WHO Classifies Hepatitis D Virus as Carcinogenic to Humans

In August 2025, the World Health Organization (WHO) and the International Agency for Research on Cancer (IARC) reclassified the Hepatitis D virus (HDV) as a Group 1 carcinogen, confirming it as a known cause of liver cancer alongside Hepatitis B and C.

Key Points

Global Burden: Hepatitis B, C, and D affect over 300 million people worldwide, causing around 1.3 million deaths annually, primarily due to liver cirrhosis and cancer.
HDV infects about 5 per cent of people with chronic HBV, equating to nearly 12 million individuals globally.
High-Risk Groups: Populations in regions with high HBV prevalence — including parts of Asia, Africa, and the Amazon Basin — as well as people who inject drugs and haemodialysis patients are at greater risk.
Why HDV is Dangerous: HDV can only infect individuals already carrying HBV, using it to replicate.
Transmission: The virus spreads via infected blood, unprotected sex, unsafe injections, and occasionally from mother to child during birth.
Symptoms may include fatigue, nausea, abdominal discomfort, dark urine, or jaundice, but are often overlooked.
Treatment Options: HBV can be managed with lifelong antivirals, but HDV treatments are limited.