A new study shows the benefits of using a quick clinic-based diagnostic test for hepatitis C virus (HCV) infection over a standard laboratory-based test.
Lancet Gastroenterology and Hepatology published the new study led by the World Health Organization (WHO) in collaboration with the University of Bristol.
The Hepatitis C Virus
Chronic hepatitis C virus (HCV) infection is a major global public health problem and a cause of liver disease, with the highest burden in low-and middle-income countries (LMICs). In 2016, WHO launched the Global Health Sector Strategy for Viral Hepatitis which was renewed in 2022, with a goal of ending the epidemics of viral hepatitis B and C by 2030.
The organization had made progress with more than 10 million persons with chronic HCV infection having been cured using a 12-week short course direct acting antiviral treatment. However, as of 2019 there were still 58 million people with chronic HCV, resulting in 399 000 deaths. Only 20% of those infected worldwide had been diagnosed and 13% treated.
To close this gap and achieve WHO targets for eliminating HCV, patient care pathways must be simplified, including diagnostic approaches. The standard approach to diagnosis of chronic HCV infection is initial screening with an HCV antibody test, followed by a laboratory-based molecular HCV viral load (VL) testing, to confirm the presence of active virus and need for treatment.
However, access to laboratory-based viral load tests remains limited in many LMICs. As a result, many of those with chronic HCV are never linked to care and treatment.
Using Point-of-Care Testing
HCV VL assays performed on point-of-care (POC) devices outside of the laboratory and in a clinic near to where patients receive care are being increasingly used as an alternative approach to laboratory-based diagnosis.
WHO already recommends the use of these POC assays for diagnosis and monitoring of other infectious diseases, including tuberculosis, COVID, and HIV. Until recently, there had been limited data on their use in improving access to and uptake of HCV testing and treatment.
This new study pooled results from 45 studies (around 50% were from LMICs) and compared POC HCV viral load assays with centralized, laboratory-based standard approaches. It showed that using POC HCV viral load assays led to faster times from initial HCV antibody screening to starting on treatment (19 days compared to 67 days). Overall uptake of treatment was higher with POC assays at the clinic site (77%) or delivered in mobile units (81%) compared with standard laboratory-based assays (53%). The best results were seen when the POC assays were placed at a site where both testing and treatment were offered at the same location enabling treatment to be started on the same day as diagnosis.
The findings from this study led to recent WHO recommendations for adoption of POC HCV viral load testing as an alternative approach to laboratory-based platforms for diagnosing HCV infection and speeding up starting curative treatment. This recommendation complements other recent WHO recommendations in the same updated guidance for HCV diagnosis and treatment that promotes simplification of service delivery and task-sharing of testing and treatment to nurses and non-specialist doctors.
The optimal populations and settings for POC assays are hard to reach or marginalized populations at high risk of loss to follow-up, such as persons who inject drugs or persons experiencing homelessness. The POC assay can be placed in harm-reduction clinics, primary care clinics, prisons, in mobile units or even in community clinics, and offers the possibility of a one-stop, same-day diagnosis and treatment of HCV infection.
WHO is encouraging affected countries to consider including use of POC assays in their national policies on hepatitis C. The COVID pandemic prompted a major expansion of these POC diagnostic assays in many LMICs, which provides an opportunity to share their use for HCV VL testing and therefore reduce costs. Many countries including Australia, Cambodia, Malaysia and Myanmar have adopted use of these POC assays in their national programmes.
WHO is now also undertaking a similar evaluation of POC viral load assays for hepatitis B in its planned 2023 updated guidance.