A Taiwanese hospital's simple blood-and-stool test for a common stomach bug is winning global recognition and may spread to more countries, which is good news for cancer prevention.

• National Taiwan University Hospital spent two decades building a screening method that checks for both colon and stomach cancer risk at once.
• The bug it looks for, H. pylori, raises the risk of stomach cancer sixfold but can be treated with medication.
• Two of the world's biggest medical journals published the research and the related global guidelines, written with doctors from 20 countries.
• Bhutan already uses the method, eastern Europe may be next, and South American interest is stalled by political turmoil.
• Taiwan has screened 600,000 people so far, and about one in five tested positive.

Outlook: Countries with high infection rates — the US, Japan, South Korea and China — are the most likely next adopters, though rollout is slow.