One in Eight Cancers Worldwide Linked to Infections, WHO Agency Finds

An estimated one in eight cancer cases diagnosed worldwide are linked to infections, according to a new study from the International Agency for Research on Cancer (IARC), the World Health Organization's specialized cancer research agency.

The study found that approximately 2.3 million new cancer cases worldwide in 2024 — about 12% of all new cancer diagnoses that year — were attributable to infections that could potentially be prevented through treatment or vaccination.

Dr Gary Clifford, a scientist at IARC and the study's lead author, discussed the findings in an interview with France 24, highlighting the significant proportion of the global cancer burden that stems from preventable infectious causes.

Infections known to be linked to cancer risk include certain viruses and bacteria that can lead to cancers such as cervical, liver, and stomach cancer, among others, with vaccines and treatments available for several of the infections involved.

The findings underscore the potential for broader vaccination and infection-treatment programs, particularly in regions with higher rates of the relevant infections, to meaningfully reduce global cancer incidence over time.

The study did not, according to the available reporting, break down the 2.3 million cases by specific infection type or by region, though such details are typically included in the full IARC report.