Transmission, reinfection common in prisoners with HCV who inject drugs
Hepatitis C transmission rates were high in Australian prisons and significantly correlated with injection drug use, according to a presentation at the International Symposium on Hepatitis Care in Substance Users. Additionally, prisoners were doubtful of the long-term efficacy of treatment-as-prevention in the prison setting.
“In the high-risk setting of the New South Wales prisons — where approximately one in four individuals have chronic hepatitis C infection and injecting drug use is prevalent — ongoing transmissions (both primary infection and reinfection) are common,” Andrew Lloyd, MD, FRACP, researcher with The Surveillance and Treatment of Prisoners with Hepatitis C study (SToP-C) and the Kirby Institute at the University of New South Wales, Sydney, told Healio.com/Hepatology.
“This is despite the widespread availability of the disinfectant (Fincol) to clean the injecting apparatus, and reasonable availability of opioid substitution therapy (OST),” Lloyd continued, “neither of which were found to be associated with protection against infection. This argues for new prevention strategies. One such potential strategy is direct-acting antiviral treatment as prevention.”
To evaluate the incidence of HCV in the prison setting and develop a framework for treatment-as-prevention programs, the researchers enrolled prisoners from two maximum-security prisons in New South Wales from October 2014 through 2017.
Of the 332 prisoners with at least one follow-up, 203 were previously imprisoned, 131 reported ever using injection drugs, 80 reported ever using injection drugs in the current imprisonment, 58 reported injecting in the last 6 months in prison, and 41 reported injecting in the past month in prison. Thirty-four of those who used injection drugs in the prior month reported sharing a needle and 30 reported injecting weekly or more frequent.
The final analysis included 171 prisoners, of whom 122 researchers considered at risk for primary infection and 49 were at risk for reinfection. In 178 person-years of follow-up, the researchers observed five primary infections and four reinfections (incidence rate, 5.1 per 100 person-years; 95% CI, 2.6-9.7). All nine prisoners with incident HCV reported injection drug use and five reported injection drug use within the past month in prison.
Among prisoners who reported ever using injection drugs, overall HCV incidence was 13 per 100 person-years (95% CI, 6.8-25), primary incidence was 18.6 per 100 person-years (95% CI, 7.7-44.7), and reinfection incidence was 9.4 per 100 person-years (95% CI, 3.5-25.1). Overall HCV incidence was significantly higher among those who reported injection drug use in the past month at 35.5 per 100 person-years (95% CI, 14.8-85.3), all of whom reported needle or syringe sharing.
The factors significantly associated with HCV incidence after an adjusted analysis included a history of injecting but not in current imprisonment (HR = 11.92; 95 CI, 1.33-106.97), injected more than 1 month ago in the current imprisonment (HR = 20.96; 95% CI, 2.53-173.25), and injected in the previous month in current imprisonment (HR = 19.17; 95% CI, 2.23-164.86).
Prisoners express doubt
Lise Lafferty, a research associate at the Centre for Social Research in Health at the University of New South Wales, also presented data from the SToP-C study at the symposium. According to a survey of 32 prisoners from four correctional facilities, most participants voiced concern about initial transmission and reinfection. However, the participants were doubtful regarding the long-term efficacy of treatment-as-prevention without effective prevention measures in place, due to factors such as prisoners moving between prisons or untreated new prisoners entering the system.
According to the prisoners surveyed, suggestions for harm reduction measures to assist treatment-as-prevention included education about HCV and risks factors, increasing access to opioid substitution therapy and prison needle/syringe programs.
“It is absolutely clear that universal access (ie, unrestricted and subsidized access) to testing [antibody and polymerase chain reaction] and to DAA treatment is a cornerstone of plausible HCV elimination,” Lloyd said. “How successful this cornerstone will be in elimination will soon become evident in Australia, noting that two other cornerstones are key: firstly, models of care which successfully engage the affected populations, including [people who inject drugs] in assessment and treatment; and secondly, additional prevention strategies which ensure low rates of reinfection.” – by Talitha Bennett
Hajarizadeh B. Incidence of Hepatitis C Virus Infection in Two Maximum-Security Prisons in New South Wales, Australia: The SToP-C Study. Presented at: International Symposium on Hepatitis Care in Substance Users; Sept. 6-8, 2017; New York.
Lafferty L. Treatment as Prevention in the Prison Setting: Prisoners’ Perspectives. Presented at: International Symposium on Hepatitis Care in Substance Users; Sept. 6-8, 2017; New York.
Disclosure: The researchers report no relevant financial disclosures.