How effective have harm reduction interventions been in reduction of Hepatitis C incidence among Injecting Drug Users in the UK?

1.0 Introduction
The prevalence of Hepatitis C (HCV) internationally is largely unknown mainly due to the fact that most individuals have no symptoms in the early stages of the infection. The WHO estimates the figure at 170 million people infected with HCV and it is estimated that approximately 3-4 million people are newly infected each year . Injecting drug users (IDUs) are at greatest risk from HCV through the sharing of injecting paraphernalia.

In the UK estimates from the Health Protection Agency (HPA) data has the number of people chronically infected with HCV at 216000 of which 90% are attributable to IDUs with over 40% of the IDU population being HCV antibody positive . Some estimates of numbers with HCV in the UK suggest about 500000 .

In 2010, new HCV infections diagnosed in the UK was 10,381 of which there were 7384, 106, 2129, and 312 in England, Northern Ireland, Scotland and Wales respectively . There appears to be higher rate of transmission among IDU now than a decade ago; 23% compared to 12% in 2000
Although UK is classified as a low prevalence country for HCV; The HCV poses numerous challenges for public health in terms of potentially preventable mortality and morbidity. According to NICE guidance, it would cost the NHS about £1.6 billion to treat all Hepatitis C patients. The cost therefore of failing to diagnose and treat existing patients could be approximately £4-£8 billion over the next decade

As the most infected in the UK are IDUs, the strategy is to target this risk group by making them more aware, offering proactive testing to ensure that those who are undiagnosed are and get necessary treatment early. It is essential to have in place robust surveillance systems and in the UK the harm reduction approach with IDUs has been adopted as this has proved to be effective in reducing the incidence of HCV.

Aim of Essay
This essay sought to review the evidence on the effectiveness of harm reduction interventions in the prevention of hepatitis C virus (HCV) among drug users (IDUs) in the UK. The intervention assessed is Needle Exchange Programmes (NEPs). The review has looked at a number of research using mixed methodology to assess this impact of NEPS. The research for NEPs impact on HCV in the UK is limited and evidence of impact were mainly from surveys and collated data by WHO and HPA (Health Protection Agency) There were also data by the National Treatment Agency (NTA) from which I was able to extract current figures. A majority of the research were conducted outside the UK; mainly in the USA and Europe and Australia. Even these in most cases assessed impact on HIV primarily.

2.0 Transmission of HCV
The HCV is carried in the blood and has been detected in other body fluids such as urine and saliva. However, blood has been identified as main transmission route . The major route of HCV transmission in the UK is believed to be by sharing equipment for injecting drug use, mainly via blood-contaminated needles. Spoons, water and filters may also be routes of infection. It has also been reported that sharing pipes for smoking and snorting paraphernalia can transmit HCV.
Prior to 1991, there was significant risk from blood transfusion. Nowadays screening of all blood donations is in place and a heat treatment process is applied to blood to protect against HCV .
Other transmission routes include tattoos, body piercing and the use of unsterile equipment. Although no evidence exists to support transmission from contact such as hugging, holding hands and kissing, some exists that a small amount may be transmitted via personal toiletry items following blood contamination.
Also of note is transmission via healthcare workers following needle stick injury.

3.0 Surveillance
Although the UK is classified as a low prevalence country for HCV, there exist numerous challenges for public health in terms of preventable mortality and morbidity. In the UK, the HPA is responsible for all surveillance and follow-up. Surveillance is essential in order to target prevention and control activities. It is also essential once detection has been established for there to be a process of investigation and follow up to determine risk factors. Of significance is the role of detecting outbreak, identifying contacts that need to be vaccinated to prevent any further transmission.

HCV is a statutory notifiable infection. Laboratories are required to notify the HPA when they diagnose cases of HCV. There were a total of 2586 laboratory reports of hepatitis C virus reported to the HPA between January and March 2011 . Standards for surveillance for HCV in the UK are constantly being reviewed and the current standards were developed in 2006 due to incidents of error in lab reporting and they were revised in 2011 . Where cases of acute cases are diagnosed these have to be reported to the local health authority for investigation .

Diagnosing HCV infection is pretty straight forward as chronic liver disease is probably enough to diagnose an infection. To confirm the diagnosis the entire lab then has to do is to confirm is an antibody test. Patients with suspected HCV infection are tested for anti-HCV by an up to date ELISA test . Matching sentinel surveillance by the HPA with information collated from the NTA allows for matching of the risk factor association between HCV and drug injecting.

4.0 HCV Testing
Many cases of HCV remain undiagnosed . HCV testing is not universally offered and whether an individual is going to be offered a test will differ from GP to GP, with the exception of drug users for whom the National Treatment Agency (NTA) has set targets for treatment services to offer HCV tests and immunization for HBV to 100% of users . Long term infection with HCV is associated with serious liver disease and death and hence the key aim in any public health work with HCV is to prevent new infections, testing and treating those who have been diagnosed .

For most people HCV is curable. NICE guidelines are in place on how therapy should be offered . Despite user’s awareness of campaigns such as ” harm reduction works” , treatment uptake in the UK remains very low. This is may be due to fact that HCV screenings are risk based and targets very few people in the population to give confidence that we are aware of the true extent of the problem. Unlike Hepatitis A and B there is no vaccine available for HCV. The protocol is generally to target certain at risk groups and offer them an intervention. As there is no vaccine the aim is therefore primary prevention (prevention of new infections), Secondary prevention looks at treatment of those infected while tertiary prevention focuses on reducing complications in those on treatment.

With IDU the primary interventions are harm reduction such as NEPs, Opiate substitution therapy, behavioural approaches and consumption rooms. For the rest of this discussion, I will look at NEPs

5.0 The Controversy that is Harm Reduction
Few treatment strategy terms evoke as much controversy as harm reduction. “Harm reduction refers to policies, programmes and practices that aim primarily to reduce the adverse health, social and economic consequences of the use of legal and illegal psychoactive drugs without necessarily reducing drug consumption” as for reducing HCV transmission through injecting drug use.

Harm Reduction principle of dealing with substance dependence sits well with most medical clinicians in the work of Addiction as it encompasses the areas of public health and principles of palliative care, where palliative care is taken in its broad sense of relieving, alleviating or easing a condition without curing. Harm reduction programmes work on the premise that those engaged in high risk behaviour cannot abstain. The key harm reduction strategies are opioid substitute therapy (methadone or bupremorphine therapy) and needle exchange programmes (NEPs). Why then do people frown at harm reduction when applied to substance misuse treatment? NEPs have been controversial from their inception. The controversy around NEPs is that they can be viewed as a policy of both directly supporting an illegal activity but also as a policy to reduce harm among marginalised people at risk of developing serious infection
I will mention briefly Drug Consumption Rooms (DCRs) also known as safe injecting facilities. These were developed around the premise that IDUs need a place which is private to inject as part of a health promotion campaign , to encourage safer injecting techniques and for them to be given information and advice. Very little evidence exist for their effectiveness as there have not been any substantial research to check their efficacy.
6.0 Needle Exchange Programmes
Needle exchange programmes were instituted in the UK in 1985 in an attempt to reduce HIV infections. Among the first countries to adopt NEPs were Netherlands and UK followed by Australia and they did so even before the evidence for their effectiveness was confirmed as effective . Transmission risks vary. Compared to HIV infection, HCV infection is characterised by relatively high concentrations of virus in the blood, not only during the primary infection phase, but also in those who become chronically infected . This is thought to lead to high transmission rates upon exposure to HCV when infected and non-infected individuals share needles, syringes or other drug preparation equipment. HCV prevalence normally exceeds HIV prevalence in user communities, and HCV epidemics often precede HIV epidemics among people who inject drugs. The higher transmission risk may also explain why HCV is more difficult to limit through the application of single interventions, and why higher intervention coverage may be needed to reduce HCV rates at population level .

In the UK these schemes provide sterile syringes and needles as well as other injecting paraphernalia. In the UK most of the NEPs are commissioned to voluntary organisations who work in collaboration with NHS specialist services to deliver a comprehensive drug treatment package to cover the functions mentioned below. A number of pharmacies also run NEPs and these have been shown to be effective with pharmacies providing at least 80% of NEPs in England

The principle is that from these functions IDUs will not have the need to share needles and in so doing will reduce their risk of HCV transmission. They will commence their treatment journey if they had not come in contact previously and will in the long term address their drug use and eventually stop using drugs and ultimately injecting. By attending a NEP, the IDU will be offered BBV testing and once their status is achieved by offered relevant counselling and treatment if this is indicated.
The rationale behind the strategy is based on the premise that it is cheaper to prevent infection than treatment of the condition and that this cost benefit ratio can be fully realised by ensuring that NEPs are provided in all areas where drugs and particularly injecting drug use is a problem.
National Treatment Agency (NTA) data shows that needle sharing has declined from 33% of injectors in 1999 to 19% by 2009 and this has been closely related to expansion of NEPs .
7.0 The Evidence
Early studies give a mixed picture of the effectiveness of NEPs. A series of large observational studies conducted in Scotland in the mid-1990s compared prevalence of anti-HCV for the periods before during and after introduction of NEPs. Results showed a statistically significant reduction in anti-HCV prevalence in the early 1990s (shortly after the introduction of NEPs). Reduction was greatest in the under 25s. However, evaluation in the late 1990s showed that the declining trend in overall prevalence did not continue. There was only a reduction for those aged over 25. The authors concluded that the incidence of HCV decreased during the 1990s, but prevalence remained high The latter reported a reduction in anti-HCV prevalence after 1991 (when both needles and syringes were available) compared to 1988–1990 (when needles but not syringes were available) compared to before needle and syringe exchange in 1987.
To determine the prevalence of HCV antibodies among injecting drug users and to gauge the effectiveness of NEPs in preventing the transmission of HCV infection: A cross-sectional survey of IDUs in Glasgow following the introduction of NEPs between 1990 and 1994 showed the prevalence of HCV among injectors in Glasgow has decreased during the era of NEPs. However, there is evidence to suggest that the incidence of infection remains high. Since the prevalence of HCV among the city's injecting population is extremely high, on-going transmission is inevitable unless more effective interventions are identified and implemented. There was also a correlation between number of years one had been injecting and HCV infection. Those who had started injecting after introduction NEPs were significantly less likely to test HCV positive than those who had been injecting prior to NEPs .
The high levels of HCV infection IDU is compounded by the fact that many of those who have contracted HCV through injecting drug use are unaware of their infection status giving credence to the fact that early initiation of prevention measures is important.
In addition to high levels of HCV, IDUs usually have a comorbidity of infection’s including hepatitis B or HIV. Having concurrent hepatitis infections greatly increases the risk of death due to sudden liver failure. Levels of hepatitis B antibodies are often very high among injectors but prevalence varies It is important therefore that HCV testing be offered as part of a comprehensive NEPs programme together with Hepatitis A and B vaccination
Recent research has produced similarly inclusive results.
A systematic review by Palmateer and colleagues looked at the effectiveness of NEPs in preventing HCV and HIV among IDUs and concluded that there was no evidence that NEPs were effectiveness in preventing HCV transmission .
The same team conducted a survey, to look at the impact of NEPs on the incidence of HCV among IDUs in the UK between 2001 and 2009, and a sample group of 2986 IDUs . The findings from this were significant. The team reported that full harm reduction; that is a combination of opiate substitute (OST) and NEPs had the effect of reducing HCV infections by 80% and needle sharing by 48%. Of significance was the reported reduction in injecting episodes which they reported as an average of 20.8 injections a month. They concluded that harm reduction substantially reduces risk of HCV transmission. As with all studies, limitations particularly of confounding exist, age, housing status, other interventions like counselling. The role of counselling and HCV testing are not adequately accounted for in these studies supporting NEPs . However. Admittedly these confounders exist but the evidence for counselling and HCV testing
The evidence for the effect of opiate substitution therapy on reducing HCV incidence has been harder to determine, mainly due to the fact that HCV is more easily transmitted through injecting and, probably, shared injecting equipment , and to the much higher baseline prevalence levels among populations of people who inject drugs across Europe, constituting a reservoir of infection risk. However, recent data including community-based cohort studies of HCV incidence among drug users, suggest a strong positive impact of OST on preventing HCV infections. These studies point to higher benefits among those in continuous OS compared to those with interrupted OST; to a protective effect of methadone maintenance treatment against both primary and secondary HIV and HCV infection; and to ‘dose-response’ effects of OST, with those in treatment longer having lower HCV incidence rates.
8.0 Conclusions
There has been difficulty in quantifying the direct effect of NEPs alone on HCV, since it may be their interaction with other interventions, or the effect of secondary exchange (users obtaining needles and distributing to their friends) that has impact on the current reductions . The limitations of observational research make it difficult to mitigate against selection bias toward the most high-risk users into NEPs. This has occasionally fuelled a debate as to whether needle exchanges cause an increase in blood-borne viruses. The international debate was perhaps at its most contentious following an outbreak of HIV in Vancouver, Canada in 1994, five years after the introduction of a NEP . In same city Schecheter and colleagues found no difference in HIV incidences between frequent attenders and infrequent . On a more sombre note the evidence in the UK shows that number of new infections of HCV exceeds that of HIV with incident rates of 41.8 per 100 person years for HCV compared to 3.4 for HIV .
What is clear though is that the current action in the UK does not go far enough given the scale of damage caused by HCV.
It would be easy to just take evidence from the HIV studies and apply them to HCV to make a case for NEPs in HCV intervention; it is important to acknowledge that the two viruses have responded differently to NEPs. Similarly policy makers would be doing IDUs and those directly affected by them a disfavour if they ignored this evidence which supports that NEPs are effective in reducing infections and in countries where they have been introduced such as the UK, Sweden, USA, the HIV epidemic has been greatly impacted. However there just does not seem to be the same political will for action on HCV. Given the comorbidity of HCV and in absence of any other intervention, public health interventions most continue to reduce syringe sharing amongst all IDUS and also look to other interventions.
The effective of NEP have been demonstrated but given the public health implication of HCV and the incidence of HCV prevalence among IDUs, further research is required accounting more for the confounders of HCV and IDU such as testing and counselling as well as coverage.
Given the evidence of the effectiveness of NEP, countries that are facing or are threatened by an HCV epidemic among IDU need to start implementing NEPs or where they have started to expand these. It is also important that where NEPs are implemented there is no restriction placed on how many needles and syringes an IDU can have.

9.0 References

Holmberg SD, et al "The growing burden of mortality associated with viral hepatitis in the United States, 1999 - 2007" Hepatology 2011; 54(4): Abstract 243

WHO Hepatitis C factsheet. Geneva 2011 ((http://www.who.int/mediacentre/factsheets/fs164/en/index.html) Accessed and downloaded 20/04/2011

Hepatitis C in the UK; 2011 Report http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1309969906418 Accessed and downloaded 24/04/2011

Hepatitis C in the UK; 2011 Report http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1309969906418 Accessed and downloaded 24/04/2011

Losing the fight against hepatitis C. London: The Hepatitis C Trust and the University of Southampton, 2005. http://www.hepctrust.org.uk/Resources/HepC/Migrated%20Resources/Documents/Other/213_The%20UK%20vs.%20Europe.pdf Accessed on-line 18/05/2011

Hepatitis C in the UK; 2011 Report http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1309969906418 Accessed on-line 24/05/2012

Shooting up Infections among people who inject drugs in the UK 2010 An update: November 2011 http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1195733837406 Accessed on-line 20/04/2012

Ramsay ME, Balogun MA, Collins M, Balraj V. Laboratory surveillance of hepatitis C virus infection in England and Wales: 1992 to 1996. Commun Dis Public Health 1998; 1(2): 89-94.
15. Cook PA, McVeigh J, Syed Q, Mutton K, Bellis M. Predictors of hepatitis B and C Health Protection Report.Volume 4 Number 34 Published 26 August 2011 http://www.hpa.org.uk/hpr/archives/2011/hpr3411.pdf Accessed on-line 24/05/2012 Van der Poel CL, Cuypers HT, Reesink HW. Hepatitis C virus six years on. The Lancet 1994; 344: 1475–9. A Judd, M Hickman, S Jones, et al Incidence of hepatitis C virus and HIV among new injecting drug users in London: prospective cohort study–2005 BMJ 330;24–25.

Health Protection Report.Volume 4 Number 34 Published 26 August2011 http://www.hpa.org.uk/hpr/archives/2011/hpr3411.pdf Accessed on-line 24/05/2012 Wright NMJ, Millson CE, Tompkins CNE (2005). What is the evidence for the effectiveness of interventions to reduce hepatitis C infection and the associated morbidity? Copenhagen, WHO Regional Office for Europe
(Health Evidence Network report; http://www.euro.who.int/document/E86159.pdf, accessed 05/03/2012.

Hawker J., Begg N., Blair I., Reintjes R., Weinberg J., Ekdahl K.(2012)
Communicable Disease Control and Health Protection Handbook. 3rd Edition. Pages 133-136 National Institutefor Clinical Excellence (NICE) Clinical guidelines on the management of hepatitis C . 2006 http://www.nice.org.uk/TA106 Accessed 20/04/2012

Health Protection Report.Volume 4 Number 34 Published 26 August 2011 http://www.hpa.org.uk/hpr/archives/2011/hpr3411.pdf Accessed on-line 24/05/2012

National Treatment Agency (2010) Injecting drug Use in England: A Declining Trend http://www.nta.nhs.uk/uploads/injectingreportnov2010finala.pdf

International Harm Reduction Development Program, Open Society Institute (2008, March) 'Harm Reduction Developments 2008: Countries with Injection-Driven HIV Epidemics'

National Institutefor Clinical Excellence (NICE) Clinical guidelines on the management of hepatitis C . 2006 http://www.nice.org.uk/TA106 Accessed 20/04/2012

http://www.harmreductionworks.org.uk/

. International Harm Reduction Policy (2010). Human Rights and Drug Policy: Harm Reduction http://www.ihra.net/files/2010/11/01/IHRA_Briefing_1.pdf Stimson, G.V. (1989). Syringe-exchange programmes for injecting drug users. AIDS, 3(5):253-260 (1989). RA 644 .A25 S74 1989

European Centre for Disease Prevention and Control and European Monitoring Centre for Drugs and Drug Addiction. Prevention and control of infectious diseases among people who inject drugs. Stockholm:
ECDC; 2011. Stockholm, October http://ecdc.europa.eu/en/publications/Publications/111012_Guidance_ECDC-EMCDDA.pdf Accessed and downloaded on 15/05/2012

. Jarlais D., et al (2005, 19th October), ‘Reductions in hepatitis C virus and HIV infections among injecting drug users in New York City, 1990 – 2001’, AIDS 2005 19(3)

National Treatment Agency (2006) Findings of a survey of needle exchanges in England http://www.smmgp.org.uk/download/rcgp-certificates/cert04/cert04-p01-d03.pdf Accessed 05/05/2012

Turner K M The impact of needle and syringe provision and opiate substitution therapy on the incidence of hepatitis C virus in injecting drug users: Pooling of UK evidence. National Treatment Agency (2010) Injecting drug Use in England: A Declining Trend http://www.nta.nhs.uk/uploads/injectingreportnov2010finala.pdf

Taylor A, Goldberg D, Hutchinson S, Cameron S, Gore SM, McMenamin J, Green S, Pithie A, Fox R. Prevalence of hepatitis C virus infection among injecting drug users in Glasgow 1990-1996: are current harm reduction strategies working? J Infect. 2000 Mar;40(2):176-83.

Taylor A, Goldberg D, Hutchinson S, Cameron S, Gore SM, McMenamin J, Green S, Pithie A, Fox R. Prevalence of hepatitis C virus infection among injecting drug users in Glasgow 1990-1996: are current harm reduction strategies working? J Infect. 2000 Mar;40(2):176-83.

Palmateer N., Kimber J., Hickman M., Hutchinson S., Rhodes T., Goldberg D. (2010) Evidence for the effectiveness of sterile injecting equipment provision in preventing hepatitis C and human immunodeficiency virus transmission among injecting drug users: a review of reviews. Addiction 105: 844–59. http://onlinelibrary.wiley.com/doi/10.1111/j.1360-0443.2009.02888.x/full Accessed on-line 24/11/2011

Turner KM, Hutchinson S, Vickerman P, Hope V, Craine N, Palmateer N, May M, Taylor A, De Angelis D, Cameron S, Parry J, Lyons M, Goldberg D, Allen E, Hickman M. The impact of needle and syringe provision and opiate substitution therapy on the incidence of hepatitis C virus in injecting drug users: Pooling of UK evidence. Addiction. 2011 Nov;106(11):1978-88. doi: 10.1111/j.1360-0443.2011.03515

Amundsen E. J. (2006) Measuring effectiveness of the needle and syringe exchange programmes for prevention of HIV among injecting drug. Addiction 2006:101:911-12

Turner K M The impact of needle and syringe provision and opiate substitution therapy on the incidence of hepatitis C virus in injecting drug users: Pooling of UK evidence. Addiction. 2011 Nov;106(11):1978-88. doi: 10.1111/j.1360-0443.2011.03515

Wood E., Kerr T. (2006) Needle Exchange and the HIV Outbreak Among Injection Drug Users in Vancouver, Canada. . Subst Use Misuse 41 ( 6-7): 841-843 (doi:10.1080/10826080600669595) Strathdee S, Patrick D, Currie S, Cornelisse P, Rekart M, Montaner J, Schechter M, O'Shaughnessy M.(1997) Needle exchange is not enough: lessons from the Vancouver injecting drug use study. AIDS 11(8):F59–F65

Judd A, Hickman M, Jones S, McDonald T, Parry JV, Stimson GV, Hall AJ: Incidence of hepatitis C virus and HIV among new injecting drug users in London: prospective cohort study. BMJ 330(7481):24-5, 2005