High hepatitis C virus reinfection in a community-based sample of people who inject drugs in Imphal, India

Background: Reinfection with hepatitis C virus (HCV) following successful treatment with direct-acting antivirals (DAAs) is a threat to achieving the World Health Organization viral hepatitis elimination goals. Given the limited data among people who inject drugs (PWID) from low-and-middle-income countries (LMICs), we characterized HCV reinfection among PWID in Imphal, India.

Methods: Our study population included PWID who achieved a sustained virologic response (SVR) after DAA treatment at community-based treatment programs located in harm reduction centers. Reinfection rates per 100 person-years (PY) were calculated overall and by select characteristics. Poisson regression was used to estimate incidence rate ratios and correlates of reinfection.

Results: Among 1267 PWID who achieved SVR and were screened for this study, 315 instances of reinfection were documented over 2395 PY of follow-up with an incidence rate (IR) of 13.2 per 100 PY (95 % CI: 11.8, 14.7). The incidence of reinfection was highest among those 18-24 years old (20.0 per 100 PY, 95 % CI: 16.9, 23.8) and in multivariable analysis, age remained independently associated with reinfection risk. Those 18-24 years old had the highest incidence (adjusted incidence rate ratio (aIRR) compared to 45-54 years: 4.94 [95 % CI: 2.59, 9.42]). The use of medication for opioid use disorder (MOUD) was also associated with reinfection in those reporting recent injection (aIRR: 1.57 [95 % CI: 1.19, 2.09]).

Conclusions: The high reinfection rate among PWID in Imphal, a setting with comprehensive harm reduction programs, highlights the need to integrate and innovate models of HCV care and harm reduction service delivery with a particular emphasis on young PWID.