BACKGROUND & AIMS:

On-going risk behaviour can lead to hepatitis C virus (HCV) reinfection following successful treatment. We aimed to assess the incidence of persistent HCV reinfection in a population of people who inject drugs (PWID) who had achieved sustained virological response (SVR) seven years earlier.

METHODS:

In 2004-2006 we conducted a multicentre treatment trial comprising HCV genotype 2 or 3 patients in Sweden, Norway and Denmark (NORTH-C). Six months of abstinence from injecting drug use (IDU) was required before treatment. All Norwegian patients who had obtained SVR (n=161) were eligible for participation in this long-term follow-up study assessing virological and behavioural characteristics.

RESULTS:

Follow-up data were available in 138 of 161 (86%) individuals. Persistent reinfection was identified in 10 of 94 (11%) individuals with a history of IDU prior to treatment (incidence rate 1.7/100 person-years (PY); 95% CI 0.8-3.1) and in 10 of 37 (27%) individuals who had relapsed to IDU after treatment (incidence rate 4.9/100 PY; 95% CI 2.3-8.9). Although relapse to IDU perfectly predicted reinfection, no baseline factor was associated with reinfection. Relapse to IDU was associated with age <30years (vs. ⩾40years) at treatment (adjusted odds ratio [aOR] 7.03; 95% CI 1.78-27.8) and low education level (aOR 3.64; 95% CI 1.44-9.18).

CONCLUSIONS:

Over time, persistent HCV reinfection was common among individuals who had relapsed to IDU after treatment. Reinfection should be systematically addressed and prevented when providing HCV care for PWID.

Cette réinfection survient dans 11 % des cas, chez les usagers de drogues, le taux de réinfection survient d’autant plus que le patient est jeune lors du primo traitement et qu’il présente un niveau socio économique bas.