One Vancouver clinic finds low rates of HCV reinfection after cure

People who share equipment for substance use are at increased risk for infection with germs, including hepatitis C virus (HCV) and HIV. In the past five years, powerful treatments called DAAs (direct acting antivirals) for HCV infection have become available and, as a result, more people are being cured. However, if the drivers of substance use are not addressed—addiction, mental health issues and so on—then it is possible that in some cases reinfection could occur.

To investigate the issue of reinfection, researchers at the Vancouver Infectious Disease Clinic reviewed the medical records of several hundred people who had been treated and cured of HCV. They found that cases of reinfection were very low. This low rate of reinfection is likely underpinned by the clinic’s multidisciplinary approach toward HCV infection and substance use.

Study details

Researchers focused on 340 participants, all of whom had previously injected street drugs (most commonly cocaine and heroin). The average profile of participants while being treated was as follows:

• age – 53 years
• 75% were men and 25% were women
• co-infection with HIV and HCV – 52%
• about 36% of participants were taking opioid substitution while they were treated for HCV

Participants who were cured returned to the clinic every six months to receive clinical and laboratory monitoring, including tests for HCV’s genetic material. This latter test reveals if active HCV infection is present. If routine laboratory monitoring detected elevated liver enzyme levels in the blood or if the patient had symptoms suggestive of HCV infection, then clinic staff would request more frequent screening for HCV’s genetic material.

Results

Out of 340 participants, 306 (90%) were cured of HCV. Of those who were cured, about 38% continued to inject street drugs.

After an average monitoring period of two and a half years, researchers found that four out of 306 participants (about 1%) became reinfected with HCV.

Focus on the four cases

Here is a brief profile of the four cases:

• all were men
• they were aged between 47 and 60 years
• all used amphetamines and three of the four also used heroin
• two of the men attended support group meetings
• three of the men had been diagnosed with mental health conditions, including depression, bipolar illness and schizophrenia

The Vancouver researchers noted that the rate of HCV reinfection was very low. They also stated that the risk of reinfection among people who use substances and who receive psychological support is likely to be low. Intensified multidisciplinary approaches for the care and support of people who are recovering from HCV infection and addiction will likely continue to help minimize reinfection rates.

—Sean R. Hosein

REFERENCE:

Hakobyan S. HCV re-infection in high-risk people who inject drugs. The International Liver Congress, 13-17 April 2017, Barcelona, Spain. Abstract SAT-272.