Infections linked to 12% of global cancer cases in 2024, study finds
A study by the International Agency for Research on Cancer estimates that 2.3 million new cancer cases in 2024 were caused by infections, highlighting preventable opportunities through vaccination and treatment.
The International Agency for Research on Cancer (IARC) reported that infections were responsible for about 2.3 million new cancer cases worldwide in 2024, representing roughly 12 percent of all diagnoses. The analysis, published in Lancet Oncology, identified five pathogens—Helicobacter pylori, human papillomavirus (HPV), hepatitis B virus (HBV), Epstein–Barr virus (EBV) and hepatitis C virus (HCV)—as the main contributors.
Helicobacter pylori accounted for an estimated 760,000 gastric cancers, while HPV was linked to about 750,000 cases, primarily cervical but also anal, vulvar, vaginal, penile and some head-and-neck cancers. HBV and HCV together were associated with roughly 520,000 liver cancer cases, and EBV contributed around 260,000 cases, mainly nasopharyngeal cancer and Hodgkin lymphoma.
Geographically, the highest infection-related cancer burdens were observed in Eastern Asia, Sub-Saharan Africa, Central and Eastern Europe, and South-East Asia, reflecting regional differences in infection prevalence, access to prevention and treatment, and broader socioeconomic conditions.
"The large geographic disparities show that this is an important global health equity issue," said Dr. Shan-Lu Liu, co-director of the Viruses and Emerging Pathogens Program at The Ohio State University.
IARC scientists emphasized that many of these cancers are preventable through existing interventions such as HPV and HBV vaccination, screening, and treatment of H. pylori, HBV, HCV and HIV. However, they noted that access to these measures remains limited in low- and middle-income countries due to financial, social and political barriers.
"Cancers caused by infectious agents are highly actionable targets because they can be prevented by vaccination, testing and treatment," said Dr. Gary Clifford, lead author of the study.
The researchers called on policymakers to scale up proven strategies, including expanding vaccination programs, improving infection screening and treatment, promoting safe injection practices, and strengthening cancer screening in high-risk populations.