Projections of Graduates from Canadian Medical Schools, 1970-81

This paper sets forth the projections made by the various Canadian medical schools of first-year undergraduate enrolment through 1977-78. Non-Canadian enrolment and student attrition are discussed and some assumptions are made concerning their levels up to 1981. In conclusion, a set of projections on Canadian and landed immigrant graduates from Canadian medical schools during the period 1970-1981 is offered. The national projections are broken down by medical school and province.The results of this paper indicate that Canadian medical schools will graduate 1019 Canadians and landed immigrants in 1970, 1052 in 1971, 1064 in 1972, 1113 in 1973, 1250 in 1974, 1342 in 1975, 1377 in 1976 and 1480 in 1981.     

Birth prevalence and recurrence rates of neural tube defects in southern Alberta in 1970-81.

Given the observed variation in birth prevalence and recurrence rates of neural tube defects, it is important to obtain such data specific to a given locality for research and genetic counseling purposes. A review of hospital medical charts, the patient lists of the Medical Genetics and Myelomeningocele clinics at Alberta Children''s Hospital and data from the Canadian Congenital Anomalies Surveillance System revealed the annual birth prevalence rate of neural tube defects in southern Alberta in 1970-81 to be 1.62/1000 total births. This figure suggests southern Alberta to be a low-frequency area. There was no significant variation in the annual rates of spina bifida, encephalocele or all neural tube defects combined over the study period. A significant linear decline in the frequency of births of anencephalic infants, however, was noted (p = 0.025). Information on the total reproductive history of the mothers revealed that the empiric risk of recurrence of a neural tube defect was 2.2%, and the risk to all siblings was estimated to be 2.3%. In future prevalence studies multiple sources of case ascertainment should be used, including data on pregnancies terminated because of a fetal neural tube defect.     

Violent and accidental mortality among four immigrant groups in Canada, 1970-1972.

For most people immigration to a new country such as Canada entails a positive move and an improvement in life. The many challenges associated with resettlement may, however, lead to insurmountable difficulties, stresses and conflict for a significant number of newcomers. The mortality experience of immigrants, as reflected in cause-of-death statistics, may provide indication of the extent of stress and conflict in their migration experience. This situation is most clearly exhibited in mortality from suicide, homicide, and motor vehicle accidents. In this study, hypotheses concerning immigrant mortality in Canada are developed and tested with a log-linear model for rates pertaining to rare events. Overall, the results give support for the importance of country-of-origin effects in explaining suicide propensities, but not for homicide and motor vehicle accidents mortality. Income discrepancies are a significant determinant of variability in death rates overall, but discrepancies between the immigrants in this study and the Canadian-born are not of much significance. The strongest net effect on the cause-specific death rate is associated with group membership. This effect likely reflects a number of residual unmeasured sources of variation including the influence of the immigrant ethnic community as a source of social support, and the potential confounding effects of migration selectivity.     

Isolation and geographic distribution of Mycobacterium other than M. tuberculosis in British Columbia, 1972-81

It has been suggested that the incidence of infection with mycobacteria other than typical tubercle (MOTT) bacilli is increasing. Laboratory and epidemiologic information relating to MOTT infection in British Columbia between 1972 and 1981 was analysed. Patient records for 1960-81 were also analysed. Of the 313 661 laboratory specimens 13 474 yielded Mycobacterium tuberculosis isolates and 3172, MOTT isolates. Over the 10 years the number of M. tuberculosis isolates declined, whereas the absolute and relative numbers of MOTT isolates increased. Members of the highly drug-resistant MAIS complex (M. avium-intracellulare, M. scrofulaceum and M. simiae) accounted for 73.3% of the 1778 potentially pathogenic MOTT isolates. MAIS isolation rates varied geographically. Analysis of patient records revealed 217 MOTT infections, of which 152 (70%) were due to MAIS organisms. Further studies are needed to determine the source of MAIS organisms in order that the infection and the disease may be more clearly understood.     

Active tuberculosis in Indochinese refugees in British Columbia.

The incidence of active tuberculosis in 8692 Indochinese refugees admitted to British Columbia between 1979 and 1981 was reviewed. In the first 3 months after entry into the province the rate was extremely high--estimated at 1890/100 000 (126 times the provincial average). A large proportion of these cases were of primary or minimal pulmonary tuberculosis. However, although the proportion of cases of minimal pulmonary tuberculosis was twice the provincial average, the proportion of these cases that were confirmed by culture was only one third the provincial average; this suggests some overdiagnosis in this period. In the subsequent 21 months of residence the incidence of active tuberculosis was also high, at 353/100 000, which was more than 20 times the provincial average. The distribution of cases by severity was closer to the provincial distribution in this period, but advanced disease accounted for a far smaller proportion of cases in both periods than it did in 1980 in the entire province.     

The epidemic spread of Salmonella typhimurium phage type 10 in Canada (1970-1979)

The frequency of Salmonella typhimurium phage type 10 across Canada was monitored during the period 1970-1979. Phage type 10 isolations increased from 1.2% in 1970 to 68.8% in 1979 among isolates from human sources and from 1.5 to 30.6% in isolates from nonhuman sources. Examination of food-poisoning outbreaks and a study of the animal-host associations of phage type 10 revealed that contaminated poultry products appear to be the most common sources of human infections. The majority (89.3%) of S. typhimurium phage type 10 strains were sensitive to antibiotics. Of the resistant strains, 73.3% were resistant to single antibiotics and 26.7% were multiresistant. Thirty-three different patterns of antibiotic resistance were observed. A number of the resistance determinants were transferable by conjugation and the R plasmids were found to belong to the incompatibility groups HI1, FII, N, I alpha, and C.     

Active observation in management of acute abdominal pain in childhood.

Out of 363 children admitted to a surgical unit with acute abdominal pain only 126 (35%) had an operation. Of these, 20 first underwent a period of "active observation." This procedure, used to help reach a diagnosis or decision in doubtful cases, is safe and useful and may be applied at home or in hospital.     

Incidence of active tuberculosis in the native population of Canada.

We analysed the incidence rates of active tuberculosis reported between 1970 and 1981 in three groups of people born in Canada: Inuit, registered Indians and others (mainly of European origin). While the rates of tuberculosis were quite low in the last group, which constitutes about 82% of the population of Canada, they were 16 times higher among Indians and 24 times higher among Inuit. Some 20 to 30 years ago the Inuit had the highest recorded rate of tuberculosis in the world; with an intensive program the rate decreased sharply. Such a program has not been implemented among the Indian population, and the incidence rate has not decreased as rapidly. A major effort is required to satisfactorily control tuberculosis among Indians. In addition, we must not allow our efforts to slacken in the control of tuberculosis among the Inuit.     

Chickenpox in Canada, 1924-87.

Because of the lack of an effective vaccine and the difficulty in implementing any effective control measures, physicians and public health practitioners have paid little attention to understanding the epidemiologic features of chickenpox. No data on the incidence rate in Canada are available for 1959-85. However, Ontario data suggest an overall decrease in the annual rate during the 1960s and a stable rate since the mid-1970s. High incidence rates are expected among children 5 to 9 years of age because of their susceptibility and their greater exposure in school. Low incidence rates among older age groups are expected, because most of these people have already been exposed to the virus. The disease is more serious among infants than among other children. The risk of death from chickenpox is also highest among infants. More patient-specific information and improved collection of incidence data are required to measure any impact from future control procedures, including the use of vaccines currently being developed.