A carnivorous pack of bacteria has struck terror in parts of the US and Europe. Known as group A streptococcus, the bacteria, say researchers, can cause a fatal drop in blood pressure, toxic shock and organ failure. In their most macabre form, they eat away human flesh.

Over the past 6 months, the microbe has claimed a dozen lives in the UK. Scientists are concerned because the symptoms are often ignored in the early stages of the disease, when it can be treated.