Imagine a treatment for serious wounds that is almost guaranteed to heal quickly and completely (100% effective, according to a study released last week), that is low-cost and has no reported side effects, and that cannot be undermined by our growing intolerance of manufactured antibiotics. Imagine, too, that there are no ethical objections to its use, and that its efficacy has been proven not only by recent research but by centuries of documented medical usage. There could, surely, be no logical reason for its use to be restricted to those hospitals - and specifically a handful of consultants - who overlook the fact that this treatment does not appear on the list of approved medicines and is banned in GP surgeries.
The rare application of larval therapy on the wards, though, perhaps has less to do with logical reasons than it does with the rather squeamish responses - from patients and some of those in the medical profession - to a treatment which, on the face of it, could be a gift from the gods to the cash-strapped, time-pressed NHS. The fact is that the mere notion of introducing a gaggle of live maggots into an open wound is enough to have the fainthearted leaping from their sickbeds.
A paper released last week from specialists at West Cumberland hospital in Cumbria could make them think again. Twelve patients with serious, "sloughy" leg ulcers took part in the study; six of them were treated with conventional hydrogel therapy, six with larval therapy (a more reassuring term for maggots). After one application of maggots, left in the wound for three days, all six of these patients were left with clean wounds. Of the others, only two had clean wounds after a month of treatment, with the other four needing further medical attention.
"It was a small pilot study to prove that the maggots were a valid purchase," says Anne Walker, a leg ulcer specialist nurse at the hospital. "We needed evidence of cost-effectiveness, and there was no research on this. We knew how effective the treatment was - we've been using maggots since 1997 - but we were so amazed with this outcome that we decided we had to publish it."
The use of maggots in treating serious wounds is well documented, although one commonly held view is that the creatures were best left festering in the trenches. In fact, larval therapy did survive for a while after its successful use in the first world war and American civil war: it was widely used in the 1930s in America, and declined only with the arrival of antibiotics in the 1940s. So why is it back?
"It's gone full circle," says Dr Steve Thomas, director of the biosurgical research unit at the surgical materials testing laboratory (SMTL) in Bridgend, Glamorgan, which supplies sterile maggots to hospitals across the UK. "With the problems of modern antibiotics, there is a tendency to go back to nature." And maggots can achieve naturally what manufactured medicines are increasingly failing to do: wipe out the superbugs, such as methicillin-resistant Staphylococcus aureus (MRSA), which outsmart more conventional antibiotics.
"A wound can have sloughy or necrotic tissue fixed to it," says Walker. "Maggots excrete an enzyme which softens the dead tissue, and then they ingest all the slough and bacteria, without damaging the good tissue."
A dressing protects healthy skin from these enzymes and a sterile mesh rules out any risk of escape. And only rarely can a patient feel the creatures going about their business.
Despite the evidence of larval therapy's amazing efficiency, squeamishness still plays a part in hindering its widespread adoption. The reticence comes from an unexpected quarter, however. "We have used maggots in over a hundred cases," says Walker, "and not once have we had a patient decline the treatment. If you explain that they don't have to see it, and that they usually won't feel it, they're quite happy."
"Maggots aren't sexy, they're not high-technology, they're not expensive and they don't require expertise," says Thomas. "For some the problem is a physical loathing - it's as simple as that. And it's the medical profession which is the most squeamish."
It is perhaps understandable, though, that many in the profession are reluctant to make use of techniques that are associated with the more primitive eras of medicine. When a British woman travelled to America last February to have a hole drilled into her head in a desperate attempt to cure her depression, many doctors were horrified at the idea that the ancient technique of trepanning (once thought to release evil spirits from the brain) could still be in practice. However, the use of maggots and other creepy-crawlies - now known as biosurgery - has much stronger arguments in its favour.
Leeches were used for medicinal purposes as early as 200BC, but the practice of blood-letting, to cure everything from gout to headaches, lost its appeal in the 19th century. Now, patients who have lost an ear or a finger are likely to wake from surgery to find that their tissue is not the only thing that has been attached. Venous insufficiency, where poor circulation or blood clots threaten the reattached tissue, can be countered by the natural bloodsucking of the leech, which improves natural circulation by gorging itself on the patient's blood. Even after the creature has sated itself and fallen off, the patient will continue to bleed for an average of 10 hours, preventing clots and gangrene.
"The public likes the idea of using things that are natural," says Thomas, who believes that we will increasingly see the use of remedies such as honey, which competes with bacteria for moisture, thereby drying out and healing infected wounds.
The stumbling block will not be patient reticence or even staff repulsion - Walker says that most nurses are enthusiastic once they have been trained to apply the maggots properly - but rather more mundane problems: cost and bureaucracy.
"We have a trust that recognises that new treatments can be very cost-effective," says Walker. "Some trusts find the maggots too expensive, which means that it's not available to everybody." She points out that while the larval therapy can initially be more expensive to purchase, the speed with which the maggots clean up wounds make them highly economical. In the West Cumberland study, the average cost per patient for larval therapy was £78.64. The cost for those on conventional therapy was £136.23 - and two-thirds of those patients required yet more treatment.
Discussions with the drug tariff authorities are under way to try to secure prescription status for larval therapy. Only 20% of wound dressings are carried out in hospitals and fans of the maggot believe that it could be hugely beneficial for community nursing and in doctors' surgeries.
Ironically, the SMTL larvae were last November granted Millennium Product status (they don't appear in the Millennium Dome as they have a tendency to turn into flies). Archaic it may be, but maggot therapy is officially a 21st century treatment. Its only problem now is that it has come up against that age-old complaint: red tape.
