Introduction
Young people represent almost half of all HIV infections worldwide [1]. The HIV epidemic in Russia, the largest in eastern Europe and central Asia, is most heavily concentrated among youth: 15–30-year-old individuals comprise 80% of total infections [1]. Young people living part time or full time on the street, known as ‘street youth’, constitute a group particularly at risk. Multiple factors lead youth to the streets, including abuse or neglect at home or in an orphanage, abandonment, and parental substance abuse or death [2–6]. Although many street youth have living parents, they do not receive parental support and are considered ‘social orphans’ [7]. Street youth often organize into groups as they negotiate survival, perform odd jobs, use narcotics and alcohol, engage in unprotected sex, among other risky behaviors. Such a lifestyle puts them at risk of many adverse health outcomes, including HIV/AIDS [8].
Experts estimate there are 1–3 million street youth in Russia [7]. Although the Russian street youth population is clearly at risk of HIV/AIDS [9,10] and has a size comparable to or greater than that of other risk groups (injection drug users, commercial sex workers, men who have sex with men) [8,11], a systematic assessment of their HIV seroprevalence has not been reported. Estimating HIV seroprevalence among street youth is challenging because of their elusive and transient lifestyle. Some evidence suggests high HIV seroprevalence among street youth in St Petersburg, the second largest Russian city. In 2005, Doctors of the World–USA (DOW) conducted HIV testing along with a behavioral survey in a convenience sample of 69 street youth at two metro stations and found an HIV seroprevalence of 30.4% [12]. This survey revealed a wide range of social problems, high sexual activity and the use of injection drugs [12]. Our purpose was to assess HIV seroprevalence systematically among street youth in St Petersburg and describe the characteristics associated with HIV infection.
Methods
The assessment of HIV seroprevalence among street youth was conducted in St Petersburg between January and May of 2006 in collaboration with the City AIDS Center, DOW, the US Centers for Disease Control and Prevention, and a number of non-governmental organizations working with street youth in St Petersburg. The study had two phases: (i) developing a sampling frame of street youth locations and randomly selecting study sites; and (ii) HIV testing and interviewing all eligible youth at each site.
To develop the sampling frame, DOW, in collaboration with other organizations serving street youth, conducted comprehensive mapping of all locations where street youth were known to, or could potentially, congregate, including metro stations, train stations, street markets, and food programme sites. These locations were classified as definite (reported by two or more organizations), presumptive (reported by one organization), and potential (neighborhoods with locations where street youth typically congregate but not reported by any organization). Outreach workers evaluated each known or potential location and created a sampling frame of all locations where five or more street youth were observed over a 1-h period. After the mapping, conducted during 3 months preceding HIV testing, 41 locations throughout the city were identified, of which 22 study sites were randomly selected to enroll approximately 300 youth.
Two mobile teams working together used vans equipped for counseling and HIV testing to conduct the field assessment. Teams visited all selected sites during hours when street youth usually congregated, and outreach workers approached all youth at each site to evaluate eligibility. Eligibility criteria included age of 15–19 years, being found at a street venue without a parent, and one of the following: living part or full time on the street, being out of family care, being self-identified as ‘street youth’, or attending school irregularly or not at all. Exclusion criteria were previous participation in the same assessment, inability to provide informed consent (e.g. inability to answer questions about the study's purpose), potential threat to project team, and possibility of undue harm by learning one's HIV status. Participants received booklets with information on HIV prevention and services, condoms, and gifts (such as food items) for their time. If time was insufficient to assess all eligible youth at the site in one visit, the mobile teams returned as many times as necessary to offer participation to all eligible youth. If no youth were present at a given site, the team returned twice to that site on different days/times to confirm the absence of street youth activity.
For eligible street youth who gave verbal informed consent confirmed by two witnesses, trained social workers completed pretest counseling and administered a structured questionnaire, and a nurse performed HIV testing of whole blood samples drawn by fingerstick using the Determine rapid HIV-1/2 test (Abbott Laboratories, Abbott Park, Illinois, USA). After the interpretation of rapid test results (within approximately 15 min), all youth received posttest counseling, which included counseling for a preliminary positive result for those with a reactive rapid HIV test. Active follow-up services were offered to HIV-positive youth, including referral to an overnight shelter and being accompanied the following day by the social worker (who conducted the posttest counseling) to the City AIDS Center. The Center provides state-financed services for HIV-infected individuals, including clinical, immunological, and virological evaluation, and antiretroviral treatment, care, and support. Youth were also referred to drop-in centers or local rehabilitation centers for ongoing care and support.
All analyses were performed using SAS-callable SUDAAN software (Research Triangle Institute, Research Triangle Park, North Carolina, USA) to adjust for intracluster homogeneity within sites. Chi-square tests were computed to assess the association between each characteristic and having a positive rapid HIV test. Unadjusted odds ratios were computed for all significant demographic, social, sexual, and lifetime substance use characteristics, as well as for non-significant a priori recognized predictors (length of time on the streets and lifetime exchange of sex for goods). Logistic regression was used to calculate adjusted odds ratios (AOR) and 95% confidence intervals. As a result of multicollinearity among several social factors and drug use behaviors, separate models were built for testing the significance of demographic, social, sexual, and substance use characteristics. Finally, we used chi-square tests of independence to assess sex differences in the HIV risk profile.
This rapid assessment was conducted as an emergency response to a potential public health crisis among street youth in St Petersburg. The project was reviewed for human subject concerns by the Centers for Disease Control and Prevention and the St Petersburg City Health Committee and was determined to be exempt from Institutional Review Board evaluation because of its focus on public health practice. Given the sensitivity of the data, confidentiality was given a foremost priority during all stages of the study, including enrolment, data collection, storage and analysis. No identifying information was collected; only nicknames, collected from HIV-infected youth by local project staff, were used for linking participants into follow-up care, support and treatment (if necessary).
Results
Of the 22 sites selected, no street youth were found at four sites; street youth were believed to have moved either voluntarily or by the police. Of 456 street youth approached at the remaining 18 sites, 341 (74.8%) were eligible, with an average of 19 (range 2–49) eligible youth per site. Of 341 eligible youth, 313 (91.8%) were included in the assessment, 26 (7.6%) refused to participate, and two were excluded because of the misrepresentation of their age.
Among participants, 63.3% were male and 53.4% were 18–19 years old (Table 1). Many youth had social risk factors, including not attending school for three or more years, being a single (one parent dead) or double (both parents dead) orphan, having no place to live, ever living in an orphanage, not having someone to turn to for help, and having a history of being abused. Most youth (95.9%) reported having had sex and many had a history of sexually transmitted infection (STI), been pregnant or having got someone pregnant, exchanged sex for goods, had anal sex, multiple sex partners, and inconsistently used condoms. The majority (84.7%) of youth had used some type of drug during their lifetime, including the use of injection drugs (50.7%) and inhalants (55.2%).
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Table 1: Street youth characteristics and HIV seroprevalence, St Petersburg, Russia, April–May 2006.
Table 1: (continued)
In our study population, 37.4% (95% confidence interval 26.1%, 50.2%) of youth had positive rapid HIV test results (Table 1). Youth with the highest HIV seroprevalences included those out of school for three or more years (54.5%), double orphans (64.3%), youth with no place to live (86.1%), youth who had ever lived in an orphanage (59.8%), and those with no one to turn to for help (51.2%). Furthermore, the following sexual and drug use risk behaviors were associated with the highest HIV seroprevalences: exchanging sex for goods (53.3%); previous diagnosis with an STI (70.5%); ever and current use of injected drugs (68.2 and 78.6%, respectively), shared needles (79.8 and 86.4%), Stadol (butorphanol tartrate, a narcotic-like pain reliever available in local pharmacies to February 2006 without a prescription; 75.0 and 82.3%), heroin (72.6 and 78.1%), inhalants (59.4 and 60.5%), ephedrine (65.6 and 52.2%), and obtaining drugs from a pharmacy (79.2%) or dealer (53.1%).
Among risk factors for HIV seropositivity, predictors that led to an independently increased odds of a positive HIV test included age 18–19 years (AOR 1.8), being a double (AOR 3.3) or single orphan (AOR 1.8), having no place to live (AOR 2.4), having lived in an orphanage (AOR 2.9), past STI diagnosis (AOR 2.1), injection drug use (AOR 23.0), needle sharing (AOR 13.3), Stadol use (AOR 19.4), heroin use (AOR 7.3), ephedrine use (AOR 2.9), and inhalant use (AOR 6.2) (Table 2).
Table 2: Odds ratios for testing HIV positive, street youth, St Petersburg, Russia, April–May 2006.
In comparing HIV-infected male and female youth, we found similar prevalences of lifetime injection drug use (94.0 and 90.6%, respectively), sharing needles (73.5 and 66.7%), and exchange of sex for goods (12.1 and 18.2%; Table 3). Young men were significantly more likely to report currently having no place to live or living in a basement or an attic (46.4 versus 30.3%), currently living alone or with friends (70.2 versus 57.6%), ever living in an orphanage (62.7 versus 45.5%), and having two or more opposite-sex partners in the past year (71.1 versus 51.5%). Young women were more likely to report inconsistent condom use (93.8 versus 80.0%). The majority of HIV-positive youth had been out of school for three or more years, had been on the streets for one or more year, lived alone or with friends, and were St Petersburg city residents eligible for no-cost medical care. Along with the high prevalences of risky sexual and substance use behaviors, knowledge that such behaviors facilitate HIV transmission was high (Table 3).
Table 3: Characteristics of HIV-positive street youth (n = 117), by sex, St Petersburg, Russia, April–May 2006.
Table 3: (continued)
Of the 117 street youth with a positive rapid HIV test, 48 (41.0%) had known of their positive HIV serostatus before the assessment, whereas the other 69 (59.0%) learned of their positive HIV serostatus during this assessment. Previously diagnosed youth were significantly more likely than newly diagnosed youth to share needles (57.5 versus 34.8%) and use condoms inconsistently (93.6 versus 76.9%). During the year after the assessment, of the 117 HIV-infected youth, two died (one from AIDS-related causes) and 39 (33.3%) received clinical evaluation at the City AIDS Center. All 39 had Western blotting confirmation of HIV.
Discussion
We found an extraordinarily high HIV seroprevalence among 15–19-year-old street youth in St Petersburg, which in many subgroups was greater than 50% and in some exceeded 70%. Many social and behavioral risk factors were independent predictors of HIV infection. Almost all HIV-positive youth were sexually active; most had multiple partners and used condoms inconsistently.
Our findings suggest that St Petersburg street youth are one of the most at-risk populations, with an HIV seroprevalence higher than that reported for commercial sex workers or for men who have sex with men [13,14]. Injection drug use was the strongest modifiable risk factor, with greater than a 20-fold odds of HIV infection. Sexual and social risks were also significant independent predictors of infection. Street youth who were orphans, had ever lived in an orphanage, or who had no place to live were most susceptible. Although the role of sexual risk behaviors relative to drug use behaviors in the acquisition of HIV among street youth is uncertain, the former may contribute to the increasingly generalized transmission of HIV. Our study showed a high prevalence of risky behaviors despite relatively good knowledge that such behaviors facilitate HIV transmission. Moreover, an awareness of positive HIV status by previously tested street youth did not lead to the adoption of safer behaviors, as has been observed in other reports [15]. The observed lack of a reduction in risk behaviors among those who knew they were HIV positive may be explained by a perception of non-vulnerability or hopelessness [16,17], and limited access to effective public health programmes for HIV-infected youth.
To our knowledge, this assessment is the first to estimate HIV seroprevalence among street youth in Russia systematically, although reports of HIV among street youth in low-prevalence countries have indicated that this group is at particular risk of HIV infection, with seroprevalence of up to 16% [18–22]. Although our observation that St Petersburg street youth are highly involved in risky behaviors is consistent with previous reports from eastern Europe and other regions [10,16,22,23], the 79% HIV seroprevalence among current injection drug users and the 86% seroprevalence among those who shared needles are higher than rates previously reported for the region and are among the highest in the world [24–26].
These results should be interpreted in the light of the study's strengths and limitations. Sampling was systematic and based on a current mapping of key locations for street youth in St Petersburg. We have no reason to believe our sampling was biased; we used a random selection of sites with universal selection of eligible youth within each site. Moreover, few eligible youth refused participation. In light of our findings of remarkably high HIV seroprevalence, we considered the possibility that returning to the same sites may have been associated with increased participation at these sites of youth at higher risk of being HIV infected. When we restricted the sample to youth identified during the first site visit, we observed an HIV seroprevalence of 33.2%, suggesting that any bias associated with preferential participation during return visits to the same site appears to have been minimal. Although we lacked confirmatory Western blotting on many youth with positive rapid tests, the performance of the Determine rapid HIV test [27–29] and WHO policy indicate that one positive rapid HIV test can identify HIV infection for surveillance purposes in populations with greater than 10% seroprevalence [30]. If sensitive sexual and drug use behaviors were under-ascertained by self-report, we may have underestimated the odds ratios associated with these characteristics, as we do not expect that reporting was differential between HIV-infected and uninfected youth. This assessment was cross-sectional, and therefore it is not possible to determine whether HIV infection preceded or perhaps even contributed to being on the street (because of stigma) or whether life on the street preceded HIV infection. According to limited data reported by participants, the major reasons for being on the street included a propensity to vagrancy, conflict or abuse, and parental alcohol use; although a small number reported injection drug use as a major reason for street life, no one identified HIV infection as a reason (data not shown). Comparative data on the distribution of these behavioral characteristics in the general Russian population aged 15–19 years are not available.
Among street youth aged 15–19 years in St Petersburg, HIV seroprevalence is among the highest ever reported for this age group in eastern Europe. HIV infections were detected in six of 10 orphans, seven of 10 with previous diagnoses of STI, and eight of 10 current injection drug users. Without treatment, care, and support, it can be expected that many more of these HIV-infected youth will die during the next 5–10 years. Therefore, from a health and human rights perspective, concentrated attention to the social, behavioral, and medical risks that negatively affect the health and survival of this population constitutes an urgent priority. Furthermore, the epidemic magnitude of HIV infection among St Petersburg street youth, coupled with their high frequency of risky sexual and drug use behaviors makes them prime candidates for accelerated bridging of HIV into the general population. We expect the prevalence of high-risk behaviors among street youth to be similar across large Russian cities, and therefore we believe it is critical to assess HIV seroprevlence among street youth in other metropolitan areas. In the face of negative population growth projected during coming decades in Russia, the magnitude of this epidemic in at-risk youth may exacerbate this unfavorable demographic trend. For the benefit of both street youth and the general population, interventions known to be effective for HIV-infected street youth should be adapted, implemented, and evaluated [31,32]. Although evidence suggests that needle exchange and methadone maintenance programmes are among the most effective means of reducing HIV transmission among injection drug users [33,34], neither of these receives adequate governmental support; methadone is not approved for use in Russia and needle exchange has limited availability in St Petersburg. Our findings of discordance between HIV prevention knowledge and behaviors suggest that behavioral components of HIV prevention programmes, including drug rehabilitation services, need to be strengthened. Furthermore, for the younger children whose orphan or family status places them at high risk of a street-based lifestyle, every effort should be made to strengthen housing, foster family, educational, and vocational support programmes.
As a result of the country's extraordinary scientific, economic, political, and cultural capacity, Russia is positioned to pioneer coordinated, humane, cross-cutting, multidisciplinary, and multisectoral programmes that actively involve street youth themselves. This will help to address the global ‘appalling absence of programmes for, and engagement of, young people in the fight against the pandemic’, highlighted by United Nations Envoy Stephen Lewis at the XVIth International AIDS Conference [35].
Contributors
D. Kissin, L. Zapata, R. Yorick, P. Marchbanks, and S. Hillis participated in the design of the study, study implementation, data analyses, and drafting of the report. E. Vinogradova, G. Volkova, E. Cherkassova, A. Lynch, J. Leigh, and D. Jamieson participated in the design of the study, study implementation, and drafting of the report.
Acknowledgements
The authors would like to thank all the street youth of St Petersburg who participated in the assessment. They also wish to thank all the members of the assessment group for their selfless work: Elena Arkhipova, Elena Boguzh and Marina Margovich (counselors), Natalia Kirik (nurse), Larisa Kuzmina, Maria Nikitina, and Vyacheslav Yanston (outreach workers), and Arkady Genkin (information technology specialist). In addition, they would like to thank the St Petersburg City AIDS Center (Drs Lydia Kryga and Zoya Lisitsina) for their invaluable support; Tom Dougherty and Vandana Tripathi (DOW) for their help with the study design and implementation; Chandra Sivakumar (Larkin Street Youth Services) for providing training and help with preparation for the assessment. The authors are grateful to the State Center for Prevention of Child Neglect and Drug Addiction (director Vagan Kanayan, head of social work department Larisa Solodchenko) and the following non-governmental organizations for their participation and input: Doctors to Children (executive director Svetlana Suvorova), Children's Crisis Center (director Olga Slutskaya, social worker Maria Chugunova), Center for Innovations (director Elena Kuzmina, project coordinator Vera Klimova), Foundation for Child Protection (outreach worker Sergey Ryazanov), Humanitarian Action (director Alexander Tsekhanovich, project coordinators Alexey Volkov and Anastasia Kapustina), Stellit (director Maya Rusakova, project coordinator Guzel Nasyrova, social worker Olga Kolpakova).
Sponsorship: The study was funded by contributions to Doctors of the World–USA by an anonymous donor and Davidson College's Adopt-a-Country Campaign. The funding sources had no role in the study design, data collection, data analysis, data interpretation, or writing of the report. The corresponding author had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Disclaimer: The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the US Centers for Disease Control and Prevention. The use of tradenames is for identification purposes only and does not constitute endorsement by the Centers for Disease Control and Prevention or the US Department of Health and Human Services.
Conflicts of interest: None.
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