Why fentanyl isn't so big in Australia? | Risks of under-vaccination | Breast cancer after an early scare | AI shaking up radiology

The addictive painkiller fentanyl has swept through the USA—but its effects haven't been as big in Australia. Why?

Vaccination against COVID-19 can save lives and reduce the risk of severe disease. Why are some people under vaccinated—and what's the risk for people not up to date with shots?

An early form of breast cancer—ductal carcinoma in situ (DCIS)—is often found by women themselves, not as part of screening programs.

The power and potential pitfalls of AI in medicine have been debated, but AI is already having an impact in radiology.