Prevalence of hepatitis C among injection drug users in England and Wales: is harm reduction working?

Investigating the sociodemographic and behavioural factors associated with hepatitis C virus testing amongst people who inject drugs in England, Wales and Northern Ireland: A quantitative cross-sectional analysis

BACKGROUND

Hepatitis C virus (HCV) transmission in the UK is driven by injecting drug use. We explore HCV testing uptake amongst people who inject drugs (PWID) in England, Wales and Northern Ireland, and identify factors associated with i) ever having an HCV test amongst people who have ever injected drugs, and ii) recently having an HCV test (within the current or previous year) amongst people who currently inject drugs (reported injecting drugs within the last year).

METHODS

We analysed data from the 2019 'Unlinked Anonymous Monitoring Survey' of PWID, using logistic regression.

RESULTS

Of 3,127 PWID, 2,065 reported injecting drugs within the last year. Most (86.7%) PWID had a lifetime history of HCV testing. In multivariable analysis, higher odds of ever testing were associated with: female sex (aOR=1.54; 95%CI 1.11-2.14), injecting duration ≥3 years (aOR=2.94; 95%CI 2.13-4.05), ever receiving used needles/syringes (aOR=1.74; 95%CI 1.29-2.36), ever being on opioid agonist treatment (aOR=2.91; 95%CI 2.01-4.21), ever being imprisoned (aOR=1.86; 95%CI 1.40-2.48) and ever being homeless (aOR=1.54; 95%CI 1.14-2.07). Amongst PWID who had injected drugs within the last year, 49.9% had recently undertaken an HCV test. After adjustment, factors associated with higher odds of undertaking a recent HCV test included: injecting crack in the last year (aOR=1.29; 95%CI 1.03-1.61), experiencing a non-fatal overdose in the last year (aOR=1.39; 95%CI 1.05-1.85), ever being on opioid agonist treatment (aOR=1.48; 95%CI 0.97-2.25), receiving HCV information in the last year (aOR=1.99; 95%CI 1.49-2.65) and using a healthcare service in the last year (aOR=1.80; 95%CI 1.21-2.67).

CONCLUSION

Results suggest that PWID who have experienced homelessness and incarceration - amongst the most vulnerable and marginalised in the PWID population - are engaging with HCV testing, but overall there remain missed testing opportunities. Recent initiates to injecting have highest HCV infection risk but lower odds of testing, and peer-education may help target this group.

Factors associated with recently acquired hepatitis C virus infection in people who inject drugs in England, Wales and Northern Ireland: new findings from an unlinked anonymous monitoring survey

Monitoring infections and risk in people who inject drugs (PWID) is important for informing public health responses. In 2011, a novel hepatitis C antibody (anti-HCV) avidity-testing algorithm to identify samples compatible with recent primary infection was introduced into a national surveillance survey. PWID are recruited annually, through >60 needle-and-syringe programmes and prescribing services. Of the 980 individuals that could have been at risk of HCV infection, there were 20 (2%) samples that were compatible with recent primary infection. These were more common among: those imprisoned ⩾5 times [8/213; adjusted odds ratio (aOR) 8·7, 95% confidence interval (CI) 2·04-37·03]; women (8/230; aOR 3·8, 95% CI 1·41-10·38); and those ever-infected with hepatitis B (5/56; aOR 6·25, 95% CI 2·12-18·43). This study is the first to apply this algorithm and to examine the risk factors associated with recently acquired HCV infection in a national sample of PWID in the UK. These findings highlight underlying risks and suggest targeted interventions are needed.

Hepatitis C virus infection epidemiology among people who inject drugs in Europe: a systematic review of data for scaling up treatment and prevention

BACKGROUND

People who inject drugs (PWID) are a key population affected by hepatitis C virus (HCV). Treatment options are improving and may enhance prevention; however access for PWID may be poor. The availability in the literature of information on seven main topic areas (incidence, chronicity, genotypes, HIV co-infection, diagnosis and treatment uptake, and burden of disease) to guide HCV treatment and prevention scale-up for PWID in the 27 countries of the European Union is systematically reviewed.

METHODS AND FINDINGS

We searched MEDLINE, EMBASE and Cochrane Library for publications between 1 January 2000 and 31 December 2012, with a search strategy of general keywords regarding viral hepatitis, substance abuse and geographic scope, as well as topic-specific keywords. Additional articles were found through structured email consultations with a large European expert network. Data availability was highly variable and important limitations existed in comparability and representativeness. Nine of 27 countries had data on HCV incidence among PWID, which was often high (2.7-66/100 person-years, median 13, Interquartile range (IQR) 8.7-28). Most common HCV genotypes were G1 and G3; however, G4 may be increasing, while the proportion of traditionally 'difficult to treat' genotypes (G1+G4) showed large variation (median 53, IQR 43-62). Twelve countries reported on HCV chronicity (median 72, IQR 64-81) and 22 on HIV prevalence in HCV-infected PWID (median 3.9%, IQR 0.2-28). Undiagnosed infection, assessed in five countries, was high (median 49%, IQR 38-64), while of those diagnosed, the proportion entering treatment was low (median 9.5%, IQR 3.5-15). Burden of disease, where assessed, was high and will rise in the next decade.

CONCLUSION

Key data on HCV epidemiology, care and disease burden among PWID in Europe are sparse but suggest many undiagnosed infections and poor treatment uptake. Stronger efforts are needed to improve data availability to guide an increase in HCV treatment among PWID.

Two decades of successes and failures in controlling the transmission of HIV through injecting drug use in England and Wales, 1990 to 2011

Responses to injecting drug use have changed focus over the last 20 years. Prevalence and incidence of human immunodeficiency virus (HIV) among people who inject drugs (PWID) in England and Wales were examined in relation to these changes. A voluntary unlinked-anonymous surveillance study obtained a biological sample and questionnaire data from PWID through annual surveys since 1990. Prevalence and incidence trends were estimated via generalised linear models, and compared with a policy time-line. Overall HIV prevalence among 38,539 participations was 1.15%. Prevalence was highest among those who started injecting before 1985; throughout the 1990s, prevalence fell in this group and was stable among those who started injecting later. Prevalence was higher in 2005 than 2000 (odds ratio: 3.56 (95% confidence interval (CI) 1.40–9.03) in London, 3.40 (95% CI 2.31–5.02) elsewhere). Estimated HIV incidence peaked twice, around 1983 and 2005. HIV was an important focus of policy concerning PWID from 1984 until 1998. This focus shifted at a time when drug use and risk were changing. The increased incidence in 2005 cannot be ascribed to the policy changes, but these appeared to be temporally aligned. Policy related to PWID should be continually reviewed to ensure rapid responses to increased risk.

Is the HCV-HIV co-infection prevalence amongst injecting drug users a marker for the level of sexual and injection related HIV transmission?

BACKGROUND

Amongst injecting drug users (IDUs), HIV is transmitted sexually and parenterally, but HCV is transmitted primarily parenterally. We assess and model the antibody prevalence of HCV amongst HIV-infected IDUs (denoted as HCV-HIV co-infection prevalence) and consider whether it proxies the degree of sexual HIV transmission amongst IDUs.

METHODS

HIV, HCV and HCV-HIV co-infection prevalence data amongst IDU was reviewed. An HIV/HCV transmission model was adapted. Multivariate model uncertainty analyses determined whether the model's ability to replicate observed data trends required the inclusion of sexual HIV transmission. The correlation between the model's HCV-HIV co-infection prevalence and estimated proportion of HIV infections due to injecting was evaluated.

RESULTS

The median HCV-HIV co-infection prevalence (prevalence of HCV amongst HIV-infected IDUs) was 90% across 195 estimates from 43 countries. High HCV-HIV co-infection prevalences (>80%) occur in most (75%) settings, but can be lower in settings with low HIV prevalence (<10%) or high HIV/HCV prevalence ratios (HIV prevalence divided by HCV prevalence>0.75). The model without sexual HIV transmission reproduced some data trends but could not reproduce any epidemics with high HIV/HCV prevalence ratios (>0.85) or low HCV-HIV co-infection prevalence (<60%) when HIV prevalence>10%. The model with sexual HIV transmission reproduced data trends more closely. The proportion of HIV infections due to injecting correlated with HCV-HIV co-infection prevalence; suggesting that up to 80/60/<20% of HIV infections could be sexually transmitted in settings with HCV-HIV co-infection prevalence between 50-60/70-80/>90%.

CONCLUSION

Substantial sexual HIV transmission may occur in many IDU populations; HCV-HIV co-infection prevalence could signify its importance.

Spatial mapping of hepatitis C prevalence in recent injecting drug users in contact with services

In developed countries the majority of hepatitis C virus (HCV) infections occur in injecting drug users (IDUs) with prevalence in IDUs often high, but with wide geographical differences within countries. Estimates of local prevalence are needed for planning services for IDUs, but it is not practical to conduct HCV seroprevalence surveys in all areas. In this study survey data from IDUs attending specialist services were collected in 52/149 sites in England between 2006 and 2008. Spatially correlated random-effects models were used to estimate HCV prevalence for all sites, using auxiliary data to aid prediction. Estimates ranged from 14% to 82%, with larger cities, London and the North West having the highest HCV prevalence. The methods used generated robust estimates for each area, with a well-identified spatial pattern that improved predictions. Such models may be of use in other areas of study where surveillance data are sparse.

Challenges and opportunities to integrating family members of injection drug users into harm reduction efforts within the Atlantic Canadian context

BACKGROUND

This paper explores injection drug users' (IDUs) relationships with non-drug using family members in order to understand the potential opportunities for, and challenges to, having these family members provide harm reduction services (e.g., clean syringes).

METHODS

The qualitative data for this paper were drawn from a larger study of IDUs' relationships with key individuals in their lives (e.g., friends, family members). Interviews were conducted with 115 IDUs from across Atlantic Canada living in both urban and rural areas.

RESULTS

IDUs report that their relationships with family members are variable and dynamic, often changing over time. IDUs and family members engage in a variety of strategies to protect themselves from the multiple harms associated with drug use. Several strategies of self-protection (e.g., discontinuing all contact) are antithetical to the provision of harm reduction supports by family members. However, other strategies are based on continued contact, providing a potential opportunity for the integration of harm reduction approaches. Some family members not only have contact but provide supports (e.g., emotional support, housing) thus potentially facilitating the integration of harm reduction. In a few instances, family members already provide harm reduction supports (e.g., safe space to use).

CONCLUSIONS

Conceptualizing addictions as a health and social justice issue, and providing appropriate interventions, may reduce some of the harms experienced by users and family members thus encouraging sustained relationships and greater integration of harm reduction approaches into the relationship. Targeted education to family members about harm reduction may also further encourage their involvement in such efforts. Likewise, supporting family members who are already providing harm reduction supports will likely assist in the scaling-up of harm reduction efforts.

Seroepidemiology and risk factors of hepatitis B virus in Aden, Yemen

BACKGROUND

There is little published data concerning hepatitis B virus (HBV) infection in Aden and no data concerning risk factors for infection. This study aimed to determine the prevalence of HBV infection and risk factors for infection in Aden, Yemen.

METHODS

A prospective cross sectional survey of individuals attending primary health care facilities was stratified by age and population size. Five hundred and thirty five participants were interviewed and serum was screened for the presence of Immunoglobin G HBV core antibodies (antiHBc). AntiHBc positive participants were tested for antibodies to hepatitis B surface antigen (HBsAg). A case-control analysis of risk factors for HBV was undertaken comparing risk factors between antiHBc positive cases and seronegative controls.

RESULTS

The age-standardized seroprevalence for antiHBc was 16.2% (95% confidence interval (CI) 13.1-19.3) and for HBsAg was 1.5% (95% CI 0.5-2.5). The seroprevalence of antiHBc and HBsAg was estimated to range from 5.5% and 0% in infants to 40% and 4.6% in adults, respectively (p<0.001). Age (AOR=1.03, 95% CI=1.01-1.05), household size (>5-9 members, AOR=2.9, 95% CI=1.1-7.6) and ownership of a landline telephone (AOR=2.8, 95% CI=1.3-5.8) were independent risk factors for HBV infection.

CONCLUSIONS

HBV is still a public health problem in this community, with older individuals having much higher prevalence than younger generations. The results of this study would categorise Aden as a low HBV endemic zone. Perinatal transmission does not seem to be a major route of transmission.

Survival of hepatitis C virus in syringes: implication for transmission among injection drug users

BACKGROUND

We hypothesized that the high prevalence of hepatitis C virus (HCV) among injection drug users might be due to prolonged virus survival in contaminated syringes.

METHODS

We developed a microculture assay to examine the viability of HCV. Syringes were loaded with blood spiked with HCV reporter virus (Jc1/GLuc2A) to simulate 2 scenarios of residual volumes: low void volume (2 microL) for 1-mL insulin syringes and high void volume (32 microL) for 1-mL tuberculin syringes. Syringes were stored at 4 degrees C, 22 degrees C, and 37 degrees C for up to 63 days before testing for HCV infectivity by using luciferase activity.

RESULTS

The virus decay rate was biphasic (t1/2alpha= 0.4 h and t1/2beta = 28 hh). Insulin syringes failed to yield viable HCV beyond day 1 at all storage temperatures except 4 degrees , in which 5% of syringes yielded viable virus on day 7. Tuberculin syringes yielded viable virus from 96%, 71%, and 52% of syringes after storage at 4 degrees, 22 degrees, and 37 degrees for 7 days, respectively, and yielded viable virus up to day 63.

CONCLUSIONS

The high prevalence of HCV among injection drug users may be partly due to the resilience of the virus and the syringe type. Our findings may be used to guide prevention strategies.

Prevalence and genotypes of hepatitis C virus among injecting drug users from Salvador-BA, Brazil

Hepatitis C virus (HCV) is the major infectious disease agent among injecting drug users (IDUs), with seroprevalence ranging from 50-90%. In this paper, serological and virological parameters were investigated among 194 IDUs, 94 ex-IDUs and 95 non-IDUs that were sampled by the "snowball" technique in three localities renowned for both intense drug use and trafficking activities in Salvador, Brazil. The majority of the participants were male, but sex and mean age differed significantly between IDUs/ex-IDUs and non-IDUs (p < 0.05). Anti-HCV screening revealed that 35.6%, 29.8% and 5.3% of samples from IDUs, ex-IDUs and non-IDUs, respectively, were seropositive. HCV-RNA detection confirmed that the prevalence of infection was 29.4%, 21.3% and 5.3% for IDUs, ex-IDUs and non-IDUs, respectively. Genotyping analysis among IDUs/ex-IDUs determined that 76.9% were infected with genotype 1, 18.5% with genotype 3 and 4.6% with a mixed genotype; this result differed significantly from non-IDUs, where genotype 3 was the most frequent (60%), followed by genotype 1 (20%) and a mixed genotype (20%). We report a significantly higher prevalence of HCV infection in IDUs/ex-IDUs compared to the control group (p < 0.001). Although the sample size of our study was small, the differences in HCV genotype distribution reported herein for IDUs/ex-IDUs and non-IDUs warrant further investigation.

Visual versus written cues: a comparison of drug injectors' responses. Have surveys using the written word underestimated risk behaviors for hepatitis C?

We examined differences in responses of injecting drug users (IDUs) about sharing injecting paraphernalia using written questions ("written cues") versus video recordings of IDUs engaged in sharing behaviors ("visual cues"). Data were collected in 2007 in cities Liverpool, England and Glasgow, Scotland (N = 204). Participants completed a computer-assisted questionnaire with questions about sharing asked using visual and written cues. McNemar's chi-squared tests and logistic regression models were used. Respondents provided significantly different responses to questions about sharing when asked using visual versus written cues; a considerable proportion of IDUs said they had never shared via front/back loading and via sharing water/bleach for flushing out injecting equipment using written cues but confirmed they had participated in these behaviors when asked using visual cues. Implications and future research are discussed.

Hepatitis C virus infection among drug injectors in St Petersburg, Russia: social and molecular epidemiology of an endemic infection

AIMS

To understand the epidemiology and transmission patterns of hepatitis C virus (HCV), the predominant blood borne-pathogen infecting injection drug users (IDUs), in a part of the former Soviet Union.

DESIGN

Cross-sectional respondent-driven sample of IDUs.

SETTING

St Petersburg, Russia.

PARTICIPANTS

A total of 387 IDUs were recruited in late 2005 and throughout 2006.

MEASUREMENTS

Participants were surveyed to collect demographic, medical and both general and dyad-specific drug injection and sexual behaviors. A blood sample was collected to detect antibodies to hepatitis C and to amplify viral RNA for molecular analysis. The molecular data, including genotypes, were analyzed spatially and linkage patterns were compared to the social linkages obtained by respondent-driven sampling (RDS) for chains of respondents and among the injection dyads.

FINDINGS

HCV infection was all but ubiquitous: 94.6% of IDUs were HCV-seropositive. Among the 209 viral sequences amplified, genotype 3a predominated (n = 119, 56.9%), followed by 1b (n = 61, 29.2%) and 1a (n = 25, 11.9%). There was no significant clustering of genotypes spatially. Neither genotypes nor closely related sequences were clustered within RDS chains. Analysis of HCV sequences from dyads failed to find associations of genotype or sequence homology within pairs.

CONCLUSIONS

Genotyping reveals that there have been at least five unique introductions of HCV genotypes into the IDU community in St Petersburg. Analysis of prevalent infections does not appear to correlate with the social networks of IDUs, suggesting that simple approaches to link these networks to prevalent infections, rather than incident transmission, will not prove meaningful. On a more positive note, the majority of IDUs are infected with 3a genotype that is associated with sustained virological response to antiviral therapy.

Hepatitis C infection among injecting drug users in England and Wales (1992-2006): there and back again?

Changes in hepatitis C virus (HCV) prevalence from 1992 to 2006 were examined by using 24,311 records from unlinked anonymous surveillance of injecting drug users in England and Wales. Bayesian logistic regression was used to estimate annual prevalence, accounting for changing recruitment patterns (age, gender, injecting duration, geographic region, interactions) and the sensitivity and specificity of different oral fluid testing devices. After controlling for these differences, the authors found that the adjusted HCV prevalence decreased from 70% (95% credible interval: 62, 78) in 1992 to 47% (95% credible interval: 43, 51) in 1998 before rising again to 53% (95% credible interval: 48, 58) in 2006. Women injecting drug users had a higher HCV risk than did men (odds ratio = 1.50, 95% credible interval: 1.31, 1.73). Two regions (London and North West) had a markedly higher HCV prevalence than did the rest of England and Wales. Among individuals who had injected for less than 1 year, the adjusted HCV prevalence in 2006 was higher than that in 1992 (28% vs. 19%, respectively). HCV infection can be prevented. The public health challenge in England and Wales is to increase action in order to regain a downward trend in HCV risk and the benefit that has been lost since 1998.

Assessing IDU prevalence and health consequences (HCV, overdose and drug-related mortality) in a primary care trust: implications for public health action

BACKGROUND

We report on an exercise to estimate the prevalence of injecting drug use (IDU) and associated harms in a single primary care trust.

METHODS

Covariate capture-recapture methods to estimate (i) IDU prevalence; respondent driven sampling to measure (ii) prevalence of HCV and HIV and record linkage to measure (iii) mortality risk.

RESULTS

(i) The overall estimated number of IDU was 5540 (95% confidence interval, CI: 4710-6780) for all cases and 3280 (95% CI: 1940-4610) for cases matched to primary care register, i.e. a prevalence of 2.2 and 1.3% aged 15-54, respectively. (ii) The prevalence of HCV, hepatitis B and HIV was: 53, 32 and 0.7%. Over 70% of IDU in Bristol reported having at least one vaccination for HBV; more than half of those who were HCV positive were undiagnosed. (iii) The all-cause and overdose mortality rates for IDU were 0.75 and 0.4% respectively; and the standardized mortality ratio was 7.8 (95% CI: 5.4-10.8).

CONCLUSION

Locally specific and useful intelligence on injecting and its health consequence can be generated to inform local public health action, and may contribute information to validate national prevalence estimates.

Estimating hepatitis C infection acquired in England, 1986–2000

Hepatitis C is a global health problem and in the UK seroprevalence studies have mainly concentrated on specific high-risk groups. The aim of this study was to determine changes in the prevalence of antibody to hepatitis C virus in England using residual specimens collected between 1986 and 2000 reflecting the general population. A cross-sectional study design using a convenience collection of serum specimens from adult patients submitted to laboratories in the years 1986, 1991, 1996 and 2000 from a total of 19 laboratories around England were investigated. The main outcome was to determine anti-HCV prevalence and the average incidence occurring between 1986 and 2000 and factors associated with infection. Multivariable analysis of results from all years showed there was a significant difference in prevalence between males and females (P<0·001), birth cohort (P<0·001) and by health region (P<0·001). An average of 0·72% (95% CI 0–1·65%) of those susceptible to HCV born between 1950 and 1970 were estimated to have acquired the infection between 1986 and 2000. Analysis of this convenience serum collection suggests that HCV prevalence is low in the general population, and is associated with period of birth, gender and health region. There was evidence to support a low incidence of HCV infection in those born between 1950 and 1970 over the period 1986–2000 which, at the population level, equated to a substantial burden of infection (~106 000 persons). Continued surveillance and prevention targeted at injecting drug users are essential for the control of hepatitis C in the UK.

Prevalence and incidence of hepatitis C in injecting drug users attending genitourinary medicine clinics

Surveillance reports and prevalence studies have indicated that injecting drug users (IDUs) contribute more to the hepatitis C epidemic in the United Kingdom than any other risk group. Information on both the prevalence and incidence of hepatitis C in IDUs is therefore essential to understanding the epidemiology of this infection. The prevalence of hepatitis C in specimens from the Unlinked Anonymous Prevalence Monitoring Programme collected in 1995, 1996, 1998, 1999, 2000, and 2001 was determined using residual syphilis serology specimens from IDUs attending 15 genitourinary medicine (GUM) clinics in and outside London. These specimens were tested for antibodies to hepatitis C virus (anti-HCV). Using this cross-sectional design, anti-HCV-negative specimens were tested for HCV RNA to identify incident infections during the 'window' period of infection, and thus to estimate HCV incidence. Results of the multivariable analysis showed that there was marked variation in prevalence by clinic (P<0.0001) and age (P<0.0001). Overall the majority of infections were in males and the overall prevalence in injectors declined over the study period from 36.9% to 28.7%. The annual incidence in these injectors was estimated as being 3.01% (95% CI 1.25-6.73). Over the study period HCV incidence decreased by 1.2% per year. Genotyping of the incident infections identified the most common genotype as type 1 with type 3 being more frequently seen after 1998. Of the prevalent infections, genotype 1 was the most common. The study has confirmed a higher prevalence of anti-HCV in IDUs in the London area compared to those outside London. How representative of the current injecting drug user population are IDUs attending GUM clinics is unclear. Even so, such studies allow prevalence and incidence to be estimated in individuals who have ever injected drugs and inform ongoing public health surveillance.

Capture—recapture and anchored prevalence estimation of injecting drug users in England: national and regional estimates

Capture—recapture (C—RC) using four data sources, one of which accounted for 81% of captured injectors, and multiple indicator methods (MIM) were used to obtain national, regional and local estimates of the prevalence of injecting drug use among opiate and/or crack cocaine users in England. Persons aged 15 to 64 years, in contact with health and/or criminal justice services during 2005/2006, and known to be using opiates and/or crack cocaine and injecting drugs were included in the C—RC analysis. The MIM analysis included indicators relating to drug treatment, drug-related deaths, population density and drug offences.

There were an estimated 130,000 opiate and/or crack cocaine users who injected drugs in 2005/06 (95% confidence interval 125,800 to 137,000), corresponding to 3.9 per thousand of the population aged 15 to 64 years (95% confidence interval 3.8—4.1). Regional variation in the prevalence of injecting was evident, ranging from 6.1 per thousand of the population aged 15 to 64 years in Yorkshire and the Humber (95% confidence interval 5.6 to 6.6) to 2.3 per thousand in the East of England (95% confidence interval 1.8 to 2.9). Application of gender and age-group distributions for treated injecting drug users (IDUs) to the prevalence estimates suggested that there were 97,200 male injectors (95% confidence interval 94,000 to 102,500) and 63,600 female injectors aged 25 to 34 years (95% confidence interval 61,500 to 67,000).

The prevalence estimates provide a basis from which numbers of current IDUs infected with hepatitis C virus (HCV) can be approximated.

Meta-regression of hepatitis C virus infection in relation to time since onset of illicit drug injection: the influence of time and place

The authors examined the relation between time since onset of illicit drug injection (time at risk) and rates of hepatitis C virus (HCV) infection by using meta-regression. In 72 prevalence studies, median time since onset of injection was 7.24 years and median prevalence was 66.02%. The model showed statistically significant linear and quadratic effects of time at risk on HCV prevalence and significantly higher prevalence in developing and transitional countries and in earlier samples (1985-1995). In developed countries post-1995, mean fitted prevalence was 32.02% (95% confidence interval: 25.31, 39.58) at 1 year of injection and 53.01% (95% confidence interval: 40.69, 65.09) at 5 years. In developing/transitional countries post-1995, mean fitted HCV prevalence was 59.13% (95% confidence interval: 30.39, 82.74) at 1 year of injection. In 10 incidence studies, median time at risk was 5.29 years and median cumulative HCV incidence was 20.69%. Mean fitted cumulative incidence was 27.63% (95% confidence interval: 16.92, 41.70) at 1 year of drug injection. The authors concluded that time to HCV infection in developed countries has lengthened. More rapid onset of HCV infection in drug injectors in developing/transitional countries resembles an earlier era of the HCV epidemic in other regions.

The HCV Synthesis Project: scope, methodology, and preliminary results

Background

The hepatitis C virus (HCV) is hyper-endemic in injecting drug users. There is also excess HCV among non-injection drug users who smoke, snort, or sniff heroin, cocaine, crack, or methamphetamine.

Methods

To summarize the research literature on HCV in drug users and identify gaps in knowledge, we conducted a synthesis of the relevant research carried out between 1989 and 2006. Using rigorous search methods, we identified and extracted data from published and unpublished reports of HCV among drug users. We designed a quality assurance system to ensure accuracy and consistency in all phases of the project. We also created a set of items to assess study design quality in each of the reports we included.

Results

We identified 629 reports containing HCV prevalence rates, incidence rates and/or genotype distribution among injecting or non-injecting drug user populations published between January 1989 and December 2006. The majority of reports were from Western Europe (41%), North America (26%), Asia (11%) and Australia/New Zealand (10%). We also identified reports from Eastern Europe, South America, the Middle East, and the Caribbean. The number of publications reporting HCV rates in drug users increased dramatically between 1989 and 2006 to 27–52 reports per year after 1998.

Conclusion

The data collection and quality assurance phases of the HCV Synthesis Project have been completed. Recommendations for future research on HCV in drug users have come out of our data collection phase. Future research reports can enhance their contributions to our understanding of HCV etiology by clearly defining their drug user participants with respect to type of drug and route of administration. Further, the use of standard reporting methods for risk factors would enable data to be combined across a larger set of studies; this is especially important for HCV seroconversion studies which suffer from small sample sizes and low power to examine risk factors.

Quantifying hepatitis C transmission risk using a new weighted scoring system for the Blood-Borne Virus Transmission Risk Assessment Questionnaire (BBV-TRAQ): applications for community-based HCV surveillance, education and prevention

Background

The hepatitis C virus (HCV) is a major cause of drug-related morbidity and mortality, with incidence data implicating a wide range of HCV transmission risk practices. The Blood-Borne Virus Transmission Risk Assessment Questionnaire (BBV-TRAQ) is a content valid instrument that comprehensively assesses HCV risk practices. This study examines the properties of a new weighted BBV-TRAQ designed to quantify HCV transmission risk among injecting drug users (IDU).

Methods

Analyses of cross-sectional surveys of Australian IDU (N = 450) were used to generate normative data and explore the properties of a weighted BBV-TRAQ. Items weights were assigned according to expert key informant ratings of HCV risk practices performed during the development stages of the BBV-TRAQ. A range of item weights was tested and psychometric properties explored. A weighting scheme was recommended based on the plausibility of normative subscale data in relation to research evidence and the ability of BBV-TRAQ scores to discriminate between HCV positive and negative participants.

Results

While retaining the psychometric properties of the unweighted scale and demonstrating good internal reliability. By taking into account the relative transmission risk of a broad range of putative HCV practices, the weighted BBV-TRAQ produced promising predictive validity results among IDU based on self-report HCV status, particularly among young and less experienced injectors.

Conclusion

Brief, easy to administer and score, and inexpensive to apply, the utility of the BBV-TRAQ for community based education and prevention is enhanced by the application of item weights, potentially offering a valid surrogate measure for HCV infection among IDU.

Viral hepatitis and HIV coinfection

Persons at high risk for human immunodeficiency virus (HIV) infection are also likely to be at risk for other infectious pathogens, including hepatitis B virus (HBV) or hepatitis C virus (HCV). These are bloodborne pathogens transmitted through similar routes; for example, via injection drug use (IDU), sexual contact, or from mother to child during pregnancy or birth. In some settings, the prevalence of coinfection with HBV and/or HCV is high. In the context of effective antiretroviral therapy (ART), liver disease has emerged as a major cause of morbidity and mortality in HIV-infected persons. Further, coinfection with viral hepatitis may complicate the delivery of ART by increasing the risk of drug-related hepatoxicity and impacting the selection of specific agents (e.g., those dually active against HIV and HBV). Expert guidelines developed in the United States and Europe recommend screening of all HIV-infected persons for infection with HCV and HBV and appropriate management of those found to be chronically infected. Treatment strategies for HBV infection include the use of nucleos(t)ide analogues with or without anti-HIV activity and/or peginterferon alfa (PegIFN) whereas HCV treatment is limited to the combination of PegIFN and ribavirin (RBV). Current approaches to management of HIV-infected persons coinfected with HBV or HCV are discussed in this review.

Routine practice HCV infection screening with saliva samples: multicentric study in an intravenous drug user population

OBJECTIVE

The purpose of this randomized multicentric study was to evaluate the diagnostic contribution of screening for HCV infection on saliva samples in day-to-day practice in the intravenous drug-user (IVDU) population.

METHODS

Between January and May 2004, 274 presumably HCV-negative IVDU were screened for HCV infection in 15 centers in France (median age 29 years). After centralized randomization, screening tests were performed on blood samples (arm A) or saliva samples (arm B). Screening tests were performed in 78 subjects (28%) had never been screened before and in 196 subjects (72%) who had had a negative HCV screening test on average 12 months prior to the beginning of the study. In the event of a positive saliva test for anti-HCV Ab, a serum test for anti-HCV Ab was performed. In the event of a positive serum test for anti-HCV Ab, PCR was performed on serum to measure HCV-RNA.

RESULTS

Fourteen individuals were positive for HCV RNA (7 in each arm). Six of these cases had not been detected before. In eight cases, the median time between the last negative screening test and study inclusion was 11 months (range 6-94 months).

CONCLUSIONS

Viremia tests were positive in 5% percent of the target population, although one-third of the individuals in arm A (blood samples) were not tested. The saliva test may be a useful alternative in the event of refusal of a blood test or when poor venous conditions compromise venous puncture. A confirmatory blood test still remains difficult to obtain in nearly half of patients.

Hepatitis C virus (HCV) prevalence, and injecting risk behaviour in multiple sites in England in 2004

We sought to corroborate geographical differences in hepatitis C virus (HCV) prevalence and assess whether these can be explained by differences in injecting risk behaviour. A community recruited interview survey of 1058 injecting drug users (IDU) - including a blood spot specimen for antibody testing - was undertaken in seven cities in England. HCV prevalence varied from 27% to 74% across sites (chi(2)(6) = 115.3, P < 0.001). There was a significant variation in crack-injection, prison history, injecting frequency, homelessness, groin injecting, syringe reuse and sharing between the sites. Adjustment for clustering by site and other covariates attenuated the odds ratios (OR) for most variables: e.g. crack injection changed from an unadjusted OR of >2 to an adjusted OR of 1.4 (95% CI 0.9-2.0). Remaining significant covariates included: homelessness (OR 2.2; 1.4-3.6); ever imprisonment (OR 1.7; 1.2-2.5); syringe sharing >18 months ago (OR 2.0; 1.3-3.0); injecting duration and age. Introducing site as a second level variable did not reach significance (P = 0.10). HCV prevalence among IDU reporting 'never sharing' was 48%. Geographical variation in HCV prevalence remains poorly explained, but should be the key focus of our surveillance effort. Measures of sharing and their interpretation require greater scrutiny.

Hepatitis C virus: laboratory surveillance in England and Wales, 1992-2004

Between 1992 and 2004, a total of 49,819 confirmed hepatitis C infections have been reported to the Health Protection Agency (HPA) by laboratories in England and Wales; the annual number of reports increased from 241 in 1991 to 8149 in 2004. Most reports with a known risk factor were in injecting drug users (87%, 12,438/14,221), but 71% (35,598/49,819) of the total had no reported identified risk. The age-sex distribution of the latter cases was similar to that in injecting drug users. Using names to assign ethnicity, individuals with South Asian names had an older age distribution and a different risk factor profile from non-South Asians. Using published age-specific prevalence data from 1996, it was estimated that around 28,1764 cases of hepatitis C infection exist in England and Wales, and that only 17% of these cases have been reported to the HPA. Surveillance reports continue to provide important information regarding trends in hepatitis C infection in specific risk groups.

Major decline of hepatitis C virus incidence rate over two decades in a cohort of drug users

Injecting drug users (DU) are at high risk for hepatitis C virus (HCV) and HIV infections. To examine the prevalence and incidence of these infections over a 20-year period (1985-2005), the authors evaluated 1276 DU from the Amsterdam Cohort Studies who had been tested prospectively for HIV infection and retrospectively for HCV infection. To compare HCV and HIV incidences, a smooth trend was assumed for both curves over calendar time. Risk factors for HCV seroconversion were determined using Poisson regression. Among ever-injecting DU, the prevalence of HCV antibodies was 84.5% at study entry, and 30.9% were co-infected with HIV. Their yearly HCV incidence dropped from 27.5/100 person years (PY) in the 1980s to 2/100 PY in recent years. In multivariate analyses, ever-injecting DU who currently injected and borrowed needles were at increased risk of HCV seroconversion (incidence rate ratio 29.9, 95% CI 12.6, 70.9) compared to ever-injecting DU who did not currently inject. The risk of HCV seroconversion decreased over calendar time. The HCV incidence in ever-injecting DU was on average 4.4 times the HIV incidence, a pattern seen over the entire study period. The simultaneous decline of both HCV and HIV incidence probably results from reduced risk behavior at the population level.

Health trends among drug users attending needle exchange programmes in Switzerland (1994–2000)

As a part of an assessment of the Swiss drug harm-reduction policy, cross-sectional surveys were conducted in 1994, 1996 and 2000 among attenders of all needle exchange programmes (NEP) in Switzerland to assess changes in specific aspects of their health related to drug use. Data were gathered in each NEP over one week, using a questionnaire completed partly with an interviewer and partly self administered. The questionnaire covered socio-demographic characteristics, drug consumption, risk, prevention behaviour and state of health. Over a 6-year period (1994-2000), the average age of NEP attenders rose by 4 years. The prevalence of reported HIV remained fairly stable at around 10%. Reported level of Hepatitis C prevalence was high (59%). Incidence of used injection equipment sharing during the last 6 months was low and stable (9% in 1994, 12% in 2000); however, other forms of risk behaviour linked to intravenous drug use, such as sharing spoons, cotton or water, were more frequently reported. The HIV epidemic among NEP attenders seems to be contained, but this is not the case with Hepatitis C, and more attention should be paid to its prevention.

Mayisha II: Pilot of a community-based survey of sexual attitudes and lifestyles and anonymous HIV testing within African communities in London

The pilot aim was to assess the feasibility and acceptability of undertaking anonymous HIV testing using oral fluid samples as part of a community-based survey of sexual attitudes and lifestyles of black African communities in London. The three components of the study were administered in various venues across London: (1) a cross-sectional self-completion anonymous questionnaire survey, (2) an optional oral fluid sample for anonymous HIV testing and (3) a nested in-depth interview study in a sub-set of respondents. A total of 114 black African men and women were recruited. A large number of African countries were represented among respondents from newly-migrant and well-established communities. The response rate to the oral fluid sample was high at 82% and all samples collected were of sufficient quality to be tested for HIV. In-depth interviews with respondents revealed positive views and experiences about participating in the study whilst understanding of the questionnaire was good. We therefore conclude that anonymous HIV testing as part of a community-based survey is feasible and acceptable, whilst a set of recommendations was produced to refine the survey methodology and questionnaire. Participatory research methods are essential for achieving successful community-based surveys among black Africans in Britain.

The phylogenetic analysis of hepatitis C virus isolates obtained from two Iranian carriers revealed evidence for a new subtype of HCV genotype 3

Classification of hepatitis C virus is based on phylogenetic analysis of the strains reported world wide. Different strains are classified within 6 major genotypes and several minor groups (subtypes). In addition to epidemiologic value of determining genotype/subtype of this virus, the result may change the therapeutic strategy used for a patient. During a survey on hepatitis C in Iran, we found two cases assigned as 1b genotype by PCR-RFLP on 5' UTR, but three based on core region sequencing. Fragments from 5' UTR, Core and NS5b regions were PCR-amplified and sequenced followed by phylogenetic analysis. Although the 5' UTR of this new strain is very similar to genotypes 1 and 6, analysis of core region classifies it in a separate branch of genotype 3, close to subtypes h and k. Further analysis of NS5b region put this new strain in a separate branch near other subtypes of genotype 3 and 4. These data are suggestive of a new subtype within genotype 3.

Barriers to the dissemination of four harm reduction strategies: a survey of addiction treatment providers in Ontario

A sample of service providers at addictions agencies' in Ontario were interviewed by telephone to assess attitudes toward, anticipated internal and external barriers to implementing, and expected benefits of four harm reduction strategies: needle exchange, moderate drinking goals, methadone treatment, and provision of free condoms to clients. Respondents were also asked to define harm reduction, list its most important elements, and describe what they find most troubling and most appealing about harm reduction. Attitudes toward harm reduction in general and the services provided at each agency were also assessed. Results indicated that the service providers surveyed had positive attitudes toward each of the four harm reduction strategies and harm reduction in general, and the majority of respondents were aware of the benefits associated with each strategy. Almost all of the agencies surveyed allowed for moderate drinking outcomes in the treatment of alcohol problems, and most agencies provided free condoms to clients. In terms of barriers, anticipated negative community reaction to needle exchange, methadone treatment, and free condoms was a major concern for the majority of respondents. Lack of staff, of funding, or anticipated staff resistance were also cited as potential barriers to introducing these strategies. In the case of methadone maintenance, the unavailability of a qualified physician was listed as the primary constraint. Implications for future efforts directed at encouraging the adoption of these strategies and suggestions for future research are discussed.

Prevalence of hepatitis and HIV infections and vaccination rates in patients entering the heroin-assisted treatment in Switzerland between 1994 and 2002

BACKGROUND

Hepatitis C virus (HCV) remains very prevalent in injection drug users (IDUs). In spite of recommended vaccinations against hepatitis A virus (HAV) and hepatitis B virus (HBV), many IDUs remain susceptible to HAV and HBV.

STUDY POPULATION AND METHODS

Patients entering heroin-assisted treatment between 2000 and 2002 (N = 210) were compared for infectious disease status with patients entering this treatment in 1998 (N = 243) and between 1994 and 1996 (N = 1035). Infection status was determined with the aid of questionnaires and blood tests for antibodies against HAV, HBV core antigen, HCV and HIV.

RESULTS

In the cohort 2000-2002 78.3% of the patients were HCV positive, 53.3% were HBV positive, 41.2% were HAV positive and 12.6% were HIV positive. In comparison to the cohorts entering the heroin- assisted treatment at an earlier time, there was a significant reduction of HBV and HAV infections, but not of HCV and HIV infections. 15.6% of the patients entering between 2000 and 2002 were vaccinated against HBV and 10.3% against HAV. 31.1% of patients at entrance were susceptible for HBV and 48.5% for HAV. In comparison to patients entering treatment in 1998 there was no significant increase in patients who were vaccinated against HBV.

CONCLUSIONS

This data illustrates the need for improving HCV prevention and more consequent vaccination against HBV and HAV in IDUs.

Estimating adult HIV prevalence in the UK in 2003: the direct method of estimation

BACKGROUND

Estimates of the total number of prevalent HIV infections attributable to the major routes of infection make an important contribution to public health policy, as they are used for planning services.

METHODS

In the UK, estimates were derived through the "direct method" which estimated the total number of diagnosed and undiagnosed HIV infections in the population. The direct method has been improved over a number of years since first used in 1994, as further data became available such as the inclusion of newly available behavioural survey data both from the National Survey of Sexual Attitudes and Lifestyles (Natsal 2000) and community surveys of men who have sex with men (MSM). These data were used to re-estimate numbers of people unaware of their infection and provided ethnic breakdowns within behavioural categories. The total population was divided into 10 mutually exclusive behavioural categories relevant to HIV risk in the UK-for example, MSM and injecting drug users. Estimates of the population size within each group were derived from Natsal 2000 and National Statistics mid-year population estimates. The total number of undiagnosed HIV infections was calculated by multiplying the undiagnosed HIV prevalence for each group, derived from the Unlinked Anonymous HIV Prevalence Monitoring Programme surveys (UAPMP), by the population size. These estimates were then added to the prevalent diagnosed HIV infections within each group derived from the national census of diagnosed HIV infections, the Survey of Prevalent HIV Infections Diagnosed (SOPHID). The estimates were then adjusted to include all adults in the UK. Because undiagnosed HIV prevalence estimates were not available for each of the behavioural categories, the UAPMP prevalence estimates were adjusted using available data to provide the best estimates for each group.

RESULTS

It is estimated that 53,000 individuals are infected with HIV in the UK in 2003, of whom 27% were unaware of their infection. Of the total of 53,000, an estimated 26,000 were among heterosexually infected and 24,500 among MSM.

CONCLUSION

The direct method uses an explicit framework and data from different components of the HIV surveillance system to estimate HIV prevalence in the UK, allowing for a comprehensive picture of the epidemic.

Modelling the force of infection for hepatitis B and hepatitis C in injecting drug users in England and Wales

Background

Injecting drug use is a key risk factor, for several infections of public health importance, especially hepatitis B (HBV) and hepatitis C (HCV). In England and Wales, where less than 1% of the population are likely to be injecting drug users (IDUs), approximately 38% of laboratory reports of HBV, and 95% of HCV reports are attributed to injecting drug use.

Methods

Voluntary unlinked anonymous surveys have been performed on IDUs in contact with specialist agencies throughout England and Wales. Since 1990 more than 20,000 saliva samples from current IDUs have been tested for markers of infection for HBV, HCV testing has been included since 1998. The analysis here considers those IDUs tested for HBV and HCV (n = 5,682) from 1998–2003. This study derives maximum likelihood estimates of the force of infection (the rate at which susceptible IDUs acquire infection) for HBV and HCV in the IDU population and their trends over time and injecting career length. The presence of individual heterogeneity of risk behaviour and background HBV prevalence due to routes of transmission other than injecting are also considered.

Results

For both HBV and HCV, IDUs are at greatest risk from infection in their first year of injecting (Forces of infection in new initiates 1999–2003: HBV = 0.1076 95% C.I: 0.0840–0.1327 HCV = 0.1608 95% C.I: 0.1314–0.1942) compared to experienced IDUs (Force of infection in experienced IDUs 1999–2003: HBV = 0.0353 95% C.I: 0.0198–0.0596, HCV = 0.0526 95% C.I: 0.0310–0.0863) although independently of this there is evidence of heterogeneity of risk behaviour with a small number of IDUs at increased risk of infection. No trends in the FOI over time were detected. There was only limited evidence of background HBV infection due to factors other than injecting.

Conclusion

The models highlight the need to increase interventions that target new initiates to injecting to reduce the transmission of blood-borne viruses. Although from the evidence here, identification of those individuals that engage in heightened at-risk behaviour may also help in planning effective interventions. The data and methods described here may provide a baseline for monitoring the success of public health interventions.

Variation in hepatitis C services may lead to inequity of heath-care provision: a survey of the organisation and delivery of services in the United Kingdom

BACKGROUND

Chronic hepatitis C infection (CHC) is a major healthcare problem. Effective anti-viral therapy is available. To maximise population effectiveness, co-ordinated services for detection and management of patients with CHC are required. There is a need to determine patterns of healthcare delivery to plan improvements. A study was conducted to determine workload, configuration and care processes of current UK services available to manage patients with CHC.

METHODS

A cross-sectional questionnaire survey of consultant members of British Association for the Study of the Liver (n = 53), Infectious Disease consultants (n = 43), and a 1 in 5 sample of Genito-Urinary Medicine (n = 48) and gastroenterologists (n = 200).

RESULTS

Response rate was 70%. 40% of respondents provided a comprehensive service (included treatment and follow-up): speciality of clinical leads identified as Hepatology (37%); Gastroenterology (47%); and Infectious Disease (16%). The estimated number of patients managed by respondents was about 23,000 with an upward trend over the previous 3 years. There was variation between comprehensive service providers, including unit size, eligibility criteria for treatment, and drug regimes. Key barriers to quality of care identified were staffing capacity, funding of treatment and patient non-attendance. Most English strategic health authorities had at least one comprehensive service provider.

CONCLUSION

There was significant variation in all aspects of the patient pathway which may contribute to inequity of health care provision. Services need to be expanded to form geographical clinical networks, and properly resourced to ensure greater uptake and more equitable delivery of services if the future burden of chronic liver disease is to be reduced.

Prevalence of, and risk factors for, hepatitis C virus infection among recent initiates to injecting in London and Glasgow: cross sectional analysis

Our aim was to compare the prevalence of antibody to hepatitis C virus (anti-HCV) among recently initiated injecting drug users (IDUs) in London and Glasgow, and to identify risk factors which could explain differences in prevalence between the cities. Complementary studies of community recruited IDUs who had initiated injection drug use since 1996 were conducted during 2001-2002. Data on HCV risk behaviours were gathered using structured questionnaires with identical core questions and respondents were asked to provide an oral fluid specimen which was tested anonymously for anti-HCV but was linked to the questionnaire. Sensitivities of the anti-HCV assays for oral fluid were 92-96%. Prevalence of anti-HCV was 35% (122/354) in London and 57% (207/366) in Glasgow (P < 0.001). Multifactorially, factors significantly associated with raised odds of anti-HCV positivity were increasing length of injecting career, daily injection, polydrug use, having had a needlestick injury, and having served a prison sentence. In addition lower odds of anti-HCV positivity were associated with non-injection use of crack cocaine and recruitment from drug agencies. After adjustment for these factors, the increased odds of anti-HCV associated with being a Glasgow IDU were diminished but remained significant. HCV continues to be transmitted among the IDU population of both cities at high rates despite the availability of syringe exchange and methadone maintenance. Effectiveness of harm reduction interventions may be compromised by inadequate coverage and failure to reduce sufficiently the frequency of sharing different types of injecting equipment, as well as the high background prevalence of HCV, and its high infectivity. Comprehensive action is urgently required to reduce the incidence of HCV among injectors.

HIV/hepatitis C virus co-infection in drug users: risk behavior and prevention

Studies of HIV-positive patients have consistently shown that drug users, in particular injection drug users (IDU), are far more likely to have hepatitis C virus (HCV) infection than other patient groups. HIV incidence and prevalence in IDU has declined in recent years, but HCV remains endemic in this population. HCV antibody prevalence among non-injection users of drugs such as heroin and cocaine is between 5 and 30%, although there are scant data on specific transmission risk behavior. The control of HIV/HCV co-infection must address HCV prevention. Epidemiological studies have suggested that HCV prevalence in IDU is subject to various influences, some of which may be modifiable by interventions. However, studies have not shown consistent effects of various prevention strategies on HCV transmission, including studies of HCV screening and education, drug treatment or needle exchange. Although some large cross-sectional studies in regions where needle exchange is available to a large number of drug injectors have reported declining HCV prevalence, the scale of services needed is a matter of considerable debate and has not been systematically quantified. Priorities for research related to the prevention of HIV/HCV co-infection should include estimating the effect on disease occurrence of eliminating specific risk factors, and specifying the level of resources needed to alter HCV incidence.

Reductions in hepatitis C virus and HIV infections among injecting drug users in New York City, 1990-2001

OBJECTIVE

To assess trends in HIV, hepatitis C virus (HCV) and HIV/HCV infection among injecting drug users (IDU) from 1990 to 2001 in New York City. The 1990-2001 time period included a very large expansion of syringe exchange in New York City, from 250,000 to 3,000,000 syringes exchanged annually.

METHODS

Cross-sectional seroprevalence surveys of IDU entering drug abuse treatment in New York City, with sample sizes for HCV of 72 in 1990-1991 and 412 in 2000-2001. A structured risk behavior questionnaire was administered, and HIV and HCV testing were conducted. HCV testing was performed on de-linked stored serum samples.

RESULTS

Over the 1990-2001 period, HIV prevalence declined from 54 to 13%. HCV prevalence declined from 80 to 59% among HIV-seronegative individuals, and from 90 to 63% overall. The estimated HCV incidence in 2000-2001 among new injectors was 18 per 100 person-years at risk.

CONCLUSIONS

The large-scale expansion of syringe exchange was temporally associated with large reductions in both HIV and HCV prevalence. The prevalence and incidence of HCV, however, still remain at high levels among IDU in New York City.

HIV prevalence among injecting drug users in England and Wales 1990 to 2003: evidence for increased transmission in recent years

OBJECTIVE

To describe trends in HIV prevalence among injecting drug users in England and Wales between 1990 and 2003.

METHODS

Analysis of surveillance data from voluntary unlinked anonymous cross-sectional surveys collecting oral fluid samples and behavioural information from injecting drug users recruited from both drug agency (n = 24,304) and community settings (n = 3628).

RESULTS

HIV prevalence in England and Wales declined from 5.9% in 1990 to 0.6% in 1996 and then remained stable until 1999, after which it increased to 1.4% in 2003. Few HIV infections were detected among short-term injectors between 1994 and 1999, but in recent years prevalence among this group has increased. Other factors associated with higher odds of HIV infection were being recruited in London and from community settings, and ever having had a voluntary confidential HIV test. Incidence estimated through a force of infection model was 2.8% per annum among those injecting for less than a year in London between 1998 and 2003.

CONCLUSIONS

These data suggest that incidence and prevalence of HIV may have increased, whereas other indicators suggest an increase in risk behaviour. It is critical that harm reduction measures are reinvigorated, and evolve in response to changes in drug use risk behaviours and policy.

"When you're using gear you put HIV to the back of your mind and forget about it": constructs of risk

This article presents findings from a qualitative study concerning drug injectors' constructs of human immunodeficiency virus (HIV) risk behavior. Analysis of data obtained from in-depth interviews (some with a vignette) of drug injectors found that when individuals needed an injection of drugs and were experiencing drug withdrawal they were more likely to take drug injecting risks. This was often discussed within an overall preoccupation with drug use. The substantive focus of the analysis goes on to explore drug injectors' desire to think about the consequences of HIV risk behavior at a later point in time. These exploratory findings highlight how further research needs to be undertaken in order to improve understanding of the temporal issues concerning drug injecting HIV risk behavior.

Innovation, diffusion and safety of a medical technology: a review of the literature on injection practices

The rapid uptake of the hypodermic syringe as a medical technology by physicians in Europe and America since its introduction in the middle of the 19th century has led to a level of medical and public acceptance seldom reached by other therapeutic techniques. Presently, the developed world has clear guidelines regarding injection use and safety; in contrast, developing countries are facing the brunt of risks associated with the use of this technology, which was introduced into their societies during the early 20th century. There is now a popular demand for injections, and an alarming number of unnecessary and unsafe injections are being administered. The problem of unsafe injections is not restricted to curative injections, but includes immunizations too. The association of unsafe injections and infection transmission is quite clear, and there is an urgent need to reduce the number of required injections and make them safe. An understanding of the determinants of current injection practices in the socio-cultural-economic context is necessary in order to plan relevant and effective interventions.

Preventing hepatitis C: 'common sense', 'the bug' and other perspectives from the risk narratives of people who inject drugs

There is little published research about how people who inject drugs are responding to the hepatitis C epidemic. This study seeks to address the prevention of hepatitis C using qualitative interviews with people who inject drugs in London. We explored narratives about risk reduction and hepatitis C in the social and historical context of other risks such as HIV, vein damage and overdose. Themes of the narratives included: the importance of autonomy in the acquisition of safer injecting skills; that safer injection was regarded as 'common sense', normalised and predicated on the risk of HIV; that hepatitis C risk was relativised with HIV risk and thereby seen as less important; and that hepatitis C infection was also seen as unavoidable. These narrative forms represent significant challenges for the management of the hepatitis C epidemic, both in terms of the existing risk reduction efforts designed for HIV and in terms of the articulation of risk reduction for injectors with general public health policy.

Management of hepatitis C in active drugs users: experience of an addiction care hepatology unit

OBJECTIVE

Recent guidelines on the management of patients chronic hepatitis C virus (HCV) infection recommend the same anti-HCV therapy for active intravenous drug users and other patients, however some physicians are reluctant to treat active drug users. The aim of this study was to compare hepatitis C management practices and clinical outcome after treatment between active intravenous drug users and other patients.

METHODS

Four hundred and thirty-five naive HCV seropositive patients were recruited from 1990 to 2000 and followed up for a mean period of 2.5 years (SD 1 Year). At the beginning of the study, 116 of the patients were active intravenous drug users. Social, clinical, biological and histological data were collected. The different steps of HCV management and responses to treatment were compared between active intravenous drug users and other patients.

RESULTS

There was no statistically significant difference in HCV management practices and compliance between active intravenous drug users and other patients: search for viral RNA (85% versus 67%), liver biopsy performed when indicated (82% versus 87%), initiation of anti-HCV treatment (33.6% versus 43.2%), loss to follow up during treatment (24% vs 16%). The rate of sustained viral response was not significantly different between active intravenous drug users and other patients (28% versus 21%). At multivariate analysis, factors independently associated with sustained viral response were female gender (OR=5.6 [1.02-41.2]), genotype 3 (OR=29.7 [1.4-61.7]), low viral load (OR=33.3 [2.25-100]), low fibrosis score (OR=1.4 [1.0-2.0]), elevated transaminase level (OR=12.7 [0.9-97.2]), and bitherapy protocol (OR=10 [1.18-85.3]).

CONCLUSION

This study illustrates that active intravenous drug use does not affect either patient compliance with proposed management or viral response to treatment, but pluridisciplinary care should focus both on drug addiction and HCV infection.

Failure to diagnose recent hepatitis C virus infections in London injecting drug users

Hepatitis C virus (HCV) infection results in chronic liver disease in a substantial proportion of those infected. Most new cases of HCV infection in the UK are associated with intravenous drug use. It is important to identify these infections because of the implications for the future health of the individuals concerned and for the control of further spread of infection. However, as hepatitis C infection is characterised by a relatively long asymptomatic period of seronegative viraemia, a laboratory diagnostic protocol that does not test HCV seronegative samples for the presence of HCV RNA may wrongly designate HCV viraemic seronegative individuals as uninfected. Amongst 424 injecting drug users whose serum was sent to our diagnostic laboratory for "HCV screening" over a 14-month period, the prevalence of HCV seropositivity was 48.4%. We retrospectively identified seven individuals for whom there was evidence of recent acquisition of HCV infection. Three of these infections were identified using our routine diagnostic protocol: testing for the presence of HCV-specific antibody and performing HCV RNA testing only on seropositive and seroindeterminate specimens. However, four cases were only identified by HCV RNA testing of HCV seronegative serum. On the basis of these observations, we estimate the incidence of HCV infection amongst London injecting drug users as being 14.3 per 100 person-years. We advocate that all HCV seronegative blood samples obtained from injecting drug users should be tested for the presence of HCV RNA, and suggest that this could be done efficiently by nucleic acid testing the specimens in small pools. .

Hepatitis C and its risk management among drug injectors in London: renewing harm reduction in the context of uncertainty

AIM

Recognizing the dearth of qualitative research on hepatitis C virus (HCV) infection associated with injecting drug use in the UK, this paper summarizes qualitative insights from a study exploring the social relations of HCV risk management among drug injectors in London.

METHOD

Adopting an inductive approach to data collection and analysis, 59 depth tape-recorded qualitative interviews were undertaken in 2001 with drug injectors recruited via drug user networks.

RESULTS

While access to injecting equipment was reportedly good, needle and syringe sharing continued in exceptional circumstances and in the context of 'trust relationships'. Analyses of drug injectors' accounts of variations of 'I never share' showed that this construction denoted less a descriptor of actual risk behaviour than presentation of perceived risk status. Paraphernalia sharing, including spoons and filters, was common. There was much confusion and uncertainty concerning HCV knowledge, including its medical and transmission risks. Injectors were aware of the provisionality and partiality of their HCV knowledge. Confusion also surrounded the meaning of HCV antibody test results, with some feeling that their positive diagnosis had been 'trivialized' by their experiences of HCV testing. Injectors tended to make sense of HCV risk in relation to HIV. With most viewing HCV prevalence as high and HCV transmission as an inevitable consequence of injecting, HCV risk was perceived as ubiquitous and unavoidable.

CONCLUSIONS

There is an urgent need to renew UK policies of harm reduction in order to support perceptions that HCV is avoidable and preventable.