Five infections linked to more than 2 million new cancer cases in 2024

A team of cancer epidemiologists published updated global estimates in The Lancet Oncology showing infections were linked to about 12 percent of cancers diagnosed in 2024—approximately 2.3 million new cases. Five infectious agents were responsible for nearly all of those infection-associated cancers.

• Human papillomavirus (HPV): Also linked to about 4% of cancers — roughly 750,000 cases. HPV is a major preventable cause of several cancers.
• Hepatitis B virus (HBV): Accounted for about 2% of new cancers in 2024.
• Epstein–Barr virus (EBV): Linked to about 1% of cancers. Evidence tying EBV to cancer has strengthened since earlier global estimates.
• Hepatitis C virus (HCV): Responsible for less than 1% of cancers.

Most infection-related cancer cases occurred in low- and middle-income countries. Regions with the highest burden included eastern Asia, sub-Saharan Africa, and southeast Asia. Eastern Asia alone made up 42% of infection-linked diagnoses in 2024, driven primarily by H. pylori and HBV.

Prevention and treatment opportunities

The analysis highlights that many of these infection-linked cancers are avoidable through existing public-health measures. Concrete interventions named by the researchers include vaccines, diagnostics, treatments, and safer injection practices.

• HPV and HBV vaccines are proven measures that can reduce cancer incidence when delivered widely. The authors emphasize increasing vaccine coverage, including expanding HPV vaccination to males in settings where they are not routinely targeted.
• H. pylori is a major contributor but presents a harder target. There has been limited progress on an effective H. pylori vaccine. Current therapeutic approaches risk ineffective antibiotic exposure when applied broadly, and more effective strategies are needed to reduce gastric cancer globally.

The paper stresses that known, cost-effective prevention strategies are often underused because of financial, political, and social barriers—especially where the need is greatest. The authors call for more investment in prevention given the economic and social costs of cancer.

What this means for individuals and policymakers

For individuals: vaccination where recommended (HPV and HBV), following screening guidelines, and seeking medical care for chronic infections are practical ways to reduce risks.

For policymakers and health systems: expanding vaccine programs, improving access to diagnostics and safe clinical practices, and investing in development of vaccines and better therapies for pathogens such as H. pylori and EBV could substantially reduce future cancer burden, particularly in lower-resource settings.