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The information presented here reflects the activities of those organizations and agencies with the most impact on infection control in Canada. There are, however, numerous other organizations both on a national and provincial level that also play important roles in infection control. Although great strides have been made in infection control in Canada, we still have much to do to raise the profile of this important activity.
We report the results of a comparison of the dosimetric standards of Canada and France for photon beams at 60Co and a few higher energies. The present primary standard of absorbed dose to water for NRC, Canada is based on measurements made with a sealed water calorimeter. The corresponding standard of the LNHB, France is based on measurements made with a graphite calorimeter at 60Co energy and transferred to absorbed dose to water for 60Co and higher-energy photon beams using both ion chambers and Fricke dosemeters as transfer instruments. To make this comparison, we used three graphite-walled NE2571 Farmer chambers. The absorbed dose to water determined by the LNHB was greater than that determined by NRC by 0.20% at 60Co energy. This difference is not significant given the uncertainties on the standards. In order to do the comparison for higher-energy photons, we interpolated the NRC data set at the beam qualities used at the LNHB. When %dd(10)x is used as the method of specifying beam quality, the determination of absorbed dose to water by the LNHB is about 0.2% greater than that determined by NRC and consistent with the results at 60Co. However, when using TPR20,10 as the beam quality specifier, the LNHB determination is greater than the NRC's determination by 0.8% and 1.2% at 12 and 20 MV respectively. This discrepancy, which systematically increases with increasing energy, eventually exceeds the uncertainties in the ratio of the standards, estimated to be 0.7%. This underscores the importance of selecting the method of specifying beam quality, either %dd(10)x or TPR20,10, at least for the 'soft' beams used by NRC in this comparison. In the case of the air kerma standards, which were also compared at 60Co energy, the LNHB determination was greater than NRC's by 0.14%, which is not significant given the uncertainties on the standards.
Most circulating 25-hydroxyvitamin D originates from exposure to sunlight; nevertheless, many factors can impair this process, necessitating periodic reliance on dietary sources to maintain adequate serum concentrations. The US and Canadian populations are largely dependent on fortified foods and dietary supplements to meet these needs, because foods naturally rich in vitamin D are limited. Fluid milk and breakfast cereals are the predominant vehicles for vitamin D in the United States, whereas Canada fortifies fluid milk and margarine. Reports of a high prevalence of hypovitaminosis D and its association with increased risks of chronic diseases have raised concerns regarding the adequacy of current intake levels and the safest and most effective way to increase vitamin D intake in the general population and in vulnerable groups. The usual daily intakes of vitamin D from food alone and from food and supplements combined, as estimated from the US third National Health and Nutrition Examination Survey, 1988-1994, show median values above the adequate intake of 5 microg/d for children 6-11 y of age; however, median intakes are generally below the adequate intake for female subjects > 12 y of age and men > 50 y. In Canada, there are no national survey data for estimation of intake. Cross-sectional studies suggest that current US/Canadian fortification practices are not effective in preventing hypovitaminosis D, particularly among vulnerable populations during the winter, whereas supplement use shows more promise. Recent prospective intervention studies with higher vitamin D concentrations provided evidence of safety and efficacy for fortification of specific foods and use of supplements.
A written survey of all licensed medical laboratories performing coagulation testing in Canada was undertaken in 1996 as a follow-up to a study performed in 1992. The an overall response rate was 77.4% of the laboratories surveyed. During the 4-year period between surveys, the percentage of responding laboratories using some format for international normalized ratio (INR) reporting increased from 57% to 98%. The mean International Sensitivity Index (ISI) of the various thromboplastins used had decreased from 2.07 to 1.63. However, only 35% of responding laboratories used a thromboplastin with an ISI of 1.2 or less as recommended by the American College of Chest Physicians. In 92% of cases, the ISI was said to be specified for the type of instrument, ie, optical density vs mechanical. However, in only 52% of cases was the ISI known to be specific for the particular reagent-analyzer combination used in the individual laboratory. Nine percent of the laboratories were still using an inappropriate denominator for the INR calculation. While 87% of laboratories quoted a therapeutic INR range of 2.0 to 3.0 for venous thromboembolism, there was much greater variation in the range reported for patients undergoing heart valve replacement. The situation in Canada has improved in using the INR system for prothrombin time reporting. However, additional education is required, as is greater use of thromboplastins with a lower ISI.
Investigations on the use of poliovirus vaccines in the Caribbean and Canada are reviewed. Studies in Trinidad and Tobago in 1963 showed that children who were given two doses of oral poliovirus vaccine responded satisfactorily to the type 2 and type 3 components but poorly to the type 1 component. Studies on poliovirus vaccines in Canada have indicated that both killed and live vaccines are capable of controlling poliomyelitis. Results of studies undertaken in Ontario suggested that the response to a killed vaccine was not entirely satisfactory. The need for continued surveillance for poliomyelitis is emphasized. Action should be taken to review immunization procedures when a single case occurs. Consideration should be given to the use of monovalent vaccines in tropical countries.
Using data from the Survey of Old Age Security and Canadian Pension Plan Retirement Recipients conducted by Health and Welfare Canada in 1987, this article estimates the relationship between sociodemographic characteristics and institutionalization of elderly persons in Canada. Region of residence was introduced in our model as a proxy for system effects. Logistic regression showed that age, marital status, health, family income, and region of residence all have a significant effect on institutionalization. We look at policies specific to different provinces to elaborate some hypotheses on how they affect the likelihood of residing in an institution. When trying to estimate the future needs and costs of institutional housing, this study shows the importance of considering not only the number of persons aged 65 years and over, but also expected changes in their sociodemographic characteristics and in the policies concerning long-term care services.
Given the distinctive historical experiences, cultural features, and status positions of the diverse ethnic groups in Canadian society, we anticipate that these differences will influence the retirement behavior and conditions of their members. This paper examines the effects of ethnic group membership for immigrants to Canada on the timing of retirement and the sources and amounts of retirement income using data from the Public Use Sample of the 1981 Census of Canada. Separate but parallel analyses are conducted for men and women to take into account their distinctive labor force experiences. We find that membership in Asian, African, or Latin American ethnic groups is associated with both later retirement and a lower probability of receiving social insurance and private pension benefits, as well as appreciably lower income among elderly men. This is likely the result of changes in pension legislation in the 1960s and 1970s reducing benefits to recent immigrants.
BACKGROUND: End-stage renal disease (ESRD) incidence and prevalence are increasing in many countries worldwide. Due to the high cost of therapy, predicting future numbers of patients requiring dialysis and transplantation is necessary for health care planners. Projecting therapy-specific chronic disease prevalence is inherently problematic, and examples of suitable models and their application are sparse. When applied, rarely was the adequacy of such models evaluated. METHODS: We describe and illustrate a method for projecting therapy-specific ESRD prevalence in Canada for 1995-2005 using data obtained from the Canadian Organ Replacement Register. The projections combine the Poisson model for incidence rates and a Markov model for patient follow-up. Model adequacy is empirically validated by data-splitting. RESULTS: Large increases in ESRD prevalence are expected in Canada, with an average annual increase of 6.9% projected for 1995-2005. Upon validation, the projection model based on 1981-1987 data was able to predict 1994 prevalence within 1%, while projected therapy-specific prevalences closely approximated those observed. CONCLUSIONS: Therapy-specific ESRD prevalence was successfully projected using Poisson and Markov models. Where multistate prevalence forecasts are required, the method could be augmented for application to various other chronic diseases.
Discussions of quality assurance mechanisms for health professions are increasing in Canada. In their roles of protecting the public from incompetent or unsafe health care, and enhancing the quality of care provided by practitioners, provincial licensing organizations are taking an interest in quality assurance programmes. The paper reports the results from a national survey of five self-regulating health professions (dentistry, medicine, nursing, optometry and pharmacy) in Canada. The study found two types of activities in place--a complaints programme and a routine audit programme. Both programmes use a similar approach to identifying poor performers within a health profession. The paper discusses the results of the study, the advantages and disadvantages of the approach used, and suggests a second approach to quality assurance which could be used in conjunction with current activities.
OBJECTIVES: To investigate the nature of the amino acid motifs found in penicillin-binding protein (PBP) 2b and PBP1a of penicillin-resistant Streptococcus pneumoniae isolates across Quebec (Canada), and to obtain preliminary information regarding the prevalence of these alterations. METHODS: DNA sequences of pbp2b (codons 210-675) and pbp1a (codons 310-682) transpeptidase domains were determined and compared in 48 clinical isolates comprising 17 penicillin-susceptible (PSSP), 19 penicillin-intermediate (PISP) and 12 penicillin-resistant (PRSP) pneumococci. RESULTS: The degree of diversity within PBP1a and PBP2b correlated with increased resistance to beta-lactam antibiotics. There were an average of 0.6 +/- 0.4 and 2.9 +/- 0.2 mutations in PSSP, 16.8 +/- 1.4 and 36.3 +/- 5.2 in PISP, and 18.7 +/- 2.5 and 51.4 +/- 1.3 in PRSP isolates compared with control penicillin-susceptible R6-PBP2b and R6-PBP1a sequences, respectively. At least seven PBP2b and six PBP1a distinct amino acid profiles were identified among intermediate or resistant strains isolated in Quebec. The pattern of distribution of the PBPs' altered amino acids differs from that of other countries, with pneumococci isolates from Quebec showing a unique genetic signature. CONCLUSION: This study will serve as a basis for future monitoring of genetic changes associated with the emergence and spread of beta-lactam resistance in Quebec, Canada.
Infection with the hepatitis C virus (HCV) is a major public health burden in Canada and globally. The literature shows that injection drug use is currently the primary transmission route for HCV, and that a majority of injection drug users (IDUs) are currently infected with HCV in Canada. This article first reviews the burden of HCV within IDU populations and the transmission risks and the treatment implications specific to IDUs. Traditionally, IDUs have been excluded from HCV treatment unless abstaining from illicit drug use. However, recent research suggests that categorical exclusion is not medically necessary. A series of key questions about the feasibility of offering HCV treatment to IDUs in the specific Canadian context are considered, including concerns related to the motivation of treatment for IDUs, treatment delivery, treatment side effects, HCV reinfection, and the social environment. The article concludes that treatment of HCV-infected illicit drug users is both feasible and may be necessary to reduce transmission and adverse outcomes in this high-risk population.
BACKGROUND: Only unbiased estimates of end-stage renal disease (ESRD) incidence and trends are useful for disease control-identification of risk factors and measuring the effect of intervention. METHODS: Age- and sex-standardized incidences (with trends) were calculated for all-cause and diabetic/non-diabetic ESRD for persons aged 0-14, 15-29, 30-44 and 45-64 years in 13 populations identified geographically, and six populations identified by ethnicity. RESULTS: The incidence of ESRD varied most with age, ethnicity and prevalence of diabetes. All non-Europid populations had excess ESRD, chiefly due to rates of type 2 diabetic ESRD that were greater than accounted for by community prevalences of diabetes. Their rates of non-diabetic ESRD also were raised, with contributions from most common primary renal diseases except type 1 diabetic nephropathy and polycystic kidney disease. The ESRD rates generally were low, and more similar than different, in Europid populations, except for variable contributions from type 1 (high in Finland, Sweden, Denmark and Canada) and type 2 (high in Austria and Canada) diabetes. In Europid populations during 1998-2002, all-cause ESRD declined by 2% per year in persons aged 0-44 years, and all non-diabetic ESRD by a similar amount in persons aged 45-64 years, in whom diabetic ESRD had increased by 3% per year. CONCLUSIONS: Increased susceptibility to type 2 diabetes and to kidney disease progression characterizes excess ESRD in non-Europid peoples. The decline in all-cause ESRD in young persons, and non-diabetic ESRD in the middle-aged, probably reflects improving management of progressive renal disease.
Appendicitis is more common in developed than in developing societies and appendiceal fecaliths are thought to have an etiologic role in the disease. The geographic distribution of appendiceal fecaliths was investigated by systematic, intraoperative palpation of the appendix in patients in Toronto, Canada and Johannesburg, South Africa. The incidences of fecaliths found on pathologic sectioning of the appendix in appendicitis patients in both societies were compared. In the Canadian population, the prevalence of fecaliths in patients whose appendices were palpated incidentally was 32% versus 52% for those with appendicitis (p less than 0.01). In the African population, the prevalence of fecaliths in patients whose appendices were palpated incidentally was four per cent versus 23% for those with appendicitis (p = 0.04). The difference in prevalence of incidental appendiceal fecaliths in the two populations was statistically significant (p less than 0.005). The prevalence of fecaliths is higher in developed countries, such as Canada, than in developing countries, such as Africa, and is also higher in patients with than in those without appendicitis. These data support the theory that the low-fiber diets consumed in developed countries lead to fecalith formation, which then predisposes to appendicitis.
The Canadian Supreme Court will soon make a decision about Harvard University's long-standing application for a Canadian patent on a mouse transgenic for the myc oncogene. That decision could reignite in North America the controversy that continues in Europe and elsewhere to surround the patenting of life forms. The tortuous steps in this 15-year patent maze are marked by the arguments about life patents that attended the U.S. Supreme Court's decision in Diamond v. Chakrabarty. This patent dispute about oil-digesting bacteria cracked open the door for animal patents in the United States and other countries, even though the legal arguments involved were based on patent applications for corn seeds and oysters, not mammals. The patent challenge to the Harvard mouse by the Canadian government now threatens to close this door in Canada. The arguments against life patents are commonly based on moral and religious grounds that regard the sanctity of life and oppose its commodification. The most compelling arguments for such patents are based on the benefits they deliver through commercial exploitation of inventions. The debate about patenting animals has been more heated outside North America and cacaphonic in the Third World. However, the Canadian debate could be amplified by the U.S. Supreme Court's recent entry on the biopatent stage through the side door of a new corn seed patent dispute. A narrow legal analysis by the Canadian Supreme Court would award the mouse patent to Harvard, while a policy analysis might support the government's challenge of the patent. Although the impact of the Harvard mouse patent process in Canada could be just a squeak, opponents of patenting life can mount the myc mouse to once again roar their opposition to animal patents. And the sound could resonate through the arguments about both biopatents and human cloning, with potentially important effects for academia, industry, and the public.
The authors set out to review Canadian medical workforce policies for 1993 to 2003 and assess if data existed in the 1990s that could have reversed the policy decision to curtail the supply of physicians from Canada's medical schools just as Canada was about to experience a developing shortage. The authors reviewed existing descriptive data sources regarding Canadian physician workforce size and activity from 1986 to 2003, including the Canadian Medical Association workforce database. The review indicated that a significant loss of physicians to retirement was imminent. Physician workforce productivity had started to fall by the early 1990s. Emigration to the United States had risen above traditional levels in the early 1990s and remained higher into the late 1990s. Despite these existing findings, an integrated adjustment to physician workforce policies taken in 1993-94 only occurred after 1999. The authors recommend that policy makers and managers must monitor the numbers from existing sources. To optimize these sources, planned data tracking and linkages are essential. The period in question demonstrated major disconnects in coordinating implementation, wherein subject experts monitoring data trends were not adequately utilized by policy makers. Finally, in complex systems with regional differences, policy decisions based on normative data are insufficient.
Enhancement of comparative ambulatory care information reporting systems will expand the ability of health care managers to assess accurately the opportunities and relative benefits and costs of substituting ambulatory care for traditional inpatient services without jeopardizing the five basic principles of Canada's health care system: universality, accessibility, portability, comprehensiveness, and public administration. In the long run, this will improve Canada's ability to provide high-quality and cost-effective health care within the constrained resources now available.
As a companion article to the Journal of Clinical Engineering's series on Bioengineering Education in the United States, this paper describes the biomedical engineering and biomedical engineering technology programs in Canada. The purpose of the article is not to evaluate each program, but to illustrate the breadth of bioengineering and related programs available today in this country. While biomedical engineering technology programs are offered at the college level, the Canadian philosophy toward biomedical engineering is slightly different from that found in the United States: in Canada, biomedical engineering is offered only at the graduate level to qualified applicants with a previous degree in engineering, science, medicine, or dentistry.
This paper updates the information contained in a previously published paper, ¿Bioengineering Education in Canada, 1988,¿ which appeared in the Journal of Clinical Engineering (Volume 13, No. 5). It describes the current biomedical engineering and biomedical engineering technology programs available in Canada, but does not attempt to evaluate them. There are no undergraduate degree programs specifically in biomedical engineering, although three universities have created options in biomedical engineering in undergraduate programs. Also, the clinical engineering program at the University of British Columbia has been discontinued.