The squiggly creatures, being bred in labs here, not only are helping doctors save lives and limbs worldwide, they're drawing attention to a region quietly developing into one of Britain's leading biotechnology centres.

Once doctors and their patients overcome the squeamishness of using fly larvae and bloodsucking worms to treat serious wounds, they find maggots and leeches contribute to cleaning and healing better than anything produced by man, distributors say. ``More and more people are coming around,'' says Dr Stephen Thomas, a wound-therapy expert who heads the maggot-producing biosurgical research unit at the Princess of Wales hospital in Bridgend.

South Wales is home to what are billed as the only commercial producers and exporters of maggots and leeches in the world. Inside Dr Thomas' unit,workers are hunched over petri dishes, separating fly eggs to be individually sterilised. Sterilisation is the hard part and the process is a closely guarded secret.Our maggots are cleaner than the patient,'' Thomas boasts.

The sterile, two-mm maggots that hatch offspring of a common coppery green housefly known as the green bottle are herded into glass beakers labeled with the larvae brand name, and shipped around the world.

Price: 53 pounds for 80 to 100 hungry, squirming maggots.

Since the unit opened three years ago, about 4,000 doses have gone out, primarily to Britain and the rest of Europe.

The larvae are applied to open wounds that have been stubborn to heal, usually when all other treatments have failed. Covered with a thin net bandage to keep them inside, the maggots eat dead, decaying skin and make way for new tissue to grow. They get into places antibiotics can't reach, don't attack living tissue and, in about three days are clamoring to get out.

David Powell, a 36-year-old musician fromPorthcaul, Wales, is sold. Stubborn ulcers on both of his heels got so bad over the years that doctors were talking amputation. Desperate, Powell agreed on maggots. In three weeks, he says, they had cleaned the wound quite dramatically and will probably end up saving his feet.

The leeches bred and exported by Swansea-based Biopharm Ltd probably are a rung or two above maggots on the respect scale, having gotten lots of publicity in the past decade for their unique role in restoring blood circulation to grafted tissue and surgically reattached digits, limbs and even ears.

The use of leeches is at least as old as medical literature, with the first references appearing as early as 130 BC. At various times, they were used to treat complaints ranging from epilepsy and obesity to hemorrhoids. Leeches are back in vogue because researchers have been unable to match the potency and effectiveness of their natural anti-coagulants, Gower says.

``There's really nothing new in science and medicine,'' Dr Upton says inthe New York medical journal MD. "The resourceful physician looks to nature for solutions.''