Community coverage and HIV prevention: assessing metrics for estimating HIV incidence through syringe exchange

The First 40 Years of AIDS: Promising Programs, Limited Success

HIV-prevention program planning, implementation, and evaluation began in the United States shortly after reports of a mysterious, apparently acquired, immune deficiency syndrome appeared in summer 1981. In San Francisco, New York City, and elsewhere, members of LGBT communities responded by providing accurate information, giving support, and raising money. During the first decade of the AIDS pandemic (1981-1990), social and behavioral scientists contributed by designing theory-based and practical interventions, combining interventions into programs, and measuring impact on behavior change and HIV incidence. In the second decade (1991-2000), federal, state, and local agencies and organizations played a more prominent role in establishing policies and procedures, funding research and programs, and determining the direction of intervention efforts. In the third decade (2001-2010), biomedical interventions were prioritized over behavioral interventions and have dominated attempts in the fourth decade (2011-2020) to integrate biomedical, behavioral, and structural interventions into coherent, efficient, and cost-effective programs to end AIDS.

Measuring individual-level needle and syringe coverage among people who inject drugs in Myanmar

BACKGROUND

Myanmar has prioritised people who inject drugs (PWID) as a key population for HIV mitigation efforts, with targets for needle and syringe distribution set at a population level. However, individual-level coverage, defined as the percentage of an individual's injecting episodes covered by a sterile syringe, is a more sensitive measure of intervention coverage. We sought to examine individual-level coverage in a sample of PWID in Myanmar.

METHODS

We recruited 512 PWID through urban drop-in-centres in Yangon, Mandalay and Pyin Oo Lwin. Participants were administered a quantitative questionnaire covering five domains: demographics, drug use, treatment and coverage, and injecting risk behaviour. We calculated past fortnight individual-level syringe coverage, estimating levels of sufficient (≥100% of injecting episodes covered by a sterile syringe) and insufficient (<100%) coverage, and examined associations between key variables and insufficient coverage via logistic regression.

RESULTS

Our sample was predominately male (97%), employed (76%), and living in stable accommodation (96%), with a median age of 27. All participants reported heroin as the drug most frequently injected, and injected a median of 27 times in the past two weeks. Nineteen per cent of participants had insufficient coverage in the two weeks before interview. Insufficient coverage was positively associated with syringe re-use (AOR: 5.19, 95% CIs: 2.57, 10.48) and acquiring sterile syringes from a location other than a formal drop-in-centre (AOR: 2.04, 95% CIs: 1.08, 3.82). Participants recruited in Mandalay (AOR: 0.30, 95% CIs: 0.11, 0.80) and Pyin Oo Lwin (AOR: 0.39, 95% CIs: 0.18, 0.87) had lower odds of insufficient coverage than those recruited in Yangon.

CONCLUSION

Our study shows coverage in selected areas of Myanmar was comparable with studies in other countries. Our results inform the delivery of harm reduction services for PWID, specifically by encouraging the use of formal drop-in-centres, over other sources of syringe distribution, such as pharmacies.

Scoping out the literature on mobile needle and syringe programs-review of service delivery and client characteristics, operation, utilization, referrals, and impact

BACKGROUND

Needle and syringe program (NSP) service delivery models encompass fixed sites, mobile services, vending machines, pharmacies, peer NSPs, street outreach, and inter-organizational agreements to add NSP services to other programs. For programs seeking to implement or improve mobile services, access to a synthesis of the evidence related to mobile services is beneficial, but lacking.

METHODS

We used a scoping study method to search MEDLINE, PSYCHInfo, Embase, Scopus, and Sociological for relevant literature. We identified 39 relevant manuscripts published between 1975 and November 2017 after removing duplicates and non-relevant manuscripts from the 1313 identified by the search.

RESULTS

Charting of the data showed that these publications reported findings related to the service delivery model characteristics, client characteristics, service utilization, specialized interventions offered on mobile NSPs, linking clients to other services, and impact on injection risk behaviors. Mobile NSPs are implemented in high-, medium-, and low-income countries; provide equipment distribution and many other harm reduction services; face limitations to service complement, confidentiality, and duration of interactions imposed by physical space; adapt to changes in locations and types of drug use; attract people who engage in high-risk/intensity injection behavior and who are often not reached by other service models; and may lead to reduced injection-related risks.

DISCUSSION

It is not clear from the literature reviewed, what are, or if there are, a "core and essential" complement of services that mobile NSPs should offer. Decisions about service complement for mobile NSPs need to be made in relation to the context and also other available services. Reports of client visits to mobile NSP provide a picture of the volume and frequency of utilization but are difficult to compare given varied measures and reference periods.

CONCLUSION

Mobile NSPs have an important role to play in improving HIV and HCV prevention efforts across the world. However, more work is needed to create clearer assessment metrics and to improve access to NSP services across the world.

Recalibration of the limiting antigen avidity EIA to determine mean duration of recent infection in divergent HIV-1 subtypes

Background

Mean duration of recent infection (MDRI) and misclassification of long-term HIV-1 infections, as proportion false recent (PFR), are critical parameters for laboratory-based assays for estimating HIV-1 incidence. Recent review of the data by us and others indicated that MDRI of LAg-Avidity EIA estimated previously required recalibration. We present here results of recalibration efforts using >250 seroconversion panels and multiple statistical methods to ensure accuracy and consensus.

Methods

A total of 2737 longitudinal specimens collected from 259 seroconverting individuals infected with diverse HIV-1 subtypes were tested with the LAg-Avidity EIA as previously described. Data were analyzed for determination of MDRI at ODn cutoffs of 1.0 to 2.0 using 7 statistical approaches and sub-analyzed by HIV-1 subtypes. In addition, 3740 specimens from individuals with infection >1 year, including 488 from patients with AIDS, were tested for PFR at varying cutoffs.

Results

Using different statistical methods, MDRI values ranged from 88–94 days at cutoff ODn = 1.0 to 177–183 days at ODn = 2.0. The MDRI values were similar by different methods suggesting coherence of different approaches. Testing for misclassification among long-term infections indicated that overall PFRs were 0.6% to 2.5% at increasing cutoffs of 1.0 to 2.0, respectively. Balancing the need for a longer MDRI and smaller PFR (<2.0%) suggests that a cutoff ODn = 1.5, corresponding to an MDRI of 130 days should be used for cross-sectional application. The MDRI varied among subtypes from 109 days (subtype A&D) to 152 days (subtype C).

Conclusions

Based on the new data and revised analysis, we recommend an ODn cutoff = 1.5 to classify recent and long-term infections, corresponding to an MDRI of 130 days (118–142). Determination of revised parameters for estimation of HIV-1 incidence should facilitate application of the LAg-Avidity EIA for worldwide use.

Políticas de redução de danos no Brasil

Considerando a disseminação da epidemia de HIV e o controle de sua transmissão entre usuários de drogas injetáveis (UDI), estratégias de redução de danos foram incorporadas em diversos países, incluindo o Brasil. Considerando a emergência das drogas como tema central na agenda governamental, especialmente o crack, o presente artigo registra e discute as práticas observadas em um programa de pesquisa e atenção aos UDI: o UFO. Foram considerados aspectos tais como acesso e adesão do usuário, dificuldades de financiamento, sustentabilidade e avaliação de resultados. As etapas do estudo envolveram pesquisa documental, observação sistemática e entrevistas com informantes-chave. Destacamos características do UFO que poderiam contribuir para políticas de redução de danos no cenário brasileiro. O programa estudado se apresenta como um exemplo exitoso de iniciativas de redução de danos, obtendo sucesso no acesso e adesão desse grupo, favorecendo seu acesso aos serviços de saúde e prevenção de riscos associados ao uso de drogas.

Combination prevention: new hope for stopping the epidemic

HIV research has identified approaches that can be combined to be more effective in transmission reduction than any 1 modality alone: delayed adolescent sexual debut, mutual monogamy or sexual partner reduction, correct and consistent condom use, pre-exposure prophylaxis with oral antiretroviral drugs or vaginal microbicides, voluntary medical male circumcision, antiretroviral therapy (ART) for prevention (including prevention of mother to child HIV transmission [PMTCT]), treatment of sexually transmitted infections, use of clean needles for all injections, blood screening prior to donation, a future HIV prime/boost vaccine, and the female condom. The extent to which evidence-based modalities can be combined to prevent substantial HIV transmission is largely unknown, but combination approaches that are truly implementable in field conditions are likely to be far more effective than single interventions alone. Analogous to PMTCT, "treatment as prevention" for adult-to-adult transmission reduction includes expanded HIV testing, linkage to care, antiretroviral coverage, retention in care, adherence to therapy, and management of key co-morbidities such as depression and substance use. With successful viral suppression, persons with HIV are far less infectious to others, as we see in the fields of sexually transmitted infection control and mycobacterial disease control (tuberculosis and leprosy). Combination approaches are complex, may involve high program costs, and require substantial global commitments. We present a rationale for such investments and cite an ongoing research agenda that seeks to determine how feasible and cost-effective a combination prevention approach would be in a variety of epidemic contexts, notably that in a sub-Saharan Africa.

HIV among people who inject drugs in Central and Eastern Europe and Central Asia: a systematic review with implications for policy

BACKGROUND AND OBJECTIVES

HIV among people who inject drugs (PWID) is a major public health concern in Eastern and Central Europe and Central Asia. HIV transmission in this group is growing and over 27 000 HIV cases were diagnosed among PWID in 2010 alone. The objective of this systematic review was to examine risk factors associated with HIV prevalence among PWID in Central and Eastern Europe and Central Asia and to describe the response to HIV in this population and the policy environments in which they live.

DESIGN

A systematic review of peer-reviewed and grey literature addressing HIV prevalence and risk factors for HIV prevalence among PWID and a synthesis of key resources describing the response to HIV in this population. We used a comprehensive search strategy across multiple electronic databases to collect original research papers addressing HIV prevalence and risk factors among PWID since 2005. We summarised the extent of key harm reduction interventions, and using a simple index of 'enabling' environment described the policy environments in which they are implemented.

STUDIES REVIEWED

Of the 5644 research papers identified from electronic databases and 40 documents collected from our grey literature search, 70 documents provided unique estimates of HIV and 14 provided multivariate risk factors for HIV among PWID.

RESULTS

HIV prevalence varies widely, with generally low or medium (<5%) prevalence in Central Europe and high (>10%) prevalence in Eastern Europe. We found evidence for a number of structural factors associated with HIV including gender, socio-economic position and contact with law enforcement agencies.

CONCLUSIONS

The HIV epidemic among PWID in the region is varied, with the greatest burden generally in Eastern Europe. Data suggest that the current response to HIV among PWID is insufficient, and hindered by multiple environmental barriers including restricted access to services and unsupportive policy or social environments.

Syringe coverage in an Australian setting: does a high level of syringe coverage moderate syringe sharing behaviour?

We examined individual-level syringe coverage among 417 people who inject drugs who were recruited from pharmacies in New South Wales in 2009. There was a U-shaped distribution of syringe coverage with many people having very high (51%) or very low (23%) coverage. Overall, two-thirds of respondents (63%) reported adequate coverage (≥ 100%). Respondents who had not used a needle and syringe program in the previous month were more likely to report inadequate coverage (AOR 2.25, 95% CI 1.25-4.05) as were those who reported daily or more frequent injecting (AOR 3.69, 95% CI 2.00-6.81). Inadequate syringe coverage was not independently associated with receptive needle sharing. The level of syringe coverage was high among this sample, and met targets set out by UNAIDS and other organisations. We found that inadequate syringe coverage was not independently correlated with receptive needle sharing, possibly because coverage is sufficient to diminish the relationship between syringe availability and sharing behaviours.

The HIV Epidemic: High-Income Countries

The HIV epidemic in higher-income nations is driven by receptive anal intercourse, injection drug use through needle/syringe sharing, and, less efficiently, vaginal intercourse. Alcohol and noninjecting drug use increase sexual HIV vulnerability. Appropriate diagnostic screening has nearly eliminated blood/blood product-related transmissions and, with antiretroviral therapy, has reduced mother-to-child transmission radically. Affected subgroups have changed over time (e.g., increasing numbers of Black and minority ethnic men who have sex with men). Molecular phylogenetic approaches have established historical links between HIV strains from central Africa to those in the United States and thence to Europe. However, Europe did not just receive virus from the United States, as it was also imported from Africa directly. Initial introductions led to epidemics in different risk groups in Western Europe distinguished by viral clades/sequences, and likewise, more recent explosive epidemics linked to injection drug use in Eastern Europe are associated with specific strains. Recent developments in phylodynamic approaches have made it possible to obtain estimates of sequence evolution rates and network parameters for epidemics.

Expanded syringe exchange programs and reduced HIV infection among new injection drug users in Tallinn, Estonia

BACKGROUND

Estonia has experienced an HIV epidemic among intravenous drug users (IDUs) with the highest per capita HIV prevalence in Eastern Europe. We assessed the effects of expanded syringe exchange programs (SEP) in the capital city, Tallinn, which has an estimated 10,000 IDUs.

METHODS

SEP implementation was monitored with data from the Estonian National Institute for Health Development. Respondent driven sampling (RDS) interview surveys with HIV testing were conducted in Tallinn in 2005, 2007 and 2009 (involving 350, 350 and 327 IDUs respectively). HIV incidence among new injectors (those injecting for < = 3 years) was estimated by assuming (1) new injectors were HIV seronegative when they began injecting, and (2) HIV infection occurred at the midpoint between first injection and time of interview.

RESULTS

SEP increased from 230,000 syringes exchanged in 2005 to 440,000 in 2007 and 770,000 in 2009. In all three surveys, IDUs were predominantly male (80%), ethnic Russians (>80%), and young adults (mean ages 24 to 27 years). The proportion of new injectors decreased significantly over the years (from 21% in 2005 to 12% in 2009, p = 0.005). HIV prevalence among all respondents stabilized at slightly over 50% (54% in 2005, 55% in 2007, 51% in 2009), and decreased among new injectors (34% in 2005, 16% in 2009, p = 0.046). Estimated HIV incidence among new injectors decreased significantly from 18/100 person-years in 2005 and 21/100 person-years in 2007 to 9/100 person-years in 2009 (p = 0.026).

CONCLUSIONS

In Estonia, a transitional country, a decrease in the HIV prevalence among new injectors and in the numbers of people initiating injection drug use coincided with implementation of large-scale SEPs. Further reductions in HIV transmission among IDUs are still required. Provision of 70 or more syringes per IDU per year may be needed before significant reductions in HIV incidence occur.

Estimating national-level syringe availability to injecting drug users and injection coverage: Switzerland, 1996-2006

BACKGROUND

Measuring syringe availability and coverage is essential in the assessment of HIV/AIDS risk reduction policies. Estimates of syringe availability and coverage were produced for the years 1996 and 2006, based on all relevant available national-level aggregated data from published sources.

METHODS

We defined availability as the total monthly number of syringes provided by harm reduction system divided by the estimated number of injecting drug users (IDU), and defined coverage as the proportion of injections performed with a new syringe, at national level (total supply over total demand). Estimates of supply of syringes were derived from the national monitoring system, including needle and syringe programmes (NSP), pharmacies, and medically prescribed heroin programmes. Estimates of syringe demand were based on the number of injections performed by IDU derived from surveys of low threshold facilities for drug users (LTF) with NSP combined with the number of IDU. This number was estimated by two methods combining estimates of heroin users (multiple estimation method) and (a) the number of IDU in methadone treatment (MT) (non-injectors) or (b) the proportion of injectors amongst LTF attendees. Central estimates and ranges were obtained for availability and coverage.

RESULTS

The estimated number of IDU decreased markedly according to both methods. The MT-based method (from 14,818 to 4809) showed a much greater decrease and smaller size of the IDU population compared to the LTF-based method (from 24,510 to 12,320). Availability and coverage estimates are higher with the MT-based method. For 1996, central estimates of syringe availability were 30.5 and 18.4 per IDU per month; for 2006, they were 76.5 and 29.9. There were 4 central estimates of coverage. For 1996 they ranged from 24.3% to 43.3%, and for 2006, from 50.5% to 134.3%.

CONCLUSION

Although 2006 estimates overlap 1996 estimates, the results suggest a shift to improved syringe availability and coverage over time.

Syringe exchange in community pharmacies--The Portuguese experience

BACKGROUND

Since 1993 the participation of Portuguese pharmacies to the national Syringe Exchange Programme (SEP) has remained high. However, no national guidelines or standard procedures are available regarding the provision of this service. We aimed to describe practices and attitudes toward syringe dispensing and other harm reduction strategies in Portuguese pharmacies.

METHODS

A cross-sectional survey was conducted using an anonymous self-administered questionnaire. All pharmacies in Portugal (n=2775) were invited to participate. The questionnaire addressed SEP ever involvement and discontinuation; injection equipment policies; problems and needs in service provision.

RESULTS

Participation rates were 69.6% among pharmacies involved in SEP and 42.7% in those not involved in the programme. Among current providers, 64.3% followed a strict "one-for-one" policy and 21.6% established limits on the number of syringes distributed. Syringe selling was reported by 76.2%. One-tenth of pharmacies supervised methadone consumption Problems in service provision were experienced by 12.8% of respondents. Need for increased training and improvement of referral pathways were frequently reported.

CONCLUSIONS

Pharmacy-based harm reduction interventions in Portugal have tended to follow strict policies favouring conservative approaches. Training and feedback adaptation seem indispensable to avoid service discontinuation and boost an activity with an essential humanitarian dimension.

Prevalence and predictors of transitions to and away from syringe exchange use over time in 3 US cities with varied syringe dispensing policies

Syringe exchange programs (SEPs) can reduce HIV risk among injecting drug users (IDUs) but their use may depend heavily on contextual factors such as local syringe policies. The frequency and predictors of transitioning over time to and from direct, indirect, and non-use of SEPs are unknown. We sought, over one year, to: (1) quantify and characterize transition probabilities of SEP attendance typologies; (2) identify factors associated with (a) change in typology, and (b) becoming and maintaining Direct SEP use; and (3) quantify and characterize transition probabilities of SEP attendance before and after changes in policy designed to increase access. Using data collected from 583 IDUs participating in a three-city cohort study of SEPs, we conducted a latent transition analysis and multinomial regressions. Three typologies were detected: Direct SEP users, Indirect SEP users and Isolated IDUs. Transitions to Direct SEP use were most prevalent. Factors associated with becoming or maintaining Direct SEP use were female sex, Latino ethnicity, fewer injections per syringe, homelessness, recruitment city, injecting speedballs (cocaine and heroin), and police contact involving drug paraphernalia possession. Similar factors influenced transitions in the syringe policy change analysis. Policy change cities experienced an increase in Indirect SEP users (43-51%) with little increased direct use (29-31%). We found that, over time, IDUs tended to become Direct SEP users. Policies improving syringe availability influenced SEP use by increasing secondary syringe exchange. Interactions with police around drug paraphernalia may encourage SEP use for some IDUs and may provide opportunities for other health interventions.

Prevention of HIV infection for people who inject drugs: why individual, structural, and combination approaches are needed

HIV can spread rapidly between people who inject drugs (through injections and sexual transmission), and potentially the virus can pass to the wider community (by sexual transmission). Here, we summarise evidence on the effectiveness of individual-level approaches to prevention of HIV infection; review global and regional coverage of opioid substitution treatment, needle and syringe programmes, and antiretroviral treatment; model the effect of increased coverage and a combination of these three approaches on HIV transmission and prevalence in injecting drug users; and discuss evidence for structural-level interventions. Each intervention alone will achieve modest reductions in HIV transmission, and prevention of HIV transmission necessitates high-coverage and combined approaches. Social and structural changes are potentially beneficial components in a combined-intervention strategy, especially when scale-up is difficult or reductions in HIV transmission and injection risk are difficult to achieve. Although further evidence is needed on how to optimise combinations of interventions in different settings and epidemics, we know enough now about which actions are effective: the challenge is to deliver these well and to scale.

A situation update on HIV epidemics among people who inject drugs and national responses in South-East Asia Region

We explore the magnitude of and current trends in HIV infection among people who inject drugs and estimate the reach of harm reduction interventions among them in seven high-burden countries of the South-East Asia Region. Our data are drawn from the published and unpublished literature, routine national HIV serological and behavioural surveillance surveys and information from key informants. Six countries (Thailand, Myanmar, Nepal, Indonesia, India, and Bangladesh) had significant epidemics of HIV among people who inject drugs. In Thailand, Indonesia, Bangladesh, Myanmar and India, there is no significant decline in the prevalence of HIV epidemics in this population. In Nepal, north-east India, and some cities in Myanmar, there is some evidence of decline in risk behaviours and a concomitant decline in HIV prevalence. This is countered by the rapid emergence of epidemics in new geographical pockets. Available programme data suggest that less than 12 000 of the estimated 800 000 (1.5%) people who inject drugs have access to opioid substitution therapy, and 20-25% were reached by needle-syringe programmes at least once during the past 12 months. A mapping of harm reduction interventions suggests a lack of congruence between the location of established and emerging epidemics and the availability of scaled-up prevention services. Harm reduction interventions in closed settings are almost nonexistent. To achieve significant impact on the HIV epidemics among this population, governments, specifically national AIDS programmes, urgently need to scale up needle-syringe programmes and opioid substitution therapy and make these widely available both in community and closed settings.