Like HIV, hepatitis C virus occurs at high prevalence in certain population groups:
- migrants in precarious circumstances (2% to 5%)
- prisoners: prevalence five times that in the general population
- drug users: critical situation, with prevalence above 40%.
Research on prevention should therefore evaluate risk reduction strategies. Moreover, the efficacy of direct-acting antivirals in treatment of hepatitis C virus infection has significantly transformed the challenges facing social sciences research, by accentuating the need to improve access to screening and to treatment of those most affected by this virus.
In 2014, in France, close to 43% of people with chronic hepatitis C were unaware of their virological status. This hidden epidemic reduces the therapeutic chances of individuals infected by this virus, but also increases the risk of transmission in the population. It is therefore essential to improve the screening offer so as to reach the people most at risk of infection, notably those who do not attend the usual treatment facilities.
Rapid all-in-one screening
Research findings show that rapid screening for HIV outside a medical setting is both acceptable and feasible. These rapid screening tests are performed by accredited members of nonprofit organizations. The study ANRS Cube is evaluating the relevance of extending this type of combined screening for HIV/HBV/HCV, plus vaccination against hepatitis B virus, to the people most at risk of infection by one of these three viruses.
Hepatitis C is an asymptomatic infection that may remain unrecognized for many years. A small proportion of these infected individuals will spontaneously eliminate the virus, but in 70% to 90% the infection will progress to chronic hepatitis C. In HIV-infected people, this spontaneous elimination is even less effective. In people co-infected with HIV and HCV, the first results of the use of new treatments against HCV, without interferon, during the acute phase, show good safety and high efficacy. Early screening and treatment would seem to be beneficial collectively in reducing the risk of HCV transmission.
Cost-efficacy of early treatment in HIV-positive men who have sex with men
One study supported by the ANRS is assessing the impact in France of screening and early treatment of hepatitis C infection in HIV-infected men who have sex with men, a population in which sexual transmission of HCV is not negligible.
In France, the HCV epidemic essentially affects intravenous drug users, in whom the latest figures show a prevalence of 64%. Prisoners are also particularly affected, prison being a setting at particularly high risk of exposure to infection (by HIV and hepatitis B and C), because of the characteristics of the prison population and prison organization.
Efficacy of replacement therapy for cocaine users
The study ANRS STIMAGO is evaluating the benefits and risks of a psychostimulant in people dependent on cocaine or crack, and the impact of such treatment on practices involving the risk of HCV transmission.
Efficacy of opioid replacement therapy for opioid users
In France, despite the access to opioid replacement therapy (buprenorphine and methadone taken orally), certain drug users continue to inject drugs. ANRS BUPIV will therefore evaluate an injectable treatment based on buprenorphine for opioid-dependent subjects, mainly to evaluate the efficacy of such treatment, but also to assess its effect on practices involving a risk of hepatitis C infection, complications associated with the injection, etc.
Prevention in a prison environment
Prison is an environment that cumulates a high infectious risk (large proportion of drug users, high prevalence of HIV and of HCV) and insufficient access to risk reduction measures (condoms, syringe exchange program, liquid bleach, screening for HIV and hepatitis).
The study ANRS PRIDE will analyze the obstacles to the setting up of a suitable risk reduction policy in prisons, by assessing the acceptability of such a policy to all categories of personnel and to prisoners. The study will be rolled out in 2017 in the Baumettes penitentiary in Marseille and deployed from 2018 in three other prisons in France and a French overseas department.
Data on hepatitis B and hepatitis C infections are scarce in French Guiana. The region along the Maroni River, on the border with Suriname, is particularly affected. It comprises highly mobile Amerindian and Maroon communities that are isolated, vulnerable, and at high risk of infection because HIV screening is rare among these people, for whom we lack epidemiological data.
The risk of hepatitis B and C infection is high because of poor vaccine coverage against HBV, a low rate of screening, and delayed access to care and treatment. It is therefore essential to explore the viral hepatitis epidemic in the population along the Maroni River, because the scarcity of data hampers planning of healthcare interventions.
The ANRS supports a study designed to estimate hepatitis B prevalence and infection status and the prevalence of hepatitis C, hepatitis D, and HIV in the general adult population in the Maroni River region. This study will also analyze the distribution of genotypes and risk factors for infection by these viruses. The study started in 2016 and will involve 2500 adults.