Use of Admail and a geographic information system to send surveys to target populations.

INTRODUCTION: This paper briefly describes the use of Canada Post Unaddressed Admail and a geographic information system (GIS) for survey distribution to a specific target population in a large, sparsely populated geographic area, and the effectiveness of this approach. METHODS: Surveys were sent as Unaddressed Admail via Canada Post to a target population of people living within 5 km of a wind turbine in southwestern Ontario. RESULTS: The overall response rate from 8 wind farms (in 8 counties) was 8.1%. CONCLUSION: This approach has the potential to save time and money, but low response rates are common, distribution is not precise and there is potential for selection bias. Despite these flaws, Unaddressed Admail is worth consideration for delivery of information, study-recruitment materials and surveys to rural, remote and specific target populations.

INTRODUCTION: Nous décrivons brièvement l'utilisation du service Médiaposte sans adresse de Postes Canada et d'un système d'information géographique pour la distribution de sondages à une population cible précise sur un grand territoire peu densément peuplé, ainsi que l'efficacité de cette méthode d'envoi. METHODS: Nous avons utilisé le service Médiaposte sans adresse de Postes Canada pour envoyer des sondages à une population cible habitant dans le sud-ouest de l'Ontario à moins de 5 kilomètres d'une éolienne. RESULTS: Le taux de réponse global pour les 8 parcs éoliens visés (dans 8 comtés différents) était de 8,1 %. CONCLUSION: Bien que cette méthode puisse faire économiser temps et argent, elle n'engendre souvent qu'un faible taux de réponse, est imprécise sur le plan de la distribution et pourrait entraîner un biais de sélection. Malgré ces lacunes, le service Médiaposte sans adresse reste une option à envisager pour l'envoi de renseignements, de documents de recrutement en vue d'études et de sondages à des populations cibles précises vivant en milieu rural et éloigné.

Real-time surveillance for respiratory disease outbreaks, Ontario, Canada.

To validate the utility of a chief complaint-based emergency department surveillance system, we compared it with respiratory diagnostic data and calls to Telehealth Ontario about respiratory disease. This local syndromic surveillance system accurately monitored status of respiratory diseases in the community and contributed to early detection of respiratory disease outbreaks.

A descriptive analysis of hospitalization due to acute gastrointestinal illness in Canada, 1995-2004.

BACKGROUND: Gastrointestinal illness (GI) remains a leading cause of morbidity and mortality worldwide. In Canada, research has already demonstrated a rate in excess of one episode per person-year. National passive surveillance programs may be enhanced by information from hospitalizations for acute gastrointestinal disease. The objective of this report is to explore the incidence of acute GI in hospital administrative data collected by the Canadian Institute for Health Information (CIHI)--specifically the hospital morbidity database (HMDB). METHODS: Data from acute care facilities and select chronic care and rehabilitation facilities across Canada were analyzed using standardized rates, and age- and sex-adjusted rates for the years 1995-2004. RESULTS: The results indicate that GI causes at least 92,765 hospital admissions per year in Canada. In the majority (78.3%) of gastrointestinal hospitalizations, no specific etiology was recorded. Of the remaining diagnoses, 11.6% were due to viruses, 9.7% to bacteria and 0.3% to parasites. Age-standardized rates of hospitalizations for acute GI appear to have declined over the 10-year period. CONCLUSION: Gastrointestinal illness is still present in the Canadian population and presents a significant burden to the health care system. Whereas the HMDB likely underestimates the true rate of GI, it does capture cases that are serious enough to require hospitalization. This is a unique source of data and highlights other pathogen-specific disease data not currently collected through national surveillance tools (e.g., viruses).

Seroprevalence of Lawsonia intracellularis in different swine populations in 3 provinces in Canada.

Porcine proliferative enteropathy caused by Lawsonia intracellularis is an important enteric disease in swine throughout the world. Information regarding the distribution of this pathogen in Canadian swine herds would be beneficial for the creation of control protocols. Pigs from Ontario, Quebec, and Alberta were tested by using an indirect immunofluorescence assay for antibodies to L. intracellularis. Pig seroprevalence was calculated as the proportion of pigs positive from total pigs tested in the targeted population. Seroprevalence (+/- standard error [s(x)]) in market hogs in Ontario from farrow-finish (FF) farms and finishing (FIN) farms were significantly different at 77% (s(x) = 7%) and 29% (s(x) = 15%), respectively. Seroprevalence for sows and gilts in FF and farrowing and nursery (FAR + NUR) farms in Ontario were 90% (s(x) = 3%) and 93% (s(x) = 6%), respectively. Seroprevalence in breeding females in Quebec from FF and FAR farms was 82% (s(x) = 5%) and 87% (s(x) = 3%), respectively. Seroprevalence (57%, s(x) = 8%) in finishing pigs in Alberta from FF farms was significantly different from that of multisite (MS) farms and FIN farms, 6% (s(x) = 6%) and 9% (s(x) = 5%), respectively. Lawsonia intracellularis appears to be widespread in Canada and the seroprevalence on FF farms is higher than that on FIN and MS farms, possibly due to the presence of breeding females or management differences.

The risk of salmonellae shedding by dogs fed Salmonella-contaminated commercial raw food diets.

Twenty-eight research dogs were enrolled to determine the prevalence of salmonellae shedding after consumption of 1 Salmonella-contaminated commercial raw food diet meal. Sixteen dogs were exposed to Salmonella-contaminated commercial raw food diets and 12 to Salmonella-free commercial raw food diets. Seven of the exposed dogs shed salmonellae 1-7 days after consumption of Salmonella-contaminated raw food diets. None of the dogs fed Salmonella-free diets shed salmonellae. No clinical signs were observed in either group. Five of the 7 dogs shed the same serotypes as those recovered from food samples used for feeding. Results showed the same serotypes and antimicrobial resistance pattern in 2 of the 7 shedders. Dogs fed Salmonella-contaminated raw food diets can shed salmonellae and may, therefore, be a source of environmental contamination potentially leading to human or animal illness.

Contributing to communicable diseases intelligence management in Canada: CACMID meeting, March 2007, Halifax, Nova Scotia.

In the spring of 2003, the Public Health Agency of Canada (then, Health Canada) partnered with several provincial/territorial and regional public health stakeholders to improve pan-Canadian public health surveillance, communications and response through the application of new technologies. This resulted in the creation of the Canadian Network for Public Health Intelligence (CNPHI), a comprehensive framework of applications and resources designed to fill critical gaps in Canada's national public health infostructure. Over the past four years, the CNPHI has evolved into Canada's only pan-Canadian public health information management system. With over 2000 registered users, the current CNPHI environment consists of more than 30 integrated applications and systems that can be loosely categorized into four functional groups: data exchange; data analysis and integration; communication, collaboration and coordination; and knowledge management. Despite poor data repositories, legacy information management systems, and the lack of standards and agreements, the CNPHI has demonstrated that much can be accomplished in these areas. Over the next decade, significant barriers impeding additional advances will be bridged through the implementation of the Electronic Health Record, and through ongoing efforts to address gaps in standards, and data- and information-sharing agreements. Together with new technologies coming on-line, opportunities to further enhance public health surveillance and response will be limited only by one's imagination.

In vivo efficacy study of the anti-inflammatory properties of Surolan.

This study evaluated the anti-inflammatory properties of Surolan with the use of a pinna model of inflammation in 80 mice and a randomized complete block design. Within each of 8 blocks, 10 treatments, consisting of different combinations of the constituents of Surolan with and without the prednisolone acetate component, were randomly assigned to the 9-wk-old CD-1 mice. The treatments were administered as a single dose 30 min after pinna inflammation was induced with tetradecanoylphorbol acetate. Ear-skin edema and erythema were assessed and measured 4 and 6 h thereafter. Treatment effects were evaluated with repeated-measures analysis of variance. Inclusion of prednisolone acetate with the Surolan vehicle, either alone or in combination with the nonsteroidal constituents of the suspension, resulted in a significant reduction in mean ear-skin thickness and erythema. The inflammation-reducing properties of prednisolone were not significantly affected by the other components of Surolan.

A GIS-driven integrated real-time surveillance pilot system for national West Nile virus dead bird surveillance in Canada.

BACKGROUND: An extensive West Nile virus surveillance program of dead birds, mosquitoes, horses, and human infection has been launched as a result of West Nile virus first being reported in Canada in 2001. Some desktop and web GIS have been applied to West Nile virus dead bird surveillance. There have been urgent needs for a comprehensive GIS services and real-time surveillance. RESULTS: A pilot system was developed to integrate real-time surveillance, real-time GIS, and Open GIS technology in order to enhance West Nile virus dead bird surveillance in Canada. Driven and linked by the newly developed real-time web GIS technology, this integrated real-time surveillance system includes conventional real-time web-based surveillance components, integrated real-time GIS components, and integrated Open GIS components. The pilot system identified the major GIS functions and capacities that may be important to public health surveillance. The six web GIS clients provide a wide range of GIS tools for public health surveillance. The pilot system has been serving Canadian national West Nile virus dead bird surveillance since 2005 and is adaptable to serve other disease surveillance. CONCLUSION: This pilot system has streamlined, enriched and enhanced national West Nile virus dead bird surveillance in Canada, improved productivity, and reduced operation cost. Its real-time GIS technology, static map technology, WMS integration, and its integration with non-GIS real-time surveillance system made this pilot system unique in surveillance and public health GIS.

Pneumococcal conjugate vaccination in Canadian infants and children younger than five years of age: Recommendations and expected benefits.

INTRODUCTION: Streptococcus pneumoniae infection may result in invasive pneumococcal disease (IPD), such as bacteremia, meningitis and bacteremic pneumonia, or in non-IPD, such as pneumonia, sinusitis and otitis media. In June 2001, a heptavalent pneumococcal conjugate vaccine (PCV7) (Prevnar, Wyeth Pharmaceuticals, Canada) was approved for use in children in Canada. The objective of the present paper is to review S pneumoniae-induced disease incidence and vaccine recommendations in Canadian infants and children younger than five years of age. Particular attention is given to the expected benefits of vaccination in Canada based on postmarketing data and economic modelling. METHODS: Searches were performed on PubMed and Web of Science databases and specific Canadian journals using the key words 'pneumococc*', 'vaccine', 'conjugate', 'infant' and 'Canadian'. RESULTS AND DISCUSSION: PCV7 appears to be safe and effective against IPD and non-IPD in children younger than five years of age and, more importantly, in children younger than two years of age (who are at highest risk for IPD). An examination of postmarketing data showed a reduction in incidence of pneumococcal disease in age groups that were vaccinated and in older age groups, indicating the likelihood of herd protection. Concurrently, there was a reduction in the occurrence of antimicrobial-resistant isolates. CONCLUSIONS: The results from the present review suggest that PCV7 is currently benefiting Canadian children and society by lowering S pneumoniae-associated disease. Additional gains from herd protection and further reductions in antimicrobial resistance will be achieved as more Canadian children younger than five years of age are routinely vaccinated with PCV7.

Milk residues and performance of lactating dairy cows administered high doses of monensin.

Milk residues and performance were evaluated in lactating cows that were fed up to 10 times the recommended dose of monensin. Following an acclimatization period of 14 d, during which cows were fed a standard lactating cow total mixed ration containing 24 ppm monensin, 18 lactating Holstein dairy cows were grouped according to the level of feed intake and then randomly assigned within each group to 1 of 3 challenge rations delivering 72, 144, and 240 ppm monensin. Outcome measurements included individual cow daily feed intakes, daily milk production, body weights, and monensin residues in composite milk samples from each cow. There were no detectable monensin residues (< 0.005 microg/mL) in any of the milk samples collected. Lactating cows receiving a dose of 72 ppm monensin exhibited up to a 20% reduction in dry matter intake, and a 5% to 15% drop in milk production from the pre-challenge period. Cows receiving doses of 144 and 240 ppm monensin exhibited rapid decreases in feed intake of up to 50% by the 2nd d and milk production losses of up to 20% and 30%, respectively, within 4 d. Lactating cows receiving up to 4865 mg monensin per day had no detectable monensin residues (< 0.005 microg/mL) in any of the milk samples collected. Results of this study confirm that food products derived from lactating dairy cattle receiving monensin at recommended levels are safe for human consumption.

Infectious disease outbreaks related to drinking water in Canada, 1974-2001.

BACKGROUND: Recent public attention on drinking water supplies in the aftermath of waterborne infection outbreaks in Walkerton and North Battleford raises questions about safety. We analyzed information on waterborne outbreaks occurring between 1974 and 2001 in order to identify apparent trends, review the current status of monitoring and reporting, and gain a better understanding of the impact of drinking water quality on public health and disease burden. METHODS: Data from outbreak investigations, published and unpublished, were categorized by the type of drinking water provider and were assessed to be definitely, probably or possibly waterborne in nature. RESULTS: The final data set consisted of 288 outbreaks of disease linked to a drinking water source. There were 99 outbreaks in public water systems, 138 outbreaks in semi-public systems and 51 outbreaks in private systems. The main known causative agents of waterborne disease outbreaks were (in descending frequency of occurrence) Giardia, Campylobacter, Cryptosporidium, Norwalk-like viruses, Salmonella and hepatitis A virus. SUMMARY: We found that severe weather, close proximity to animal populations, treatment system malfunctions, poor maintenance and treatment practices were associated with the reported disease outbreaks resulting from drinking water supplies. However, issues related to the accuracy, co-ordination, compatibility and detail of data exist. A systematic and coordinated national surveillance system for comparison purposes, trend identification and policy development is needed so that future waterborne disease outbreaks can be avoided.

Syndromic surveillance of gastrointestinal illness using pharmacy over-the-counter sales. A retrospective study of waterborne outbreaks in Saskatchewan and Ontario.

OBJECTIVE: To ascertain if monitoring over-the-counter (OTC) drug sales could provide a timely syndromic surveillance method of detecting outbreaks of gastrointestinal illness. METHOD: This study evaluated the potential of a syndromic surveillance system by comparing retrospective pharmacy OTC sales of anti-nauseants and anti-diarrheals to emergency room visits and case numbers from two Canadian outbreaks related to water contamination by Cryptosporidium, and E.coli O157:H7 and Campylobacter. RESULTS: Local sales trends of weekly aggregate OTC products were comparable to the outbreak epidemic curves. Statistical control tests on the sales data indicated the start of the outbreak periods. CONCLUSIONS: An automated monitoring tool based on spatial and temporal trend analyses of daily OTC sales would provide supplemental community health information for public health officials that is timelier than currently available laboratory-based surveillance systems.

Frozen chicken nuggets and strips--a newly identified risk factor for Salmonella Heidelberg infection in British Columbia, Canada.

Salmonella enterica var. Heidelberg was isolated from an unusual food source during routine case follow-up, prompting a case control investigation of frozen chicken nuggets and strips. Most frozen nuggets and strips are raw; however, par-frying lends a cooked appearance. As such, suitable food preparation precautions might not be undertaken by consumers. Cases were confirmed in the laboratory between 1 January and 1 April 2003. Controls were generated through forward-digit dialing and individually matched by age category. Telephone interviews were conducted, and limited sampling of unopened product was performed. Eighteen matched pairs were interviewed. The odds of infection were 11 times higher in individuals who had consumed frozen processed chicken nuggets and strips (95% confidence interval, 1.42 < odds ratio < 85.20). One-third of cases and controls considered frozen nuggets and strips to be precooked, and one quarter used the microwave, an ill-advised cooking method. Consumer misconceptions contributed to the risk of infection. Clear labels identifying nuggets and strips as raw poultry are needed.

The status of drinking water in Ontario, Canada (1992-1999).

OBJECTIVE: This study was conducted to investigate the characteristics of public water works (PWW) in southern Ontario with respect to their water sources and treatment regimes. METHODS: Data from 481 PWW covering the period 1992-1999 were collected and cartographic manipulations as well as descriptive analyses of the PWW attributes were performed. Tests of associations between different PWW attributes were done using Fisher's Exact test and Cochran-Mantel-Haenszel statistics. RESULTS: Water sources for the PWW included surface water (SW) (21% lakes; 13% rivers), ground water (GW) (64%) and mixed sources (2%). Most (81%) of the population was supplied with SW. Filtration was performed by 84% and 8% of the PWW using SW and GW, respectively. Similarly, disinfection was performed by 99% and 91% of the PWW using SW and GW respectively. There was no significant difference in treatment regimes between PWW in urban and those in rural areas but treatment regime was a function of water source. Overall, most PWW (87.8%) met the minimum treatment requirements of the then Ontario Drinking Water Objectives (ODWO). DISCUSSION: The study shows that most PWW complied with the minimum treatment requirements of the then ODWO. The minimum treatment required by the ODWO was disinfection for GW and both disinfection and filtration for SW. The non-compliant PWW will need to comply for continued provision of safe drinking water. Suffice it to say that both watershed protection and improved water treatment will be imperative for the continued provision of safe drinking water and control of waterborne diseases.