World Hepatitis Day 2022: The Road to Elimination
July 28th marks World Hepatitis Day, and this year’s theme is ‘I can’t wait’, highlighting the need to act fast to tackle viral hepatitis.
Across the globe, more than 350 million people live with viral hepatitis, and somebody dies of a hepatitis-related illness every 30 seconds. Although viral hepatitis is a global phenomenon, it affects low- and middle-income countries the most severely.
Viral hepatitis occurs when a viral infection causes inflammation of the liver. There are five main strains of viral hepatitis, labelled A to E, which all behave differently. Hepatitis can range from mild to severe; some people experience no symptoms at all, whilst others suffer life-threatening infections. In some cases, particularly when patients experience chronic hepatitis B or C, hepatitis can lead to serious complications, like scarring of the liver (cirrhosis) and liver cancer.
In 2016, the World Health Organisation devised a roadmap to eliminate viral hepatitis as a public health threat by 2030. To achieve this, WHO has set targets for the reduction of new infections, the reduction of deaths from cirrhosis and liver cancer, improved access to diagnosis, and improved access to treatment.
Understanding and tackling viral hepatitis requires a broad range of skills and expertise, spanning disciplines from immunology to mathematics. In this post, we’ll highlight just some of the ways in which interdisciplinary research across Imperial is helping to make WHO’s elimination roadmap a reality.
Organ-on-chip technology: using bioengineering to simulate hepatitis B
Imperial scientists were among the first in the world to study how pathogens interact with artificial human organs.
An organ-on-a-chip is a microtechnology than contains live human cells. The chip can control the cells’ characteristics, allowing the system to mimic a human organ.
In a 2018 study, a team of scientists, including specialists in virology and hepatology from what was then Imperial’s Department of Medicine, studied the ways in which a liver-on-chip system responded to the hepatitis B virus. They were the first in the world to study the interaction between a pathogen and an artificial organ.
They found that the artificial liver responded to the hepatitis B virus very similarly to a real human liver. This means that the liver-on-a-chip is a useful tool for studying hepatitis B, understanding how the immune system responds to it, and even testing how drugs can be used to treat the virus.
Getting down to business: increasing access to hepatitis C medication
Changing the way that pharmaceutical companies license medicines can make expensive hepatitis drugs more accessible.
The medications used to treat hepatitis C are expensive. This means that many patients living in low- and middle-income countries simply cannot afford the treatment they need. But, a 2019 study, conducted in collaboration between the Imperial College Business School and what was then the Department of Medicine, found that changes to pharmaceutical licensing agreements can help bring the price of hepatitis C drugs down.
Normally, patented medicines can only be produced by the manufacturer that owns the patent. This means the manufacturer has the power to set the price. But, pharmaceutical companies can choose to issue ‘voluntary licenses’, which allow other companies to make these medications, too.
In this study, researchers found that when voluntary licenses allowed manufacturers in low- and middle-income companies to produce hepatitis C drugs, the competition in the market brought prices down. This meant that more people were able to access the medication they needed.
Catching cancer early: finding new ways to diagnose liver cancer
Finding new ways to diagnose liver cancer could lead to better outcomes for patients.
Chronic hepatitis B and C infections can lead to a type of liver cancer called hepatocellular carcinoma (HCC). Patients with HCC often don’t notice symptoms until the disease is in a late stage. This means it’s difficult to diagnose HCC early, and as such, prognosis for patients is often poor. Scientists, including researchers from what was then Imperial’s Department of Metabolism, Digestion and Reproduction, are looking for better ways to diagnose HCC.
Over the years, many studies have suggested potential ‘biomarkers’ which could be used to diagnose HCC. A biomarker is a biological characteristic that can indicate illness. For example, certain molecules in the blood can be used as biomarkers for heart health.
In this study, the team compiled a database of potential biomarkers suggested in previous research, and developed a new statistical tool to assess the potential of each one. This could help future studies focus their efforts in the right places.
Doing the maths: modelling the elimination of hepatitis C
Mathematical modelling predicts that over 15 million hepatitis C infections could be prevented by 2030.
In 2019, research led by Alastair Heffernan from Imperial’s School of Public Health found that over 15 million new hepatitis C infections could be prevented by 2030, if a range of prevention, screening and treatment measures were adopted. This would prevent 1.5 million deaths from cirrhosis and liver cancer.
Hepatitis C is transmitted through blood-to-blood contact, meaning it can spread in unsafe healthcare settings, and amongst people who inject drugs.
This study found that four interventions – improving blood safety measures, offering drug users more health and safety support, increasing treatment provision, and expanding access to testing – could drastically reduce the number of people contracting hepatitis C. If we adopt these measures, we could meet the WHO target of reducing new hepatitis C infections 80% by 2030. Deaths could be reduced 65% by 2032.