Re-infection with hepatitis C has fallen among people with HIV in Europe

Keith Alcorn
Published:
20 January 2022

The rate of re-infection with hepatitis C has fallen sharply among people with HIV in Europe since the introduction of direct-acting antivirals, the EuroSIDA cohort study reports in the journal HIV Medicine.

People who are cured of hepatitis C by interferon-based treatment or direct-acting antivirals do not acquire immunity against subsequent infections. Sharing of injecting equipment or condomless anal sex can lead to re-infection and studies have reported high rates of re-infection in some settings. Most of these findings have come from cohorts of gay and bisexual men with HIV in western Europe and North America. Reported re-infection rates in people who inject drugs have been much lower. There is little evidence on re-infection rates in eastern Europe.

To investigate hepatitis C re-infection rates in people with HIV, and whether these have changed over time, the EuroSIDA cohort investigators looked for all people who had been cured of hepatitis C in the cohort and who had at least once hepatitis C RNA test result in the two years after they achieved a sustained virologic response.

EuroSIDA includes approximately 23,000 people with HIV in 35 countries in the European region, Israel and Argentina. Among these, 6915 had ever tested positive for hepatitis C RNA and 1022 had been cured of hepatitis C, had at least two years of follow-up and had been tested for hepatitis C RNA during follow-up.

The study population was predominantly male (78%) and White (86%) with a median age of 50 years. Just over half (52%) had acquired hepatitis C through injecting drug use.

Nineteen per cent were cured of hepatitis C before 2014, 91% by an interferon-based regimen. Twenty-one per cent were cured with an interferon-based regimen in 2014 or after and the remainder (60%) were cured with a direct-acting antiviral regimen in 2014 or after.

During the two-year follow-up period, 75 people were re-infected with hepatitis C. Thirty-one of these re-infections occurred before 2014, 18 in people cured by interferon-based therapy in 2014 or after and 26 in people cured by direct-acting antivirals in 2014 or after. The re-infection rate was highest in the pre-2014 group (18%) and lowest in the direct-acting antiviral group (4%).

Whereas more than half of those treated before 2014 had injecting drug use as their HIV transmission risk (58%), the proportion with injecting drug use as a transmission risk factor fell significantly from 2014 (p = 0.03).

The median time to a positive HCV RNA test after being cured was 8 months and did not vary over time.

The risk of re-infection was nearly 80% lower in people treated with direct-acting antivirals in 2014 or after (adjusted odds ratio 0.21, 95% confidence interval 0.11-0.38) and around 55% lower in those who received interferon-based treatment in 2014 or after (adjusted odds ratio 0.43, 95% confidence interval 0.22-0.83), when compared to people treated before 2014.

The study investigators say that a possible explanation for the reduced risk of re-infection after 2014 is the effect of wider treatment availability and uptake on the prevalence of hepatitis C. A reduction in the number of people with hepatitis C would lead to a reduction in the chance of acquiring hepatitis C.

The study cannot demonstrate whether the risk of re-infection is higher in one group or another as up-to-date information on injecting drug use is not available.

Reference

Amele S et al. HCV reinfection after HCV therapy among HIV/HCV-coinfected individuals in Europe. HIV Medicine, published online, 9 December 2021.

DOI: https://doi.org/10.1111/hiv.13212