Oncogenic infections: targets highly amenable to cancer prevention.

In the 60 years since Epstein-Barr virus (EBV) was identified as the first human oncogenic virus, the International Agency for Research on Cancer (IARC) has classified 13 infectious agents as carcinogenic. Globally, approximately 2.3 million cancer cases (12% of all cancers) are attributable to infection each year. Main causes are Helicobacter pylori (850 000), human papillomavirus (HPV; 730 000), hepatitis B virus (HBV; 380 000), EBV (240 000), and hepatitis C virus (160 000). Infection-attributable cancer burden varies greatly, exceeding 25% of all cancers in parts of Asia and in sub-Saharan Africa where HIV also causes an important cancer burden. Substantial progress in effective interventions has been made, often informed by IARC-led research. IARC Codes Against Cancer provide recommendations for reducing infection-attributable cancer risk including by prophylactic vaccines (HPV and HBV), diagnosis and treatment of infections (hepatitis C virus, HBV, HIV, and H. pylori), and screening to detect and treat precancerous lesions (HPV). Improving efficiency and implementation of existing interventions and developing novel tools (eg, EBV and H. pylori vaccines) are crucial.