← Listen againIn Conversation
Millions of cancer cases linked to infections, studies say October 2, 2026 · 4:46 · Health explained · With Maya and Grace
A new analysis estimates that infections were linked to 2.3 million new cancer cases worldwide in 2024. That was 12 percent of all cancer cases in that year, according to The BMJ.
Transcript Maya This is Slow English FM, with Health explained. Maya here. Grace covers health and medicine. Welcome, and thanks for listening. Maya A new analysis estimates that infections were linked to 2.3 million new cancer cases worldwide in 2024. That was 12 percent of all cancer cases in that year, according to The BMJ. Grace, what is the main public health message? Grace The analysis shows that infections are connected to a large number of cancer cases worldwide. It was conducted by the International Agency for Research on Cancer, known as IARC. The findings put infection prevention alongside other cancer prevention measures. Maya Which infections made the largest contributions in the analysis? Grace The BMJ reports that Helicobacter pylori was the leading infectious cause in the analysis. It was linked to about 760,000 cancer cases, mainly stomach cancer. Human papillomavirus, or HPV, was linked to about 750,000 cases, mainly cervical cancer. Hepatitis B virus was linked to about 360,000 cases, mainly liver cancer. Maya The word linked matters here. Does the analysis say that every person with one of these infections develops cancer? Grace No such conclusion is given in the supplied reports. The reports describe cases as attributable to infections. In this context, that means the analysis estimated how many cancer cases were connected to those infectious causes. It is a population estimate, not a statement that every infected person develops cancer. Maya How does the 2024 estimate compare with earlier global information? Grace The World Health Organization says that about 10 percent of cancers diagnosed worldwide in 2022 were linked to carcinogenic infections. The newer analysis gives an estimate of 12 percent for 2024. These figures come from different years and reports, so they provide context but do not by themselves explain the difference. Maya What does the World Health Organization say about prevention? Grace The World Health Organization says vaccination against HPV can reduce the risk of cervical cancer. It also says vaccination against hepatitis B can reduce the risk of liver cancer. Its cancer information identifies HPV as the main cause of cervical cancer. It also says that Helicobacter pylori is mainly linked to stomach cancer, while hepatitis B and hepatitis C can cause liver cancer. Maya So vaccination is important, but it is not the whole prevention picture. What else is identified in the sources? Grace The sources identify better water and sanitation, and stronger infection prevention and control, as important measures. IARC also says that infection-related cancers are decreasing in some places because of wider vaccination, better water and sanitation, and stronger infection prevention and control. The reported picture is therefore broader than vaccination alone. Maya Let us return to Helicobacter pylori. Why is it central to this analysis? Grace It was the largest infectious contributor reported by The BMJ. The study linked it to about 760,000 cancer cases, predominantly stomach cancer. About 410,000 of those cases occurred in East Asia. That figure shows that the global estimate includes different regional patterns. Maya What can listeners take from these findings without turning a global estimate into a personal diagnosis? Grace The analysis describes worldwide cancer patterns. Its public health message is that some cancer risks can be reduced through vaccination and other infection prevention measures. The World Health Organization specifically supports HPV and hepatitis B vaccination as ways to reduce the risk of certain cancers. Maya Grace, thank you for explaining the findings and their limits. This has been Health explained on Slow English FM. Thanks for listening.
