A new large-scale study published by scientists from the World Health Organization (WHO) International Agency for Research on Cancer (IARC) found that in 2024, 2.3 million new cancer cases worldwide were directly attributable to infectious agents. This accounts for 12% of all new cancer cases globally.
The study highlights that the vast majority of these cases could be prevented using existing preventive measures.
The main “culprits”: infections
According to the study, five infectious agents are the leading causes of infection-related cancer:
- Helicobacter pylori (H. pylori) — 760,000 cases (4% of the global cancer burden). It is primarily responsible for stomach cancer.
- Human papillomavirus (HPV) — 750,000 cases (4%), mainly associated with cervical and other anogenital cancers.
- Hepatitis B virus (HBV) — 360,000 cases (2%), one of the major causes of liver cancer.
- Epstein-Barr virus (EBV) — 260,000 cases (1%), which can cause nasopharyngeal cancer and various types of lymphoma.
- Hepatitis C virus (HCV) — 160,000 cases (<1%), another major cause of liver cancer.
Notably, the updated global report includes cancers caused by HIV infection and Merkel cell polyomavirus (MCV) for the first time.
Geographical disparities
The geographical distribution of infection-related cancer cases is highly unequal. Low- and middle-income countries account for 77% of the burden.
The highest number of cases is recorded in Eastern Asia — 990,000 cases, or 42% of the global total — where H. pylori and hepatitis B are the main causes of infection-related cancers. The situation is also particularly serious in sub-Saharan Africa, where 25% of cancer cases are attributable to infections, primarily HPV. High rates are also recorded in Central and Eastern Europe.
Prevention
Scientists explain that the growing burden of these cancers could be substantially reduced using existing, evidence-based medical tools. However, in many cases, social, financial and political barriers prevent these measures from being adequately implemented.
Key strategies include:
- vaccination against HPV and hepatitis B;
- timely testing and treatment for HIV infection, H. pylori, and hepatitis B and C;
- screening for cervical cancer precursors;
- safe medical procedures, including injections, and prevention of HIV transmission.
At the same time, the researchers call on the global medical community to increase investment in new preventive tools, particularly the development of a vaccine against Epstein-Barr virus (EBV).
“Our findings highlight the vital importance of infection control for cancer prevention. It is essential to combine strategies at the global and local levels to ensure that preventive tools are accessible to everyone,” the study authors note.
