Lethal 'flesh-eating' bug numbers on rise

Research from Otago University has found the numbers of people with a potentially lethal 'flesh eating' bug is on the rise. Photo / Thinkstock

A potentially lethal 'flesh-eating' bacterial infection is afflicting increasing numbers of New Zealanders, new research shows.

University of Otago researchers this morning released the a first ever nation-wide assessment of the incidence of necrotising fasciitis, or 'flesh-eating disease'.

It shows the disease has risen from fewer than 10 cases a year in 1990 to more than 70 cases a year in 2006.

The study identified 812 cases between 1990 and 2006, of whom 148 died - a 21 per cent fatality rate.

Necrotising fasciitis is a severe bacterial infection that causes rapid destruction of soft tissue.

Most severely affected people need extensive surgery and sometimes limb amputation.

Associate Professor Michael Baker said the rising incidence of the disease was a cause for concern.

It was in line with a wider worrying increase in serious infectious diseases across New Zealand, he said.

"Although this disease remains uncommon, it's feared because of its speed of onset, high fatality rate, and the severe tissue damage its causes."

A necrotising fasciitis infection can start with a minor skin injury or wound before progressing to severe local pain and a high fever, Dr Baker said.

"The pain is caused by a very rapid spread of the infection into deep soft tissue and is not always obvious from first inspection of the skin. Rapid treatment is absolutely vital to save lives."

The research found Maori and Pacific people, older people, and men are most vulnerable to necrotising fasciitis infection - though the reasons that are not clear.

Causes of rising infection rates may include greater virulence of the bacteria, decreased resistance because of other chronic illnesses, environmental factors such as a rise in household overcrowding, and decreased access to health services because of rising socio-economic inequality, Dr Baker said.

Science fiction writer Peter Watts blogged about his experiences after contracting necrotising fasciitis in his leg earlier this year.

King Herod the Great reportedly suffered necrotising fasciitis of the groin and genitalia at the time of his death.