England's chief medical officer is urging global leaders to tackle the growing threat of antibiotic resistance.

Medical experts say these drugs are being used too much, and that 25,000 people die across Europe each year because of drug-resistant infections.

Professor Dame Sally Davies says she is "really worried" that without effective antibiotics, common medical procedures such as caesarean sections and cancer treatments could become too risky.

She is attending a meeting in Berlin of health officials around the world, to discuss a "call to action" to tackle the problem.