12 April 2022
The World Health Organization (WHO) has set a target of eliminating hepatitis C virus (HCV) globally by 2030. Researchers from the University of Bristol have questioned how countries will know whether the target has been met and devised different ways of measuring elimination taking into account different country contexts. The results have been published in The Lancet Gastroenterology and Hepatology and have informed recent WHO guidance.
Hepatitis C infects over 70 million people worldwide (about 1% of the world’s population) and causes 400,000 deaths each year. Elimination of HCV is defined as an 80% reduction in new cases of infection (incidence) and 65% reduction in HCV-related deaths from a baseline of new cases and deaths in 2015.
The gold-standard method for assessing whether a country has achieved the target involves following up and re-testing people identified as at risk of HCV infection, including people who inject drugs and men who have sex with men. This method is resource-intensive so may not be possible for some countries. Some countries may also not have good quality data from 2015 against which to measure their progress.
Using mathematical modelling, the researchers explored the usefulness of four indicators that might be more easily measured in countries where HCV incidence is difficult to monitor. They also considered the advantages and disadvantages of using an absolute HCV incidence target – that is, a universal threshold to be met by all countries in 2030 – and proposed what that threshold might be.
Of the four indicators, two – trends in chronic HCV prevalence and trends in the scale-up of HCV prevention and treatment interventions – were found to be good proxies for HCV incidence and could be used as reliable alternatives for validating elimination.
The researchers also concluded that both relative and absolute elimination targets would be needed: the former so that countries with high rates of new HCV infections in 2015 could demonstrate their achievement relative to the baseline, and the latter so that countries with poor quality data in 2015 could measure their achievement in absolute terms.
Dr Adelina Artenie, Senior Research Associate in Mathematical Epidemiology at Bristol Medical School and lead author of the study, said: “As the 2030 deadline for eliminating HCV infection approaches, there is a need for countries to prepare for how they are going to validate elimination or demonstrate progress towards the target. We have proposed a number of options that give countries some of the flexibility needed to do that in ways that are best suited to their context.
“Our recommendations have informed the interim framework recently developed by World Health Organization, which provides guidance on country validation of elimination of chronic HCV and hepatitis B virus infection as public health problems.”
Paper: Methods and indicators to validate country reductions in incidence of hepatitis C virus infection to elimination levels set by the World Health Organization by Adelina Artenie et al. Published in The Lancet Gastroenterology and Hepatology.
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