It is hard to diagnose because the infection can be mistaken as bruising, but the main difference is that the area is more painful that a bruise

Dr Liam McCaughey

Necrotizing fasciitis is caused by a bacterium called Group A streptoccocus (Strep A), which exists in the nose and throat or on the skin of many people without causing harm.

However, it can be lethal if it gets into an area such as the heart, lungs or muscles through broken skin or damaged tissue.

It then attacks the flesh, which dies causing the rest of the system to go into shock, leading to organ failure.

'Early diagnosis essential'

Dr McCaughey said that about eight cases a year were reported worldwide.

"This is an absolutely devastating disease. Up to 25% of those affected die," he said.

The dangers of necrotizing fasciitis were highlighted in the early 1990s when there were 17 cases in Gloucestershire.

If diagnosed in the time, the infection can be treated with antibiotics and surgery, sometimes including amputation.

Early symptoms include severe pain and swelling in the infected area, followed by the development of a purplish rash, accompanied by symptoms of nausea, diarrhoea, fever, confusion, dizziness and thirst.

In the advanced stages, the blood pressure of the victim drops sharply and they can suffer from toxic shock and unconsciousness.

Dr McCaughey said there was no way to guard against the disease, but that early diagnosis was essential.

"It is hard to diagnose because the infection can be mistaken as bruising, but the main difference is that the area is more painful that a bruise," he said.

"It can be very rapid once it establishes itself, often with a matter of between the infection and death."