A medical dressing that changes colour when it detects infection could cut the unnecessary use of antibiotics, say scientists at Bath University.

It works by releasing fluorescent dye from tiny capsules when toxins are given out by bacteria in a wound. This allows doctors to identify bacterial infections and treat them more quickly, particularly in children with burns.

Researchers said it could help to save lives. Infections can slow the healing of wounds, leading to longer stays in hospital and sometimes permanent scarring. In severe cases, infections can kill.

Doctors find it very difficult to diagnose infections quickly and easily without removing the dressing, which can be painful and create more scarring.

Because of this, antibiotics are often prescribed as a precaution before the infection is confirmed.

However, treatment with antibiotics when there is no infection can lead to bacteria becoming resistant to antibiotics - and antibiotic resistance is a major health concern.