The challenges of research into preventing and responding to blood borne viruses
The National Drug Research Institute's (NDRI) involvement in injecting drug use and blood borne virus research spans more than two decades and can be broadly defined as epidemiology and behavioural research. HIV transmission risk via injecting drug use (IDU) and sexual behaviours were the foci of early research, but by the early 1990s a second virus affecting those who inject drugs had been identified. While concern about HIV/AIDS continued, the focus broadened to include the new virus, hepatitis C (HCV).
The first research foray of NDRI, or the National Centre for Research into the Prevention of Drug Abuse (NCRPDA) as we were initially known, into licit and illicit drugs was conducted in 1986, and involved the collection of alcohol and illicit drug use data among metropolitan and rural Western Australian (WA) participants. The study was conducted in order ‘to address the need for large probability sample surveys related to adult self-reported drug consumption’ (pp iii, Blaze-Temple et al, 1987). Almost 1000 Western Australians responded to questions about their consumption of alcohol and a range of licit drugs (tobacco, aspirin, tranquilisers and sedatives) and illicit drugs (including cannabis, heroin, cocaine, petrol and glue, speed and hallucinogens). Cannabis was the most frequently tried illicit drug (17.2%) followed by hallucinogens (2.5%) and speed (2.1%). More than 25% reported regular use of tobacco and 5% regular use of aspirin. Although injecting drug use had been identified as a high risk behaviour for the transmission of HIV/AIDS by the time this survey was conducted, questions relating to the method of illicit drug administration were not included.
At around the same time this study was being conducted in 1986, the first needle and syringe provision program was being pilot tested in Sydney (ANEX, 2014), and the testing of used syringes collected at the site confirmed that HIV was present among IDU using this facility. It is no surprise therefore that closely following the community consumption survey described above came the ANAIDUS (Australian National AIDS and Injecting Drug Use Study, 1991). This was a cross sectional survey of injecting drug users, conducted in 1989, and designed to describe the variables associated with the risk of HIV among IDU in Australia. It was the first national study to attempt to collect sero-prevalence data on HIV/AIDS among injecting drug users and had as its prime focus ‘to provide baseline data, inform policy, and provide information of use to those who are planning and implementing interventions to prevent the spread of HIV’ (page 103, ANAIDUS, 1991).
ANAIDUS, which included WA data collection, was NDRI’s first undertaking in BBV-driven research. This national cross sectional study of 2500 people who injected drugs found a low overall national prevalence of HIV among those whose only risk factor was injecting. Self-reported HIV positive status ranged from 3.4% in Perth to 6.8% in Sydney (overall less than 5%). For those not previously tested, dried blood spot testing was carried out and a further 36 individuals were identified as HIV positive. HIV prevalence varied greatly by sexual orientation, leading the authors to suggest that ‘a significant proportion of the sero-prevalence was sexually transmitted’. The authors concluded that, compared to other Western cities, HIV among IDUs in Australian was low. The study also identified that many IDU had already changed their injecting behaviours in response to the threat of HIV/AIDS, assisted by government policy supporting the provision of clean injecting equipment to control the transmission of HIV/AIDS among Australia’s IDU population. They reported ‘significant use of new injecting equipment, common cleaning of equipment when it was re-used, and sharing of used equipment ‘generally confined’ to one or two close friends or lovers.’
By the time ANAIDUS data had been published in 1991, antibodies to a new virus, hepatitis C (previously known as non A-non-B hepatitis), had been identified and found to be most efficiently transmitted via parenteral means. Following the development of a blood test for HCV antibodies it quickly became clear that this latest virus had been spreading among those who injected drugs in Australia since the 1960s. The testing of stored blood from patients admitted to an infectious diseases clinic in Victoria between 1971 and 1975 identified 17% had markers for HCV infection, and 90% of those with markers of HCV had a history of injecting drug use (Thompson et al, 1995). High rates of exposure among methadone clients were also found and, unlike for HIV/AIDS, methadone treatment was not found to decrease continuing exposure to the virus (Crofts et al, 1997). Studies in prisons in Victoria found alarming rates of HCV among those with a history of IDU, in particular among males under the age of thirty (Crofts et al, 1995).
The Australian Study of HIV and Injecting Drug Use (ASHIDU) conducted in 1993 across 4 states in Australia was the first study, managed by NDRI, to provide national figures on HCV prevalence among 872 people who inject drugs (PWID). It demonstrated an alarming rate of HCV antibodies among PWID along with a close correlation between duration of injecting drug use and prevalence of HCV antibodies, and a continuing modest prevalence of HIV independent of homosexual status (Loxley et al, 1995). A concern that young people were at high risk of exposure to HCV led to a WA based study of more than 200 young injectors (under the age of 21 years) (Carruthers & Loxley, 1995). Among this group, who had been injecting for less than two years, prevalence was 6% and low levels of concern about HCV in combination with a lack of knowledge and continued needle sharing suggested that on-going transmission among this group of younger injectors was likely to continue.
1995 was also the year that the Annual Needle and Syringe Program survey commenced, managed by the National Centre for HIV Epidemiology and Clinical Research (NCHECR; now the Kirby Institute). This annual cross sectional survey continues to this day, and has provided 20 years of data on the prevalence of BBV among people who regularly inject. A re-analysis of data from this survey between 1995 and 2004 concluded that ‘a persistent HCV epidemic exists despite significant harm reduction efforts in Australia since the mid-1990s, with HIV incidence effectively constant in successive initiation cohorts’ (Falster et al, 2005).
With annual surveillance of blood borne viruses now undertaken by NCHECR, NDRI’s focus on IDU research shifted in an attempt to understand the psych-social context of injecting drug use among young Western Australian injectors (under 21 years). This qualitative research identified that youth in WA felt they were at little risk of exposure to HIV/AIDS, had limited knowledge of HIV and prevention of transmission, and a ‘range of constraints prevented them from enacting their wish to remain HIV/AIDS free’ (page i, Loxley & Hawks, 1997). This qualitative study was followed by another which specifically examined HCV among established and new initiates to injecting (Carruthers, 2002). This innovative study utilised video-recording of injecting events in an attempt to understand why IDU were continuing to be exposed to HCV despite maintaining they had ‘never’ shared needles and syringes. The deconstruction of the recorded injecting event identified that while clean needles and syringes were being used, the sharing of a range of other injecting equipment (swabs, water, spoons) could be responsible for on-going transmission. It was not enough to ensure that clean needles and syringes were used; clean equipment and scrupulous attention to detail was likely to be needed if injectors were to remain free of the virus. It seemed that the highly social nature of injecting drug use, particularly with the use of heroin, conspired against individuals remaining HCV free.
It was about this time that attention turned to the treatment of HCV as a means of controlling the continuing epidemic of HCV among injectors. However, uptake of treatment among current injectors in the first decade of the 21st century was, and remains, low at less than 1% (Alavi et al, 2014). Attention turned to HCV treatment in prison, with prison deemed to be an ideal setting in which prolonged and difficult treatment could be successfully completed. To date, two studies at NDRI looking at the barriers and enablers into treatment in prison are on-going, but early findings suggest there are numerous barriers to treatment in prison to be overcome, and continued injecting drug use in prisons represents continuing risk of exposure to the virus. Nevertheless, hepatitis C treatment is delivered at many corrective services sites and new, more effective treatments with fewer side effects should increase the ability of prisons to treatment more people with HCV.
Major advances in HCV treatment have occurred over the past ten years, and new agents free of the debilitating side effects of interferon are now available. Treatment as prevention may be possible in the coming decade although, as pointed out by Grebely et al (2013), efforts to address HCV through new treatment will rely on the development of an appropriate infrastructure, reducing the cost of new medications and addressing the balance of competing health priorities among those who inject.
Where to from here?
In the continued absence of an effective preventative vaccine for HCV, controlling the on-going epidemic of HCV remains difficult. Promising new treatments may contain the answer to reducing the prevalence of the virus, which in turn should reduce on-going transmission. However, issues to do with reinfection following successful treatment remain a concern and are not yet fully understood. In the meantime, it is critical that we employ a broad range of responses: effective drug prevention strategies; enhanced access to effective drug treatment; and increasing access to strategies that reduce BBV transmission, including clean injecting equipment and peer and outreach contact with current injectors.
Alavi, M., Raffa, J., Deans., G., Lai, C., Krajden, M., Dore, G., Tyndall, M. & Grebely, J. (2014) Continued low uptake of treatment for hepatitis C virus infection in a large community based cohort of inner city residents. Liver International, 34, (8), 1198 – 1206.
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Carruthers, S. & Loxley, W. (1995) Hepatitis C and young injecting drug users: are they about to join the epidemic. Australian Journal of Public Health, 19, (4), 421-424.
Carruthers, S. (2002) Hepatitis C and novice injecting drug users: assessing the risks and designing the messages. National Drug Research Institute, Curtin University of Technology, Perth, Western Australia.
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Falster, K., Kaldor, J. & Maher, L. (2005) Hepatitis C acquisition among injecting drug users: A cohort analysis of a national repeated cross-sectional survey of needle and syringe program attendees in Australia, 1995 – 2004. Journal of Urban Health, 86, (1). Doi:10.1007/s11524-008-9330-7.
Grebely, J., Matthews, G., Lloyd, A. & Dore, G. (2013) Elimination of hepatitis C virus infection among people who inject drugs through treatment as prevention: Feasibility and future requirements. Clinical Infectious Diseases, 57, (7), 1014-20.
Loxley, W. & Hawks, D. (1994) AIDS and injecting drug use: very risky behaviours in a Perth sample of injecting drug users. Drug and Alcohol Review, 18, (1) , 21-30.
Loxley, W., Carruthers, S & Bevan J. (1995) In the same vein: First report of the Australian Study of HIV and Injecting Drug Use (ASHIDU). NCRPDA, Curtin University of Technology, Perth, Western Australia.
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