Risk of HIV infection from transfusion with blood negative for HIV antibody in a west African city.

OBJECTIVE--To estimate the risk of infection with HIV (HIV 1 or HIV 2, or both) from transfusion of a screened unit of blood in a high prevalence area in west Africa. DESIGN--Retrospective cohort study for January-July 1991. SETTING--National Blood Transfusion Centre, Abidjan, Côte d''Ivoire. SUBJECTS--Repeat donors (5831 units of blood) and first time donors (5076 units) in the first five months of 1991. MAIN OUTCOME MEASURES--Prevalence and estimated incidence of HIV infection in repeat and first time donors; estimated rate of potentially infected, HIV antibody negative units; and rate of (false negative) potentially infected units assuming a laboratory test sensitivity of 99%. RESULTS--Overall HIV prevalence was 11.0% in first time donors and 2.1% in repeat donors. In the first seven months of 1991, 29 HIV antibody positive (27 HIV 1, 1 HIV 2, 1 dually reactive) donors with a seronegative unit of blood earlier in the year were identified; 26 had donated blood eight weeks or less before their estimated dates of seroconversion and may have been infectious (minimum rate 26/5831 (4.5/1000 potentially infected units)). Estimated incidence of infection in repeat donors was 1.2-2.5%. Laboratory test insensitivity would result in an estimated 1.1/1000 false negative units from first time donors and 0.2/1000 units from regular donors. The overall rate of potentially infected units (all donors, seroconversions, and errors) was estimated at 5.4-10.6/1000. CONCLUSIONS--The risk of HIV infection from a single unit of blood remains substantial (5.4-10.6/1000 units). To prevent infection from blood transfusion in areas of high incidence and prevalence of HIV all but absolutely essential transfusions should be avoided, and donors with low incidence of HIV infection should be selected.     

HIV infection among women undergoing abortion in Montreal.

OBJECTIVE: To determine the seroprevalence and correlates of HIV infection in a subpopulation of women of childbearing age in Montreal. DESIGN: Anonymous unlinked seroprevalence study. SETTING: Pregnancy termination unit in a teaching hospital in Montreal. PARTICIPANTS: Women presenting for abortion from July 1989 to June 1993 who resided in Quebec and were not known to have HIV infection; 12,017 (99.6%) of 12,068 eligible women were included in the study. INTERVENTION: HIV antibody testing of serum left over from samples obtained for routine Rh typing; the same algorithm as for serodiagnostic testing, namely enzyme immunoassay (EIA) followed by confirmatory testing of repeatedly EIA-reactive samples, was used. OUTCOME MEASURES: HIV serostatus by age, marital status, region of residence (metropolitan Montreal versus other), country of birth and number of living children. RESULTS: Most (84.7%) of the subjects resided in metropolitan Montreal. The median age was 27.0 (range 13 to 50) years. The serum samples of 22 women were confirmed to be HIV positive, for an overall seroprevalence rate of 1.8 per 1000 (95% confidence interval 1.1 to 2.8). The seroprevalence rate did not vary significantly by age, marital status, region of residence or study year. However, it was strongly correlated with country of birth: Canada 0.16, Haiti 23.5, HIV-endemic countries other than Haiti 5.3 and non-HIV-endemic countries other than Canada 0.0 per 1000. The seroprevalence rate among women born in Haiti was 147 times higher than that among women born in Canada (p < 0.0001). Of the women born in Haiti the rate was 3.0 times greater among those who immigrated to Canada in 1985 or later than among those who immigrated earlier (p = 0.047). CONCLUSIONS: The results of this study indicate that the HIV seroprevalence rate among women in Montreal is strongly associated with country of birth, women born in HIV-endemic countries, especially Haiti, having the highest rate. These results will help in the development of policies regarding HIV antibody testing and prevention of HIV transmission in Quebec.     

The study of activity of blood antioxidant enzymes in HIV infection

The HIV infection is accompanied by activation of lipid peroxidation, oxidative modification of lipoprotein complexes, and a decrease in activity of blood serum antioxidant enzymes (superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx)). A significant increase of glutathione reductase observed under these conditions is considered as the antioxidant defense function. These changes are observed at already stages of this disease (in HIV carriers), however, they were much more pronounced in patients with manifested forms of AIDS.     

Risk behaviours for HIV infection among drug users in prison.

OBJECTIVE--To study a group of injecting drug users to establish the degree of illicit drug use in prisons, the prevalence of risk behaviours for HIV infection, and the uptake of treatment for drug dependency with drugs within the prison system. DESIGN--Anonymous, self administered, questionnaire. SETTING--Two drug agencies in central London; one operating a scheme for exchanging needles, and the other offering drug advice and information. SUBJECTS--50 (42 Men, eight women) self selected injecting drug users (mean age 31.2 (range 21-42)), all of whom had been held in custody at some time since 1982. MAIN OUTCOME MEASURES--Details about periods served in custody since 1982; the number of respondents who took drugs (orally or by injection), either illicitly or prescribed, while in prison and the types of substances taken; the respondents'' sexual activity in prison and between periods in custody. RESULTS--The average time spent in custody before the study was 20.6 months (range 1-72). Most prosecutions were directly or indirectly related to drug taking. 47 Of the 50 respondents reported taking at least one illicit drug while in custody; 33 by injection, 26 of whom had shared injecting equipment. 30 Had been treated for drug dependency by the prescribing of drugs while in prison. While in custody, one woman and four men (with a mean of seven (range 2-16) male partners) had had sex. Between periods spent in custody, men reported having a mean of eight (range 0-90) female partners and women a mean of one (range 0-3) male partner. Three men had had sex with other men, with a mean of six (range 2-11) partners. Since their last period in custody, men had had a mean of two (range 0-18) female partners and women had had a mean of two (range 1-3) male partners. Five men had also had male partners. CONCLUSIONS--A high prevalence of injecting and sexual risk behaviours among injecting drug users within and between periods in custody has been shown. Most of these offenders continued to take drugs while in custody, and just over half not only injected drugs but shared equipment. Some of the male prisoners compounded their risk of HIV infection by engaging in sexual activity with multiple partners. Prisoners who then have multiple sexual partners after release place their partners in the community at particular risk of HIV infection. Although many of the drug users were prescribed drugs for their dependency, limited access to appropriate treatment, counselling, and health education may compound the situation.     

Hepatitis B virus infection among street youths in Montreal

BACKGROUND: Street youths are at high risk for many health problems, including sexually transmitted diseases and bloodborne infections. The authors conducted a cross-sectional anonymous study from December 1995 to September 1996 involving street youths in Montreal to estimate the prevalence of risk behaviours for hepatitis B virus (HBV) infection and of markers of past and present HBV infection. METHODS: Participants were 437 youths aged 14 to 25 meeting specific criteria for itinerancy who were recruited in collaboration with the 20 major street youth agencies in Montreal. Sociodemographic and lifetime risk factor data were obtained during a structured interview, and a blood sample was taken to test for HBV markers (hepatitis B surface antigen and antibodies to the hepatitis B core antigen). Univariate analyses and multivariate logistic regressions were conducted. RESULTS: The mean age of the subjects was 19.5 years; 69.3% (303/437) were males. Many subjects had high-risk behaviours: 45.8% (200/437) had injected drugs, 24.5% (107/436) had engaged in prostitution, and 8.7% (38/437) reported having a sexual partner with a history of unspecified hepatitis. The prevalence rate for one or both HBV markers was 9.2% (40/434) (95% confidence interval [CI] 6.7%-12.3%). Multivariate logistic regression analysis showed that being over 18 years of age (adjusted odds ratio [OR] 4.5, 95% CI 1.8-11.7), having injected drugs (adjusted OR 3.5, 95% CI 1.5-8.3) and having had a sexual partner who had unspecified hepatitis (adjusted OR 3.2, 95% CI 1.3-7.5) were all associated with HBV infection. INTERPRETATION: Street youths are at high risk for HBV infection. Early and complete HBV vaccination among this vulnerable population is urgently needed.