Almost 30 years into the HIV/AIDS epidemic, we have amassed enough evidence of effective prevention and treatment to halt and reverse the spread of HIV and AIDS by 2015. Yet this seemingly attainable goal – as agreed by every United Nations Member State as part of the Millennium Development Goals  – remains far off for most low- and middle-income countries in the world. One of the reasons for this is that HIV is highly stigmatized, as are many of the behaviors that serve as modes of transmission for the virus. Accordingly, a lack of political will coupled with a frequent lack of both financial and human resources hinder effective responses.
In countries where dialogue and open discourse on the more stigmatized drivers of the epidemic do not occur, there are distinct benefits to be gained from enabling learning from other countries facing similar challenges. The Asia region and the Eastern Europe and Central Asia (EECA) region – as defined by the Joint United Nations Programme on HIV/AIDS (UNAIDS) (Table 1)  – have several epidemiological characteristics relating to HIV which allow for interesting comparisons to be drawn. Although the two regions are at different stages of their respective epidemics, they both have largely concentrated HIV transmission driven by drug injecting, unsafe sex work, poor prison conditions and risky sex between men. Increasingly, in both regions, heterosexual transmission has begun to play a larger role, mainly through the partners of people who inject drugs and sex workers . National prevalence estimates in almost all countries in both regions are less than 1%, with the notable exception of Thailand in Asia, and Estonia, the Russian Federation and Ukraine in EECA (see Table 1). This is markedly different from the characteristics of the sub-Saharan African region, where the bulk of new HIV infections occur through heterosexual contacts in the seemingly lower risk general population and the regional prevalence is significantly higher .
The HIV responses in both regions have also taken similar trajectories. In Asia and EECA, at-risk groups are isolated and stigmatized, usually falling outside of the social, health and educational systems that might serve to reduce their vulnerability. Additionally, there are country examples from both regions where these high-risk behaviors are criminalized, making access to and provision of targeted services even more challenging. Crucially, however, there have been examples of successful HIV policies and practices for at-risk populations in both Asia and EECA, and this paper explores the possible lessons that can be shared between policy-makers and decision-makers in both regions.
Despite similarities in some characteristics of their HIV epidemics, there are significant demographic and economic differences between the Asia and EECA regions. Asia is the largest and most populous UNAIDS region, home to around 60% of the world's population  and a remarkable diversity of wealth, health and culture (to the extent that it is often divided into sub-regions for HIV analyses). By contrast, EECA is collectively home to more than 440 million people , and countries in this region are frequently grouped together in HIV analyses due to their physical proximity, historical ties and common epidemiological characteristics.
This article draws largely on data from UNAIDS and the Global Fund to Fight AIDS, Tuberculosis and Malaria. This approach is not without limitations: these sources are not formally peer-reviewed; the inherent problems in using global or regional estimates for HIV and AIDS are well documented ; and these problems are especially pronounced when employing data on marginalized populations such as people who inject drugs . Furthermore, this article focuses on overall patterns and trends in each region, thus overlooking large inter-country variations. The comparisons we draw from this non-systematic review are primarily illustrative and are intended to generate discussion.
The regional epidemics
Although adult HIV prevalence in Asia is less than 1% in every country except Thailand, the sheer size of the regional population still makes it home to around 4.7 million people living with HIV . Unlike in EECA, the regional epidemic in Asia seems to have reached a stage of stabilization, with estimated incidence generally falling and prevalence rising in some countries . To help illustrate the epidemic across the region, Table 1 shows estimates for the number of people living with HIV, HIV prevalence as a percentage of the population (in 2001 and 2007) and the number of recorded AIDS deaths for each Asian country (where data are available). India accounts for more than half the region's infections , although the highest estimated national prevalence rates are in Thailand (1.4% of adults aged 15–49 years), Cambodia (0.8%) and Myanmar (0.7%). Notably, the proportion of women living with HIV in Asia nearly doubled between 2000 and 2008, rising from 19 to 35% of all HIV patients .
By contrast, it is estimated that the less populous EECA region has fewer people living with HIV but a higher overall prevalence. Again, to help illustrate the regional epidemic, Table 1 provides estimates for the number of people living with HIV, HIV prevalence (from 2001 and 2007) and the number of recorded AIDS deaths for each EECA country with data. Significantly, EECA appears to be at a very different stage of its HIV epidemic, with HIV prevalence still rising after an explosive increase in reported new cases since the late 1990s. The number of people living with HIV has risen by two-thirds since 2001 (from 900 000 in 2001 to 1.5 million in 2008) . Across EECA, the highest HIV prevalence rates can be found in the two biggest countries: the Russian Federation (1.1%) and Ukraine (1.6%), followed by European Union member states Estonia (1.3%) and Latvia (0.8%). Notably, all four countries have seen major rises in HIV prevalence since 2001 (Table 1).
Specific HIV-risk populations play a similarly important role in both regional epidemics. Across Asia, HIV transmission has long been concentrated among groups such as people who inject drugs, sex workers and their clients, and men who have sex with men (MSM) . In EECA, transmission similarly centers on high-risk groups – particularly people who inject drugs. For example, injecting drug use accounted for 45% of newly diagnosed HIV cases in one study of Eastern Europe  (excluding the Russian Federation, where it is even higher). In both Asia and EECA, understanding risk group behaviors, characteristics and issues – especially the legal, social and logistical barriers to accessing HIV services – is essential if international targets are going to be met. Most notably, in order to achieve the Millennium Development Goal target of halting the spread of HIV by 2015 , HIV efforts in these two regions must focus on prevention, especially ‘low cost–high impact’ interventions such as those targeting people who inject drugs, sex workers and their clients, and MSM .
People who inject drugs
Of the estimated global total of 15.9 million people who inject drugs, both Asia and EECA each account for approximately one-quarter of this population . Given the vast difference in population size between these regions, this translates into much higher prevalence of injecting drug use in EECA. People who use drugs are estimated to account for 10% of global HIV cases and have long been recognized as a key driver for many HIV epidemics. Yet, in the context of the global prohibition of many drugs, these individuals face great stigma around the world through criminalization, social exclusion and a general lack of understanding and empathy in the general population.
According to a systematic review  by the United Nations Reference Group on HIV and Injecting Drug Use, Asia is home to over 4.5 million people who inject drugs, including over 2.3 million in China (0.25% of the population aged 15–64 years), 400 000 in Japan (0.47%) and over 200 000 in Malaysia (1.33%). Another report  estimates that more than one million people inject drugs in India, and more than 500 000 in Indonesia. Critically, 16% of the people who inject drugs in Asia are believed to be HIV-positive .
The EECA region is estimated to be home to more than 3.7 million people who inject drugs, including over 1.8 million people who inject drugs in the Russian Federation alone, and over 300 000 each in Azerbaijan and Ukraine . Azerbaijan has the highest estimated prevalence of injecting drug use in the world (5.2% of the population), and four of the five highest national prevalences in the world – all above 1.5% – are found in EECA . Several countries are noteworthy for especially high HIV prevalence rates among people who inject drugs, including Estonia (72%), Ukraine (42%) and the Russian Federation (37%) .
Men who have sex with men
Prevention and treatment efforts have long recognized MSM as a population at high risk for HIV, characterized by substantially higher HIV prevalence than the general population . Several surveys indicate that a significant proportion of both Asian and EECA MSM also have sex with women, increasing the risk of transmission to the general population . In both regions, the on-going stigmatization and criminalization of MSM can make it difficult to identify, estimate HIV prevalence among and target these individuals in prevention efforts . Reports from Ukraine indicate that HIV-positive MSM often prefer to attribute their infection to injecting drug use rather than to homosexual activity due to stigma . Homosexual intercourse remains illegal in three of the five Central Asian republics, and at least six Eastern European countries have banned public events for the lesbian, gay and bisexual community in the past decade [3,13]. In Asia, MSM often face similar constraints, creating barriers to HIV prevention and treatment: several Asian countries have laws that prohibit sexual activity between same-sex adults, and stigmatization of homosexuals is widespread.
The combination of risk factors often associated with MSM (such as numerous sexual partners and unprotected anal intercourse) has been a key factor behind accelerating HIV transmission rates in many Asian cities . Further, increasingly high levels of HIV have been reported in some MSM communities in Asia, notably in India and Indonesia .
In EECA, official surveillance data imply that MSM account for a modest share of new HIV infections, just 0.4% . However, several studies suggest that official data significantly underestimate the magnitude of both the MSM population and their HIV prevalence in EECA . To control HIV among MSM, it is first essential to recognize them as a major risk group and to accurately understand their role in epidemics.
Risky sex work is a major driver of HIV transmission in many Asian countries, including Cambodia, India, Indonesia, Nepal and Thailand  – especially where substantial overlaps exist between people who use drugs and sex worker populations. In Asia, the proportion of women who sell sex is estimated to be between 0.2 and 2.6% . The number of male clients is much higher , although both buying and selling sex is illegal in many countries. High client numbers are associated with higher HIV transmission rates. Inconsistent condom use is another key factor; studies in China and Hong Kong reported that 60 and 51% of sex workers, respectively, failed to use condoms .
HIV prevalence among sex workers varies from country to country, but it is consistently higher than in the general population. For instance, surveys indicate that prevalence among sex workers is 14.5% in Southern India, between 14 and 16% in Indonesia and 18% in Myanmar, whereas around 38% of trafficked women in Nepal are living with HIV [2,3].
Although injecting drug use remains the main driver of HIV transmission in EECA, sex work is still a significant concern, especially where it overlaps with drug injecting . In the Russian Federation and Ukraine, evidence shows that up to a third of sex workers also inject drugs . Meanwhile, the number of sex workers has increased in many countries in the region such as Kyrgyzstan and the Russian Federation . HIV prevalence among sex workers has been reported to be as high as 15% in the Russian Federation .
Policy responses for at-risk populations
People who use drugs
Guidelines from the United Nations system describe a ‘comprehensive package’ of nine interventions (see Box 1), which together would have the greatest impact on HIV prevention and treatment among people who inject drugs  and are backed by a wealth of scientific evidence supporting their effectiveness [20–23]. National examples of the successful implementation of this package – also commonly referred to as ‘harm reduction’  – can be found in both Asia and EECA.
Thailand, for example, has a well documented history of punitive approaches and human rights violations directed toward people who use drugs , but – with support from the Global Fund and other international organizations – has developed a range of public health and harm-reduction efforts targeting people who inject drugs, such as the peer-led Mitsampan Harm Reduction Centre in Bangkok, which provides sterile injecting equipment, food, information and support . China has also recently reformed its HIV policy to incorporate a range of interventions for people who inject drugs such as antiretroviral therapy and methadone maintenance therapy [27,28].
In EECA, the Global Fund is the main financier of harm-reduction services for people who use drugs, and there are several interesting examples of harm reduction being implemented at the national level . In Moldova, for example, coverage levels of harm-reduction interventions in prisons have received international acclaim, and the percentage of people living with HIV in Moldovan prisons has declined in recent years, as has the number of new cases of HIV and of hepatitis C .
However, the response in many EECA countries has been heavily influenced by the legacy of the former Soviet Union, and its emphasis on the medical discipline of ‘narcology’ (a subspecialty of psychiatry) to tackle drug dependence and harms [30,31]. The provision of opioid substitution therapy – a key component of the evidence-based ‘comprehensive package’ (Box 1) and endorsed by the WHO's Essential Medicines List – remains prohibited in the largest country in this region, the Russian Federation . Similarly, people who inject drugs in Ukraine were heavily stigmatized at the turn of the century and – despite HIV prevalence of 41.8% among this population – had no access to treatment and little access to prevention. However, in the last few years (and due in part to two large Global Fund grants administered by nongovernmental organizations), Ukraine has made significant improvements in the provision of harm reduction and HIV treatment for people who inject drugs. By July 2007, 645 needle and syringe program sites had reached more than 120 000 people  and by 2009, Ukraine was one of only seven countries in the world with more than 1000 of these sites . Additionally, the Government recently amended national policies to permit methadone maintenance therapy .
By 2010, there were estimated to be 82 countries across the world that had implemented needle and syringe programs, including 24 of the 25 countries (96%) in EECA and 15 of the 25 countries (60%) in Asia (see Table 2). Similarly, 70 countries across the world had implemented opioid substitution therapy for people who inject drugs, including 19 of the 25 countries (76%) in EECA and 10 of the 25 countries (40%) in Asia (Table 2). It should be noted, however, that the coverage of these interventions – both globally and in these two regions – was found to be well below international recommendations [33,35], as Table 2 demonstrates.
Men who have sex with men
Governments across both regions are beginning to acknowledge that engaging MSM is critical to HIV control. In 2006, under pressure from international donors and local communities, the Ukrainian government set targets for prioritizing MSM in its national HIV program. As elsewhere in EECA, civil society organizations provide most HIV services for MSM in the country, with financial backing from international donors. For example, the Global Fund supports 14 prevention projects targeting Ukrainian MSM , and in 2009, the Foundation for AIDS Research (amfAR) awarded two grants to such groups . In Asia, laws discriminating against homosexuality have recently been abolished in India and Nepal. In China, where MSM are estimated to account for 11% of all HIV cases, the government set ambitious targets in 2008 to implement various prevention and testing services for this population, although stigma and discrimination remain major problems for its members .
Stigma, criminalization and discrimination remain key obstacles to addressing HIV and sex work in EECA, complicating the already limited delivery of effective prevention and treatment efforts for this group. However, civil society organizations are developing and implementing effective programs for sex workers and their clients in low-resource settings , often with support from international organizations (for example, the Global Fund is the main financier of efforts targeting sex workers across Asia with the exception of India).
Recent efforts have increased condom use among sex workers in some countries. For example, prevention programs established by the National AIDS Control Office in India reach more than 80% of female sex workers in four heavily affected states, whereas the ‘100% condom use’ program in Thai brothels helped reduce HIV prevalence among female sex workers from an estimated 33.2% in 1994 to 5.3% in 2007 . Similar programs have also been implemented in Cambodia, China, Laos, Mongolia, Myanmar, the Philippines and Vietnam . Although these 100% condom use programs have been widely cited as successful in terms of reducing HIV prevalence in many sex work settings, numerous human rights organizations have argued for a review of this approach in light of reports of human rights violations, violence and persecution of sex workers in some countries within the context of these programs . There is, therefore, a need for caution in praising these programs, and a need for the strengthened participation of sex workers themselves in their design and implementation.
The regional HIV epidemics in Asia and EECA share several notable similarities, with instructive examples of good (and poor) practice in both. They both underscore the importance of targeting most-at-risk populations in order to provide universal access to HIV services and reach the target of halting the global spread of HIV by 2015.
The two regions also share significant challenges, particularly national ideologies that oppose proven, effective and cost-effective interventions to reduce HIV transmission. In EECA, this is possibly best exemplified by the Russian Federation, which continues to prohibit opioid substitution therapy despite the treatment's success in neighboring countries and extensive international evidence of its effectiveness [39,40] – a policy that has been described as a ‘willful denial of evidence’  and ‘one of the catastrophes in the history of HIV’ .
Like elsewhere in the world, another key issue for these regions is HIV coinfections and comorbidities. For example, HIV programs often overlook more widespread epidemics of hepatitis B, hepatitis C and sexually transmitted infections , despite significant overlaps with HIV and clear similarities in the most affected populations (e.g. people who inject drugs). An estimated two to three million people in the world live with both HIV and hepatitis B (for which a vaccine exists), whereas four to five million live with HIV and hepatitis C  – statistics made more alarming by the negative impact these diseases have on one-another's progress, and by evidence that at-risk populations such as people who inject drugs are often excluded from hepatitis and HIV treatment . HIV/TB coinfection is another major issue often ignored in countries across Asia and EECA, even though 9% of global TB cases are attributable to HIV .
Throughout both regions, criminalization, marginalization, stigmatization and the violation of basic human rights (such as the right to the highest attainable standard of health) frequently prevent the provision of HIV services to members of risk groups . Such obstacles are particularly true for MSM in EECA and for people who inject drugs in Asia. The global prohibition of injecting drug use and the many national laws against homosexuality and sex work further heighten the risks faced by these already vulnerable populations, making it extremely difficult to reach these people and provide them with the prevention, testing, counseling, treatment and care services to which they are entitled.
Finally, despite the central role that key populations play in the HIV epidemics of these two regions, monitoring and analysis of HIV and allied harms in these groups remains broadly inadequate. This shortcoming is due to issues described above (such as ideologies that promote ineffective responses and the criminalization of risk populations), inadequate surveillance systems in many countries  and systemic faults in the global HIV response. It is also due, in part, to characteristics of the populations themselves. For example, overlaps among risk groups make classification difficult, whereas HIV studies and interventions seldom consider, for example, transgender sexualities or the intermittent nature of sex work for many people .
There are numerous opportunities for policy- and decision-makers in these regions to extrapolate and adapt good practices from other countries facing comparable challenges. Lessons learned from work in other areas with concentrated epidemics, or with most-at-risk populations, may provide insight into viable advocacy, policy and planning, implementation or monitoring and evaluation strategies. As the evidence base for addressing most-at-risk groups in these regions continues to build, dialogue and awareness about these populations can also increase. The acknowledgement of these risk groups is, in itself, a required step toward universal access to HIV services.
Until improved data can be collected, not enough will be known about the behavior and HIV transmission within these groups, nor the factors that determine the extent to which concentrated epidemics become general ones. Such information is essential if countries are to ‘know their epidemics’ and respond with a comprehensive package of targeted prevention, testing, treatment and care services for those most at risk – not only in Asia and EECA but also around the world.
We would like to thank Nadja Curth and Stine Byberg of Copenhagen University, as well as Andy Seale and Jami Johnson of the Global Fund, for their contributions to this article.
The views expressed in this paper are those of the authors and do not necessarily represent the position of the Global Fund to Fight AIDS, Tuberculosis and Malaria.
Conflicts of interest: None.
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