The behavioral risk factors for contracting HIV infection in the intravenous administration of narcotics in abusers of psychoactive substances in the city of Rostov-on-Don

150 persons (drug users) who had applied to the department of psycho-social consultations and voluntary tests for the presence of HIV infection and STD of the Regional AIDS Control Center, as well as partners of HIV-infected addicts in the intravenous use of drugs, were examined. Out of 150 examined persons 63 were found to be positive for HIV infection. Among dangerous behavioral patterns, characteristic of drug addicts introducing drugs intravenously, the practice of repeated aspiration of the drug into syringes from the dose of the drug solution, common for the whole group of addicts, was noted as the most widespread habit.     

The effect of a syringe-exchange program on a decrease in the risk of HIV infection among intravenous narcotic abusers in the city of Rostov-on-Don

The necessity and effectiveness of introducing the program of the exchange of syringes for intravenous drug users as a preventive and antiepidemic measure are discussed. Preventive and antiepidemic measures within the concept of harm reduction are described. The comparative analysis of materials obtained as a result of two sociological questionings, carried out in 1997-1998 among the representatives of the community (random nonrepeating choice) and in the middle of 1999 among the participants of the program revealed that the participants of the program had statistically significant changes in risky behavior patterns during the use of injection drugs.     

Risk behaviours for HIV infection among injecting drug users attending a drug dependency clinic.

To study a range of possible risk factors for HIV among injecting drug user patients attending a clinic in London were interviewed from November 1986 to November 1987. Serum samples were tested for viral markers. Of 116 patients, 101 had shared injecting equipment, 75 on the first occasion of injecting and 76 during the past year. Seventy said that sharing was because equipment was not available. In the past year 102 had been sexually active, a third having two to 20 partners; a quarter of the women had exchanged sexual intercourse for money. The four patients who were positive for antibody to HIV antigen had shared equipment or had intercourse with drug users from areas with a high prevalence of HIV. Eleven patients had injected drugs while in prison. Despite a low prevalence of HIV infection this infection remains a threat to drug users in London; strenuous efforts are still needed to prevent its further transmission.     

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.     

The prevention of HIV/AIDS among injection drug abusers and women in the sex business in the city of Kharkiv

A steady increase of the number of persons with drug addiction has been noted both on Kharkov and Kharkov Province. Since 1996 a considerable number of HIV-infected persons has been detected among injecting drug users (80-82% of them infected parenterally). Rapid evaluation, carried out in 1997 within the project "Harm Reduction", served as the basis for the creation of the Charity Fund "Scarlet Ribbon" collaborating with the UNAIDS Representation in the Ukraine and other international organizations. The information and educational activity of the Fund among injecting drug users is presented. The necessity of organizing additional stationary and mobile exchange stations of the syringe is pointed out.     

The prevention of HIV infection and STDs among injection drug addicts in Ukraine

In 1996-1998 joint pilot Projects of the National Committee and the UNAIDS Program were carried out in 10 Ukrainian cities. The behavior determinants contributing to the spread of HIV infection, common for all regions under study, were determined. They were linked with the injections of narcotic drugs, sexual behavior and the level of knowledge on the infection. The effectiveness of the projects was due to the 80% coverage of those drug addicts who could not be reached by common narcotic drug services; to the use of individual syringes (increased from 43% to 95%); to a decrease in the sale of ready-made drugs in used syringes to 14%; to an increase in the index of the return of used syringes; to an increase in the proportion of persons constantly using condoms (58%); etc. Still the situation was found to give no grounds for optimism, and the conclusion was made that the strategy of "decreasing the harm" must become the policy and strategy of the public health system.     

The prevention of HIV infection in abusers of psychoactive substances as a social behavioral problem

This research has made it possible to outline and illuminate a range of problems which should be solved in planning concrete measures for the prophylaxis of HIV infection among the users of psychoactive substances. Such measures should also include those aimed at preventing children and adolescents from getting accustomed to the use of drugs at an early age, as well as the search of ways for providing adequate and effective information on the consequences of using narcotic drugs, the prevention of passage from single cases of the tentative use of drugs to systematic narcotization, etc.     

Development of HIV infection epidemic among intravenous drug users in the Sverdlovsky region

The Sverdlovsky region takes the fourth place among the 89 subjects of the Russian Federation by the number of registered cases of HIV infection. Drug addiction has reached an excessive scale in this region: according to the data of express evaluation carried out by the Regional Narcological Hospital and the Regional AIDS Center, not less than 7-8% of persons aged 15-30 years constantly use injection drugs. The large-scale epidemic of injection drug addiction has led to the rapid spread of HIV among addicts. The first penetration of HIV into this population took place in 1996 and, starting from the year 2000, rapid, development of the epidemic began, taking the character of an avalanche. The peak of new cases of HIV infection fell on 2001 (9,230 cases were registered). The concentrated stage of the epidemic development is observed in the region at present, the prevalence of HIV infection among drug addicts being 13.8%. Children born from HIV-infected drug addicted mothers now represent a new risk group due to great difficulties in the prophylaxis of the vertical virus transmission.     

Smoking of crack cocaine as a risk factor for HIV infection among people who use injection drugs

Background

Little is known about the possible role that smoking crack cocaine has on the incidence of HIV infection. Given the increasing use of crack cocaine, we sought to examine whether use of this illicit drug has become a risk factor for HIV infection.

Methods

We included data from people participating in the Vancouver Injection Drug Users Study who reported injecting illicit drugs at least once in the month before enrolment, lived in the greater Vancouver area, were HIV-negative at enrolment and completed at least 1 follow-up study visit. To determine whether the risk of HIV seroconversion among daily smokers of crack cocaine changed over time, we used Cox proportional hazards regression and divided the study into 3 periods: May 1, 1996–Nov. 30, 1999 (period 1), Dec. 1, 1999–Nov. 30, 2002 (period 2), and Dec. 1, 2002–Dec. 30, 2005 (period 3).

Results

Overall, 1048 eligible injection drug users were included in our study. Of these, 137 acquired HIV infection during follow-up. The mean proportion of participants who reported daily smoking of crack cocaine increased from 11.6% in period 1 to 39.7% in period 3. After adjusting for potential confounders, we found that the risk of HIV seroconversion among participants who were daily smokers of crack cocaine increased over time (period 1: hazard ratio [HR] 1.03, 95% confidence interval [CI] 0.57–1.85; period 2: HR 1.68, 95% CI 1.01–2.80; and period 3: HR 2.74, 95% CI 1.06–7.11).

Interpretation

Smoking of crack cocaine was found to be an independent risk factor for HIV seroconversion among people who were injection drug users. This finding points to the urgent need for evidence-based public health initiatives targeted at people who smoke crack cocaine.People who inject illegal drugs are known to be at heightened risk of HIV infection and other blood-borne diseases. In 2007, more than 20% of all new cases of HIV infection recorded in Canada were attributed to injection drug use.¹ Behaviours associated with the use of particular injection drugs (e.g., cocaine and heroin) have been identified as key factors driving HIV transmission among drug users in various settings.² However, over the last decade, significant changes in the popularity of specific illegal drugs have been observed.^3,4 In recent years, cities across Canada have experienced an explosive increase in the use of crack cocaine, whereas some drugs, including heroin, appear to be less commonly used.^5–7 The proportion of drug users who smoke crack cocaine and are homeless or have marginal housing has recently been reported to be as high as 86.6% in Vancouver, 66.7% in Edmonton and 62.4% in Toronto.⁸In the United States, a seminal cross-sectional study involving inner-city young adults showed that smoking of crack cocaine was associated with HIV infection.⁹ However, in Canada, despite the documentation of changing patterns of drug use in many communities,⁸ little is known about the impact that increased smoking of crack cocaine has had on the HIV epidemic. This is problematic because public health programs for people who smoke crack cocaine have been highly controversial in Canada.⁶ We conducted a longitudinal study to evaluate whether smoking of crack cocaine has emerged as a risk factor for HIV infection among people who inject drugs.     

The strategy for the control of the spread of HIV infection in the city of Novorossiysk

The results of the work of the center for controlling the spread of HIV infection are discussed. The analysis of the epidemiological situation and the work on the projects, envisaging preventive measures among intravenous drug users permitted the realization of educational and behavior-changing programs in the city in 1999. The results of this work demonstrate the effect of various preventive measures, manifested by a decrease in the rate of the spread of HIV infection in the city not only among drug users, but also among other groups of the population.     

Understanding drug resistance for monotherapy treatment of HIV infection

The purpose of this study was to investigate strategies in the monotherapy treatment of HIV infection in the presence of drug-resistant (mutant) strains. A mathematical system is developed to model resistance in HIV chemotherapy. It includes the key players in the immune response to HIV infection: virus and both uninfected CD4⁺ and infected CD4⁺ T-cell populations. We model the latent and progressive stages of the disease, and then introduce monotherapy treatment. The model is a system of differential equations describing the interaction of two distinct classes of HIV—drug-sensitive (wild type) and drug-resistant (mutant)—with lymphocytes in the peripheral blood. We then introduce chemotherapy effects. In the absence of treatment, the model produces the three types of qualitative clinical behavior—anuninfected steady state, andinfected steady state (latency), andprogression to AIDS. Simulation of treatment is provided for monotherapy, during theprogression to AIDS state, in the consideration of resistance effects. Treatment benefit is based on an increase or retention in CD4⁺ T-cell counts together with a low viral titer. We explore the following treatment approaches: an antiviral drug which reduces viral infectivity that is administered early—when the CD4⁺ T-cell count is ≥300/mm³, and late—when the CD4⁺ T-cell count is less than 300/mm³. We compare all results with data. When treatment is initiated during the progression to AIDS state, treatment prevents T-cell collapse, but gradually loses effectiveness due to drug resistance. We hypothesize that it is the careful balance of mutant and wild-type HIV strains which provides the greatest prolonged benefit from treatment. This is best achieved when treatment is initiated when the CD4⁺ T-cell counts are greater than 250/mm³, but less than 400/mm³ in this model (i.e. not too early, not too late). These results are supported by clinical data. The work is novel in that it is the first model to accurately simultate data before, during and after monotherapy treatment. Our model also provides insight into recent clinical results, as well as suggests plausible guidelines for clinical testing in the monotherapy of HIV infection.     

Control of the HIV infection and drug dosage

An increasing number of sophisticated control algorithms become available in the current literature to optimize the HIV therapy. Unfortunately, the pharmacokinetics and pharmacodynamics of antiretroviral drugs are ignored and these algorithms remain purely theoretic. This issue is investigated explicitly in this paper. An elementary pharmacodynamics model is combined with a non linear feedback control computed from standard engineering methods. It is shown that it results in the design of a realistic dosage regimen which drives the immunological system close to the healthy equilibrium state. Although the problem is dealt as a single input system, it is argued that the procedure can be extended to a multitherapy design or to any available control law.     

HIV infection and risk behaviours among young gay and bisexual men in Vancouver

BACKGROUND: Young gay and bisexual men may perceive that the consequences of HIV infection have dramatically improved with the availability of highly active antiretroviral therapy. We therefore sought to identify trends in HIV infection rates and associated risk behaviours among young gay and bisexual men in Vancouver. METHODS: Prospective cohort study involving gay and bisexual men aged 18-30 years who had not previously tested HIV positive. Subjects were recruited through physicians, clinics and community outreach in Vancouver. Annually participants were tested for HIV antibodies and asked to complete a self-administered questionnaire pertaining to sociodemographic characteristics, sexual behaviours and substance use. Prevalence of HIV infection and risk behaviours were determined for eligible participants who completed a baseline questionnaire and HIV testing as of May 1998. The primary outcome was the proportion of men who reported having protected sex during the year before enrollment and who reported any episode of unprotected sex by the time of the first follow-up visit. RESULTS: A total of 681 men completed a baseline questionnaire and HIV testing as of May 1998. The median duration between baseline and the first follow-up visit was 14 months. The median age was 25 years. Most of the subjects were white and of high socioeconomic status. The majority (549 [80.6%]) reported having sex only with men; 81 (11.9%) reported bisexual activity. Of the 503 men who had one or more regular male partners, 245 (48.7%) reported at least one episode of unprotected anal sex in the year before enrollment; the corresponding number among the 537 who had one or more casual male partners was 140 (26.1%). The prevalence and incidence of HIV seropositivity were 1.8% (95% confidence interval [CI] 0.8%-2.8%) and 1.7 per 100 person-years [95% CI 0.7-2.7], respectively. Fifty-two (26.5%) of the 196 and 55 (29.7%) of the 185 men with regular partners who reported having practiced protected insertive and receptive anal sex in the year before the baseline visit reported engaging in these activities without a condom at the follow-up visit; the corresponding numbers among the 232 and 242 men with causal partners who had practiced protected insertive and receptive anal sex before the baseline visit were 43 (15.5%) and 26 (9.4%) respectively at follow-up. INTERPRETATION: The incidence of HIV infection is unacceptably high among this cohort of young gay and bisexual men. Preliminary results suggest a disturbing trend toward increasing levels of unprotected anal intercourse.     

Regional government policy in the area of preventing the spread of HIV infection and drug abuse among youth

In 1993 the Youth Social Service, aimed at the creation of favorable conditions for the development of young people, the realization of their rights, the preservation of their individuality, their self determination and self expression, the support of their innovative activities, was created in Kiev. The work on the prevention of the spread if HIV infection and injection drug use should be considered only in the aspect of the involvement of young people in the work on the prevention of negative phenomena. The prerequisite for these programs was the tendency to an increase in the number of manifestations of negative phenomena among young people in Kiev. One of the most complicated programs was the program "Harm Reduction" among injecting drug users. The main prospect in the realization of this program was the involvement of a large number of volunteers and training by the method "Per Education".