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Staff from 3 Toronto hospitals were surveyed for knowledge, attitudes and concerns about AIDS. 70% of the 1,366 respondents had direct clinical experience with persons with AIDS. Data were analyzed according to hospital setting and professional group: physicians, nurses, technologists and supervisory staff. No setting difference was observed and although statistically significant differences (at the .001 level) were observed between professional groups, these differences are small and have little practical importance. In general, subjects answered 68% of the knowledge questions correctly. All attitudes and concerns were inversely associated to knowledge (Pearson r range was -.31 to -.20). Multivariate analysis demonstrated that knowledge and concern about contagion are important mediating variables (multiple r = .40) for other attitudes and concerns.

We describe the sexual behaviour reported by 240 seronegative and seropositive homosexual men over a 3-year period. Sexual partners of men with HIV disease were recruited into a prospective study between July 1984 and July 1985 and were monitored every 3 months thereafter. Data on sexual activities were collected through interviewer-administered questionnaires. The cohort experienced a reduction in both the number of sexual partners and the volume of sexual activity. Reductions in the number of partners were early and dramatic. Changes in sexual activities were gradual and consistent in trend. The greatest reduction occurred in high risk activities (receptive and insertive anal intercourse). After 3 years of follow-up, only 10% of the men continue to be exposed to semen through unprotected receptive anal intercourse and 18% through unprotected receptive oral-genital sex. The proportion of men engaging in oral-genital contact and masturbation remained stable over the 3 years. Once informed of their serostatus, both seropositive and seronegative men reduced their high risk behaviour. The decline in rates of STDs and seroconversion confirmed that this cohort had indeed reduced their high risk behaviour.

Testing saliva for the detection of human immunodeficiency virus (HIV) antibodies has many potential advantages for epidemiologic surveillance. A commercial ELISA kit and a standardized in-house immunoblot (IB) system were slightly modified to enhance antibody detection in saliva. Frozen saliva specimens from Toronto Sexual Contact Study participants (including sequential saliva specimens collected during seroconversion) were tested as were fresh saliva samples collected from a population of street-based intravenous drug users (IVDUs). HIV antibody results on saliva were compared with HIV serostatus determined by ELISA and IB on serum or dried blood spots. The overall sensitivity was 98.3% (117/119) for the kit and 99.2% (118/119) for IB; the specificity was 100% (429/429). In the IVDU population, compliance in the voluntary submission of specimens increased from 69% agreeing to provide blood samples to 89% agreeing to provide blood, saliva, or both. Saliva specimens can be easily collected under difficult field conditions with minimal training and provide a valuable alternative to testing blood for HIV-seroprevalence studies.

HIV antigen detection kits are available from a number of commercial sources. Abbott, Coulter, and Du Pont antigen kits were used to test 661 sera collected sequentially from 65 members of the Toronto Sexual Contact Study (TSCS). The sera had been collected at 3-month intervals over 4 years from nine persistently HIV-seronegative men, 14 seroconverters, and 42 seroprevalent participants. Antigen was not detected in any seronegative men. Two of 14 seroconverters were antigen positive in the specimen immediately preceding seroconversion (by all kits). Antigen was detected in 22 of 56 seropositive participants; of these, 16 of 22 demonstrated the emergence of antigen during observation. Discrepancies were noted in the time of detection of antigen (ranging from 3 months to more than 3 years) in nine participants. Although overall concordance among all kits for all specimens appears high (95.4%), when the bias introduced by testing multiple specimens from the same patient is removed, the lower bound of concordance among all three kits is estimated to be 80%. Similarly, after correction, the upper and lower bound of estimates of sensitivity are Abbott 96, 92%; Coulter 88, 63%; and Du Pont 88, 58%. There are significant differences in the performance characteristics of these commercial products for the detection of HIV antigen in serum.

Eight hundred volunteers from heath care and emergency fields participated in a randomized double-blind clinical trial of a new experimental mammalian cell-derived recombinant DNA hepatitis B vaccine (Betagen) compared with a licensed plasma-derived vaccine (Heptavax-B). Vaccine injections (20 micrograms) were administered intramuscularly at 0, 1, and 6 months, and sera were tested at 0, 1, 2, 3, 6, 7, and 12 months for hepatitis B surface antigen, antibody to hepatitis B surface antigen, and antibody to hepatitis B core antigen. Data from 745 vaccinees (93.1%), analyzed at the 7th month of follow-up, showed no significant difference in the seroconversion rates for Betagen (94.4%) vs Heptavax-B (97.3%), but the geometric mean titer of antibody was significantly higher for Heptavax-B (11 833 mIU/L) than for Betagen (4628 mIU/mL). The antibody response of Betagen was significantly and independently related to age and sex, while that of Heptavax-B was related to age only. Reported side effects from both vaccines were minor and mild, with approximately one fourth of all vaccinees reporting at least one side effect. Vaccinees, who had a protective level of antibody at the 7th month, were tested for antibodies at the 12th month. Of those in the Betagen-vaccinated group and those in the Heptavax-B-vaccinated group, 99.0% and 100%, respectively, were still protected. There was a proportionately larger decline in the geometric mean titers of antibody to hepatitis B surface antigen for Heptavax-B than for Betagen.

To estimate the rate of underreporting of AIDS (acquired immune deficiency syndrome) to the Federal Centre for AIDS (FCA), in 1988 the initials, date of birth and place of residence of 66 patients with AIDS known to the Toronto Sexual Contact Study (TSCS), 65 patients with AIDS known to the Vancouver Lymphadenopathy-AIDS Study (VLAS) and other participants in both studies who did not have AIDS were sent to the Bureau of Epidemiology and Surveillance, FCA. The FCA conducted a manual record linkage to link these data to the national registry of reported cases. The rate of underreporting was 12% (8/65) for the VLAS and 18% (12/66) for the TSCS. The specific diagnosis was not related to the rate of underreporting. For the TSCS the rate of underreporting had increased from 0% in 1983-84 to 44% in 1987-88 (p = 0.001). Differences in the observed rates of underreporting between the two studies are likely the result of differences in the reporting responsibilities of physicians involved in the studies.

Approximately 50 000 individuals are employed in various hospital-based occupations in Metropolitan Toronto. To determine the proportion of this population that might be considered as first-priority recipients of the new hepatitis B vaccine, a questionnaire was sent to the executive directors of 45 hospitals in this region. The questionnaire requested data on the numbers of full- and part-time employees whose frequency of contact with blood and blood-related equipment was the greatest. The response rate was 89%. Of the 9545 individuals identified as being at risk of exposure to hepatitis B, 5443 (57%) were nonphysicians and 4102 (43%) were physicians. A highly significant (p less than 0.001) positive and linear relation was found between the numbers of personnel at highest risk of exposure and the total number of hospital personnel and type of hospital. Therefore, the potential exists for developing and validating a simple bivariate model that could predict the initial vaccine requirements for hospital-based personnel in Ontario and other provinces.

A case-control study was conducted to investigate the risk of either fatty infiltration of the liver or cirrhosis, in males and females, in relation to varying levels of ethanol consumption. Male and female cases of fatty infiltration of the liver (47 males and 43 females) and male and female cases of cirrhosis (85 males and 66 females) were identified during 1981-1982 as part of a liver biopsy study in 6 teaching hospitals in Toronto. All cases were confirmed by biopsy. Male and female controls (394 males and 225 females) were obtained from 7 different local industries during the same period as part of a study for the early detection of liver disease. Cases and controls were interviewed by a nurse practitioner using a standard questionnaire designed to elicit data on daily and cumulative alcohol consumption. In both males and females, a dose-response effect between increasing levels of both daily and cumulative alcohol consumption and increasing risk of either fatty liver or cirrhosis was demonstrated and was independent of effects of age and duration of consumption. In males, risk for fatty liver was 1.37 (95% CL = 0.47, 4.0) for those consuming 40-59 g absolute alcohol/day compared to males consuming less than 40 g/day, rising to 50 (95% CL = 15.0, 170.7) for males consuming 80 or more g/day. In females, risk for fatty liver appeared at lower levels and was 2.82 (95% CL = 1.02, 7.82) for females consuming 20-59 g/day compared to females consuming less than 20 g/day, rising to 8.53 (95% CL = 2.12, 34.31) for females consuming 60 or more g/day.(ABSTRACT TRUNCATED AT 250 WORDS)

This study compared clinical and laboratory parameters in 37 individuals with serologic evidence of exposure to human T-cell lymphotropic virus type 3 (HTLV-III) and generalized lymphadenopathy. Basal levels of the interferon-induced enzyme, 2-5A synthetase were also measured and compared with the clinical parameters. A significant linear relationship (p less than .05) was demonstrated between the logarithm of the basal synthetase level and both the number and size of palpable nodes in the posterior cervical triangles of the men studied. No other lymph node chains demonstrated such a relationship. In addition, men with more than 3 palpable nodes (the median number) in the posterior triangles had lower mean levels of lymphocytes, reduced mean mitogen responses to PWM, PHA, and ConA, elevated mean levels of IgG, IgA, and IgM, and were more frequently anergic on skin testing. These findings suggest the need for further longitudinal study of the possibility that extent of lymphadenopathy and level of 2-5A synthetase might serve as useful parameters to monitor disease activity.

As part of a study of all patients undergoing liver biopsy in 6 Toronto teaching hospitals from February 1, 1981 to January 31, 1982, participants had hepatitis B marker (HBV) studies and were interviewed concerning, among other things, potential hepatitis B exposure risk factors. All analyses were conducted by sex. Of 376 males, and 342 females participating in the study, complete data were available on 243 (65%) males and 230 (67%) females. Information was obtained on country of birth, race, previous exposure to hepatitis, previous blood transfusions, sexual preference, use of intravenous drugs, occupation, tattooing, and ear piercing. Thirty-five percent of males and 17 percent of females had at least one HBV marker present. Males with at least one HBV marker, compared to males with no HBV markers were more frequently oriental (p less than 0.001), homosexual (p less than 0.05), or born in a country with a higher level of HBV endemicity than in Canada (p less than 0.001). Females with at least one HBV marker, compared to females with no HBV markers were more frequently oriental (p less than 0.001), employed in a health occupation (p less than 0.05), or born in a country with a higher level of HBV endemicity than in Canada (p less than 0.0001). For each sex, multiple logistic regression analysis was conducted to adjust for potential confounding by significant variables detected in univariate analyses.(ABSTRACT TRUNCATED AT 250 WORDS)

As the AIDS epidemic spreads, many patients are asking their primary-care physicians to perform AIDS (HIV-antibody) testing, and in some settings, clinical circumstances prompt physicians to consider ordering the test. As a result, thousands of HIV-antibody tests are being requested each month by Canadian family doctors, where none were available only two years ago. Yet particular characteristics of HIV infection make these tests very unlike most blood tests, since their use carries clear risks as well as benefits. The authors review these risks and benefits in two sequential articles. In this first paper, they review the quantitative aspects of test accuracy (validity). In a sequential paper, to be published in next month's issue, they will discuss the risks and benefits of performing the test in various clinical circumstances.

The relationship between liver cirrhosis death rates and certain nutritional factors was studied in 38 countries where mortality statistics were considered to be reliable. A partial correlation analysis showed that several food commodity consumption factors were independently and negatively (p less than 0.01) associated with liver cirrhosis death rates after adjustment for alcohol consumption. These factors were total calories, protein, fat, calcium, vitamin A and vitamin B2. The significant association of protein, vitamin A, vitamin B2 and calcium with the cirrhosis death rates is of importance since they were not intercorrelated with alcohol consumption. Further results showed that animal protein was more significantly related to cirrhosis death rates than vegetable protein. However, in view of certain limitations of this study, the findings do not necessarily reflect causal relationships but rather support the consideration by scientists that protein and vitamin deficiency may have certain effects on liver cirrhosis.

The levels of the 2'-5' oligoadenylate enzyme synthetase in extracts of peripheral blood mononuclear cells from individuals with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex (ARC) were measured and compared with synthetase levels in peripheral blood mononuclear cells (PBMs) from healthy heterosexual and homosexual controls. The mean basal synthetase level in heterosexual and homosexual controls was 14 +/- 13 and 12 +/- 9 pmol per hr/10(5) PBMs, respectively. Thirteen individuals with AIDS had a mean basal level of 129 +/- 75 pmol. Serial levels were persistently elevated in six of these individuals over a one- to 10-month period. Twelve of the 13 individuals had antibodies to human T cell lymphotrophic virus-III/lymphadenopathy-associated virus (HTLV-III/LAV). Thirty-three individuals with ARC had a mean basal synthetase level of 68 +/- 84 pmol. Thirty-two of the 33 had antibodies to HTLV-III/LAV. Eleven (33%) have had consistently normal synthetase levels (less than 2 SD above the mean for the homosexual controls, i.e., 30 pmol) over a three- to nine-month follow-up period. Fourteen (42%) had persistently elevated levels over the same period; four (29%) of these developed AIDS during the follow-up period. Eight have had fluctuating levels but have remained clinically well. These studies suggest that persistently elevated synthetase levels in individuals with ARC and antibodies to HTLV-III/LAV indicate progressive virus-induced disease activity. Elevated synthetase levels may be an important prognostic indicator of increased risk of progression to AIDS.

The relationships between the prevalence of hepatitis B surface antigen (HBsAg), mean annual per capita alcohol consumption and primary liver cancer (PLC) death rates were explored in 30 countries. HBsAg prevalence was associated, significantly, with the logarithm of the primary liver cancer death rate (simple correlation coefficient = 0.44, p less than 0.05). This significant association increased following adjustment for a country's mean annual per capita alcohol consumption (partial correlation coefficient = 0.53, p less than 0.01). A logarithmic linear relationship was also found between per capita alcohol consumption and the primary liver cancer death rate after adjustment for the country's prevalence of HBsAg (partial correlation coefficient = 0.38, p less than 0.05). Results from both correlation and regression analyses showed that prevalence of HBsAg was more significantly associated with PLC death rates than was alcohol consumption. However, these two variables were independently related to the PLC death rate in a stepwise multiple regression model. We could not demonstrate an interaction between the two variables. These findings are consistent with the prevailing view that chronic hepatitis B infection is the major factor in the most common form of primary liver cell cancer, hepatocellular carcinoma. In addition, they support the notion that alcohol consumption contributes significantly and independently, although probably to a lesser extent than hepatitis B, to deaths from that disease.

A cohort of 61 patients with Kaposi's sarcoma (KS) and AIDS was seen in the Oncology Unit of the Toronto General Hospital between 1982 and 1986. In an attempt to identify prognostic variables, laboratory and clinical parameters were examined using Kaplan-Meier estimates and the Cox Regression Model. All patients were male, median age 36 years (range 23-52). In 49 patients KS was diagnosed before any AIDS-associated opportunistic infection (OI). Three patients had concurrent KS and OI, and nine patients developed KS one or more months after an OI. Only 11 patients had stage I or II disease, 34 stage III, and 15 stage IV. Only 18 patients (30%) were asymptomatic. Twenty-six percent had fever, night sweats, or weight loss, 11% had minor opportunistic infections, and 33% had both symptom complexes. The median overall survival was 10.5 months. The survival of patients who received chemotherapy for their KS was not significantly different from the survival of non-treated patients (p = 0.7). Although significant differences in survival could not be seen between stages, patients with both systemic symptoms and minor opportunistic infections had significantly shorter survival (p = 0.03). Survival from the onset of KS was significantly shorter for patients who had experienced a previous OI, but their overall survival from the date of diagnosis of AIDS was not significantly different from those patients presenting with KS alone. When analyzed separately the laboratory parameters of hemoglobin (p less than 0.0001), absolute lymphocyte count (p = 0.03), platelet count (p = 0.04), and T4 level (p = 0.05) demonstrated a significant relationship with survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Following their first article on HIV-antibody tests,(1) the authors, in this second article, on HIV-antibody testing focus on the benefits and risks that may result from use of the tests. The sequelae of testing, especially if the result is positive, often differ widely, depending on the person tested and on those around him/her. Significant social and psychiatric risks may outweigh any medical benefit of testing, especially for certain persons known to be at high risk of HIV infection. Accordingly, a detailed protocol is suggested for managing both patient requests and physician-perceived indications for HIV-antibody testing. The authors outline the preferred approach to obtaining informed consent, a prerequisite, in their opinion, for ordering the tests.

A total of 246 healthy male sexual contacts of men with either acquired immunodeficiency syndrome (AIDS) or an AIDS-related condition were recruited into a prospective study in Toronto, Canada between July 1984 and July 1985. At induction, data were collected on the sexual relationship between the contact and his primary case, sexual activities with other men, history of sexually transmitted diseases and other diseases, and use of recreational drugs. At recruitment, 144 sexual contacts had antibodies to human immunodeficiency virus (HIV); 102 of the contacts were seronegative at induction and at three months following recruitment. No association between HIV seropositivity and total number of sexual partners could be demonstrated. In univariate and multivariate analyses, receptive and insertive anal intercourse with the primary cases, and activities which either indicated or potentially caused anorectal mucosal injury (rectal douching, perianal bleeding, receipt of objects in ano, and receptive fisting) were strongly associated with HIV seropositivity. In the final multiple logistic regression model, two significant interaction effects were observed: the interaction between receptive anal intercourse and insertive anal intercourse and that between receptive anal intercourse and the anorectal mucosal injury index. These two interaction terms had negative regression coefficients which suggested that change in one sexual activity would not decrementally reduce risk of HIV infection without a comparable modification in the other activity. No association could be demonstrated between oral-genital and oral-anal sexual contact and odds ratios for these sexual activities declined to levels below 1.0 when adjusted for frequency of receptive anal intercourse.

Correlation and regression analyses have been carried out to test the hypothesis that areas experiencing high per capita consumption of absolute alcohol will also experience correspondingly higher annual rates of cirrhosis, in Ontario from 1978 to 1982. Adjustment was made for the influence of socio-demographic variables upon hospital morbidity and mortality rates. Areas experiencing higher per capita consumption of absolute alcohol were found to have higher hospital morbidity. The relationship between hospital morbidity and general mortality from cirrhosis, and per capita consumption of absolute alcohol appears to be growing weaker; no relationship could be demonstrated, however, between cirrhosis mortality and hospital morbidity and proportionate native population and education status.