A Launceston General Hospital spokeswoman said its four patients suffering necrotizing fasciitis remained in a stable condition yesterday.

Director of Public Health Roscoe Taylor said the department was still waiting on data from the hospital before the investigation could start.

He said it was highly unlikely the cases were linked but it instead appeared to be a random event.

"Until we get individual records it's a bit hard to narrow down (the cause)," Dr Taylor said.

Necrotizing fasciitis is caused by a range of bacteria which enter the body through open wounds or small cuts, releasing toxins that rapidly kill flesh and muscle.

Dr Taylor said there was no need to panic as the disease was not transmissible between people.

He said the state saw a number of cases each year and had already counted 22 diagnoses in the last 12 months.

"In the last eight years, according to coding, the lowest was five and the highest was 28," he said.

Dr Taylor said people with diabetes, alcoholism, severe malnutrition, conditions that affect the vascular condition and injecting drug users were more at risk of contracting necrotizing fasciitis.

He encouraged people to refrain from smoking and maintain good physical activity and urged injecting drug users to use sterile equipment.