated neuroinvasive disease among persons from the provinces of British Columbia, Alberta, Quebec, and Nova Scotia, Canada, during 2011-2016. We highlight the case definitions, epidemiology, unique features and clinical manifestations, disease seasonality, and outcomes for those cases. Two of the patients (from Quebec and Nova Scotia) might have acquired JCV infections during travel to the northeastern region of the United States. This case series collectively demonstrates JCV's wide distribution and indicates the need for increased awareness of JCV as the underlying cause of meningitis/meningoencephalitis during mosquito season.

Descriptive study of enteric zoonoses in Ontario, Canada, from 2010 - 2012.

BACKGROUND: Contact with animals and their environment has long been recognized as an important source of enteric zoonoses. However, there are limited data available on the burden of illness associated with specific types of animals in Canada. This study describes the overall burden of enteric zoonoses in Ontario, Canada from 2010 to 2012. METHODS: Confirmed cases of seven enteric zoonotic diseases (campylobacteriosis, cryptosporidiosis, giardiasis, listeriosis, salmonellosis, verotoxin-producing E. coli (VTEC) infection, and yersiniosis) with episode dates from 2010 to 2012 were extracted from the integrated Public Health Information System (iPHIS). Reported exposures were categorized as animal contact, foodborne, waterborne and 'other', with animal contact grouped into nine sub-categories based on the type of animal or transmission setting. Overall incidence rates and proportions by animal exposure categories, age and sex-specific incidence rates and hospitalization and death proportions were calculated and sex proportions compared. RESULTS: Our study found that approximately 26% of the enteric pathogens assessed during the 2010 to 2012 period reported contact with animals and their environments as the mode of transmission. Of enteric disease cases reporting animal contact, farm exposures were reported for 51.3%, dog or cat exposures for 26.3%, and reptile or amphibian exposures for 8.9%. CONCLUSIONS: Contact with animals was reported more frequently during the period 2010 to 2012 in comparison to the period 1997 to 2003 when 6% or less of enteric cases were associated with animal contact. Public health professionals, stakeholders associated with animals and their related industries (e.g., pet treats, mobile zoos, abattoirs), and the public should recognize that animal contact is an important source of enteric illnesses in order to take measures to reduce the burden of illness from animal sources.

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

BACKGROUND: Gastrointestinal 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. METHODS: Reports 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. RESULTS: There 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. CONCLUSIONS: Reportable 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.

The epidemiology of travel-related Salmonella Enteritidis in Ontario, Canada, 2010-2011.

BACKGROUND: Increases in the number of salmonellosis cases due to Salmonella Enteritidis (SE) in 2010 and 2011 prompted a public health investigation in Ontario, Canada. In this report, we describe the current epidemiology of travel-related (TR) SE, compare demographics, symptoms and phage types (PTs) of TR and domestically-acquired (DA) cases, and estimate the odds of acquiring SE by region of the world visited. METHODS: All incident cases of culture confirmed SE in Ontario obtained from isolates and specimens submitted to public health laboratories were included in this study. Demographic and illness characteristics of TR and DA cases were compared. A national travel survey was used to provide estimates for the number of travellers to various destinations to approximate rates of SE in travellers. Multivariate logistic regression was used to estimate the odds of acquiring SE when travelling to various world regions. RESULTS: Overall, 51.9% of SE cases were TR during the study period. This ranged from 35.7% TR cases in the summer travel period to 65.1% TR cases in the winter travel period. Compared to DA cases, TR cases were older and were less likely to seek hospital care. For Ontario travellers, the adjusted odds of acquiring SE was the highest for the Caribbean (OR 37.29, 95% CI 17.87-77.82) when compared to Europe. Certain PTs were more commonly associated with travel (e.g., 1, 4, 5b, 7a, Atypical) than with domestic infection. Of the TR cases, 88.9% were associated with travel to the Caribbean and Mexico region, of whom 90.1% reported staying on a resort. Within this region, there were distinct associations between PTs and countries. CONCLUSIONS: There is a large burden of TR illness from SE in Ontario. Accurate classification of cases by travel history is important to better understand the source of infections. The findings emphasize the need to make travellers, especially to the Caribbean, and health professionals who provide advice to travellers, aware of this risk. The findings may be generalized to other jurisdictions with travel behaviours in their residents similar to Ontario residents.

An overview of the National West Nile Virus Surveillance System in Canada: A One Health approach.

National West Nile virus (WNV) surveillance was established in partnership with the federal, provincial and territorial governments starting in 2000, with the aim to monitor the emergence and subsequent spread of WNV disease in Canada. As the disease emerged, national WNV surveillance continued to focus on early detection of WNV disease outbreaks in different parts of the country. In Canada, the WNV transmission season occurs from May to November. During the season, the system adopts a One Health approach to collect, integrate, analyze and disseminate national surveillance data on human, mosquito, bird and other animal cases. Weekly and annual reports are available to the public, provincial/territorial health authorities, and other federal partners to provide an ongoing national overview of WNV infections in Canada. While national surveillance allows a jurisdiction-by-jurisdiction comparison of data, it also helps to guide appropriate disease prevention strategies such as education and awareness campaigns at the national level. This paper aims to describe both the establishment and the current structure of national WNV surveillance in Canada.

Detection of municipalities at-risk of Lyme disease using passive surveillance of Ixodes scapularis as an early signal: A province-specific indicator in Canada.

Lyme disease, the most commonly reported vector-borne disease in North America, is caused by the spirochete Borrelia burgdorferi sensu stricto, which is transmitted by Ixodes scapularis in eastern Canada and Ixodes pacificus in western Canada. Recently, the northward range expansion of I. scapularis ticks, in south-eastern Canada, has resulted in a dramatic increase in the incidence of human Lyme disease. Detecting emerging areas of Lyme disease risk allows public health to target disease prevention efforts. We analysed passive tick surveillance data from Ontario and Manitoba to i) assess the relationship between the total numbers of I. scapularis submissions in passive surveillance from humans, and the number of human Lyme disease cases, and ii) develop province-specific acarological indicators of risk that can be used to generate surveillance-based risk maps. We also assessed associations between numbers of nymphal I. scapularis tick submissions only and Lyme disease case incidence. Using General Estimating Equation regression, the relationship between I. scapularis submissions (total numbers and numbers of nymphs only) in each census sub-division (CSD) and the number of reported Lyme disease cases was positively correlated and highly significant in the two provinces (P ≤ 0.001). The numbers of I. scapularis submissions over five years discriminated CSDs with ≥ 3 Lyme disease cases from those with < 3 cases with high accuracy when using total numbers of tick submission (Receiver Operating Characteristics area under the curve [AUC] = 0.89) and moderate accuracy (AUC = 0.78) when using nymphal tick submissions only. In Ontario the optimal cut-off point was a total 12 tick submissions from a CSD over five years (Sensitivity = 0.82, Specificity = 0.84), while in Manitoba the cut-off point was five ticks (Sensitivity = 0.71, Specificity = 0.79) suggesting regional variability of the risk of acquiring Lyme disease from an I. scapularis bite. The performances of the acarological indicators developed in this study for Ontario and Manitoba support the ability of passive tick surveillance to provide an early signal of the existence Lyme disease risk areas in regions where ticks and the pathogens they transmit are expanding their range.

Evaluating the impact of Aedes japonicus invasion on the mosquito community in the Greater Golden Horseshoe region (Ontario, Canada).

BACKGROUND: Aedes japonicus was first documented in Ontario, Canada, in 2001. The objective of this study was to determine the effect of Ae. japonicus establishment on the abundance of other mosquitoes in the Greater Golden Horseshoe (GGH) region of Ontario. METHODS: Adult mosquito data from the Ontario West Nile virus surveillance program were used. Descriptive analyses, linear trends and distribution maps of average trap count per month for six mosquito species of interest were produced. Multivariable negative binomial regression models were constructed to 1) test whether the invasion of Ae. japonicus affected the abundance of other mosquitoes by comparing the time period before Ae. japonicus was identified in an area (pre-detection), to after it was first identified (detection), and subsequently (establishment), and 2) identify the variables that explain the abundance of the various mosquito species. RESULTS: The monthly seasonal average (May-October) of Ae. japonicus per trap night increased from 2002 to 2016, peaking in September, when the average of most other mosquitoes decrease. There were increased numbers of Ae. triseriatus/hendersoni (Odds Ratio (OR): 1.40, 95% Confidence Interval (CI): 1.02-1.94) and decreased numbers of Coquillettidia perturbans (OR: 0.43, 95% CI: 0.26-0.73) in the detection period, compared to the pre-detection period. Additionally, there was a decrease in Cx. pipiens/restuans (OR: 0.87, 95% CI: 0.76-0.99) and Cq. perturbans (OR: 0.68, 95% CI: 0.49-0.94) in the establishment period, compared to the pre-detection period. None of the most parsimonious explanatory models included the period of the establishment of Ae. japonicus. CONCLUSIONS: There is no evidence that the introduction of Ae. japonicus significantly reduced populations of Ae. triseriatus/hendersoni, Cx. pipiens/restuans or An. punctipennis in the GGH. While further research is needed to understand the impact of the Ae. japonicus invasion on other mosquito species, our work indicates that, on a regional scale, little impact has been noted.

A review of interventions triggered by hepatitis A infected food-handlers in Canada.

BACKGROUND: In countries with low hepatitis A (HA) endemicity, infected food handlers are the source of most reported foodborne outbreaks. In Canada, accessible data repositories of infected food handler incidents are not available. We undertook a systematic review of such incidents to evaluate the extent of viral transmission through food contamination and the scope of post-exposure prophylaxis (PEP) interventions. METHODS: A systematic search of MEDLINE and EMBASE was conducted to identify published reports of incidents in Canada. An expanded search of a news repository (i.e., transcripts from newspapers and newscasts) was also conducted to identify the location and timing of an incident, which was used to retrieve the related report by contacting local public health departments. Data pertaining to case identification, public health risk, PEP interventions, and associated costs was independently abstracted by two reviewers and summarized according to incidents with and without large PEP interventions. RESULTS: A total of 16 incidents were identified from 1998-2004. There were approximately 3 incidents requiring public notification per year. Only 12.5% of incidents were described in published reports, indicating that published data significantly underestimated the number of incidents and PEP interventions. Data pertaining to the remaining incidents was unpublished, sparse and highly dispersed at the local public health level. Six of the 16 incidents required large PEP interventions to immunize on average 5000 potentially exposed individuals. Secondary transmission was low. Characteristics of incidents requiring large PEP interventions included potentially infectious food handlers working with uncooked food for a prolonged duration in high-volume grocery stores in high-density urban areas. CONCLUSION: Infected food handlers with hepatitis A virus (HAV) requiring public notification are not infrequent in Canada. Published data severely underestimated the burden of PEP intervention. Better and consistent reporting at the local and national level as well as a national data repository should be considered for the management of future incidents.

Temporal analysis of acute myocardial infarction in Ontario, Canada.

BACKGROUND: Acute myocardial infarction (AMI) is a substantial cause of morbidity and mortality in Canada. Evidence suggests that the incidence and mortality of AMI increase in the winter. Determining the strength and nature of seasonality patterns in relation to age and sex may be helpful in health care planning. OBJECTIVES: To examine the seasonal patterns of AMI hospital admissions by age and sex, to assess the strength of the seasonal patterns and to examine the overall trends in admissions. METHODS: A retrospective population-based study was conducted to assess temporal patterns in 14 years of hospital admissions for AMI (from April 1, 1988, to March 31, 2002) in Ontario. Seasonality was assessed using the autoregression coefficient (R2Autoreg), and Fisher's Kappa and Bartlett's Kolmogorov-Smirnov tests. RESULTS: There were 271,321 people in the cohort, of whom 63% (n = 171,546) were male and 37% (n = 99,775) were female. There was an increase in AMI admissions since 1988 that reached a plateau in 1992, which was attributable mostly to the increased rate in the oldest age groups (70 years and older), where admission rates more than doubled. An association between seasonality and AMI admissions was found in most age and sex groups, with men consistently exhibiting a stronger seasonality pattern. The greatest difference in the cohort, 2.5 per 100,000 per month (134 admissions), occurred between December and September (13.64 per 100,000 in September versus 16.14 per 100,000 in December). CONCLUSIONS: AMI admissions show seasonality patterns, which are more pronounced in men. Although statistically significant, the seasonal differences are small in terms of absolute numbers, and are likely irrelevant in health care planning.

Does socioeconomic status affect mortality subsequent to hospital admission for community acquired pneumonia among older persons?

BACKGROUND: Low socioeconomic status has been associated with increased morbidity and mortality for various health conditions. The purpose of this study was twofold: to examine the mortality experience of older persons admitted to hospital with community acquired pneumonia and to test the hypothesis of whether an association exists between socioeconomic status and mortality subsequent to hospital admission for community-acquired pneumonia. METHODS: A population based retrospective cohort study was conducted including all older persons patients admitted to Ontario hospitals with community acquired pneumonia between April 1995 and March 2001. The main outcome measures were 30 day and 1 year mortality subsequent to hospital admission for community-acquired pneumonia. RESULTS: Socioeconomic status for each patient was imputed from median neighbourhood income. Multivariate analyses were undertaken to adjust for age, sex, co-morbid illness, hospital and physician characteristics. The study sample consisted of 60,457 people. Increasing age, male gender and high co-morbidity increased the risk for mortality at 30 days and one year. Female gender and having a family physician as attending physician reduced mortality risk. The adjusted odds of death after 30-days for the quintiles compared to the lowest income quintile (quintile 1) were 1.02 (95% CI: 0.95-1.09) for quintile 2, 1.04 (95% CI: 0.97-1.12) for quintile 3, 1.01 (95% CI: 0.94-1.08) for quintile 4 and 1.03 (95% CI: 0.96-1.12) for the highest income quintile (quintile 5). For 1 year mortality, compared to the lowest income quintile the adjusted odds ratios were 1.01 (95% CI: 0.96-1.06) for quintile 2, 0.99 (95% CI: 0.94-1.04) for quintile 3, 0.99 (95% CI: 0.93-1.05) for quintile 4 and 1.03 (95% CI: 0.97-1.10) for the highest income quintile. CONCLUSION: Socioeconomic status is not associated with mortality in the older persons from community-acquired pneumonia in Ontario, Canada.

Evaluation of the Do Bugs Need Drugs? program in British Columbia: Can we curb antibiotic prescribing?

OBJECTIVE: Antibiotic resistance is accelerated by the overuse of antibiotics. Do Bugs Need Drugs? is an educational program adapted in British Columbia to target both the public and health care professionals, with the aim of reducing unnecessary prescribing. The current article presents a descriptive evaluation of the impact of the program over the first four years. METHOD: Program implementation was measured by the amount of educational material distributed and the level of participation in educational sessions. The impact of the program was assessed by measuring changes in knowledge and prescribing habits of participating physicians, and by investigating provincial trends in antibiotic use. RESULTS: A total of 51,367 children, assisted-living residents and health care professionals have participated in the program since its inception in the fall of 2005. Pre- and postcourse assessments of participating physicians indicated significant improvements in clinical knowledge and appropriate antibiotic treatment of upper respiratory tract infections. Overall rates of antibiotic use in the province have stabilized since 2006. The rates of consumption of fluoroquinolones and macrolides have levelled off since 2005. Utilization rates for acute bronchitis are at the same level as when the program was first implemented, but rates for other acute upper respiratory tract infections of interest have declined. CONCLUSIONS: The Do Bugs Need Drugs? program significantly improves physician antibiotic prescription decisions and is ecologically associated with desirable change in population antibiotic consumption patterns.