A minority of patients requiring blood transfusions are increasingly requesting ‘unvaccinated’ blood in the United States, per a new report published in the journal Transfusion. Our studio guest today, genito-urinary consultant Vanessa Apea, explains how this can lead to potentially dangerous delays and higher risks.

Presenter Claudia Hammond speaks to Dr Angela Wu, from the Centre for Evidence-Based Medicine and Oxford Tobacco Addiction Group at the University of Oxford, about a new overview of the best available evidence worldwide for smoking cessation. The study, published in the journal Addiction, has found that nicotine‑containing e‑cigarettes appear to be more effective for stopping people smoking than other interventions.

We hear how metabolic liver disease could affect nearly 1.8 billion people by 2050, according to new research published in The Lancet Gastroenterology & Hepatology journal. The growing number of cases means that many people are at risk of developing serious complications, however, the study also found that although more people are developing the disease, the overall impact on health has remained stable due to advances in treatment and care.

We also hear from BBC World Service reporter Sen Nguyen in Vietnam as Hanoi plans to pilot a new low-emission zone from July to tackle air pollution. We hear what the proposed changes are and with the prevalence of diesel motorbikes in the city, how prepared are residents, workers and businesses for this change?

And Claudia and Vanessa discuss whether living with friends may quietly be altering your gut bacteria, following new research published in the journal Molecular Ecology.

Presenter: Claudia Hammond