Nurse, the maggots
Maggots clean wounds 18 times faster than normal treatments, can conquer MRSA and would save the NHS millions. Peta Bee reports
It’s enough to make your skin crawl — yet flesh-eating maggots being applied to a festering wound that fails to heal could become a familiar sight in our hospitals. Last week Madeleine Moon, Labour MP for Bridgend, hailed maggots as an alternative to expensive antibiotic gels and lotions. She pointed out that maggots could speed recovery times, help to free hospital beds and fight MRSA. In a parliamentary motion backed by 35 MPs from all parties, she urged the Government to carry out clinical research into the widespread use of maggots.
Recent studies have indicated that maggot therapy can cut treatment duration from 89 days to just five, and slash the cost from £2,200 to £300 per patient.
Moon describes the grubs as “a highly cost-effective, highly efficient but forgotten and undervalued method of treatment”, and Caroline Flint, the Public Health Minister, says that using fly larvae (maggots) is “increasingly common” and “an illuminating idea”
In trials in Wales and Manchester, says Moon, patients not only recovered faster but noticed less smell and felt less pain from their rotting flesh when maggots were allowed to eat it. “Maggots are highly precise,” she says. “Unlike surgeons, they remove only the rotting tissue. Surgeons have to cut out healthy tissue to clear the wound, thereby creating a larger wound and more bleeding.”
Last year 30,000 NHS patients had maggots applied to their wounds. A study published in the Journal of Wound Care suggested that if larvae were used more widely the annual saving could be £162 million.
Maggot, or larval, therapy is not new. Civilisations worldwide, from Australian Aborigines to Burmese hill tribes and the Mayans, have used fly larvae to clean damaged wounds for centuries. During the First World War, Dr William Baer, of the Johns Hopkins School of Medicine in Baltimore, described finding two soldiers who had been wounded on the battlefield and left alone for days. When their clothes were removed, thousands of maggots were present in their wounds — yet beneath them the doctor was astonished to find clean, pink flesh. Baer renewed interest in maggots among the medical profession but it was short-lived; by the 1930s, with the arrival of antibiotics and modern surgical appproaches, they fell from favour.
But with the spread of resistance to antibiotics and the rise of “superbugs” such as MRSA, antibiotics are no longer considered the panacea they once were. Instead, the tiny grubs are squirming their way back into mainstream medicine. It is now known that enzymes produced when maggots eat rotting meat break down the dead tissue, which is sucked up and turned into new protein. Crucially, the enzymes stop working on contact with healthy or clean tissue, so when they are applied — either loosely beneath a bandage or inside a sealed bag — to a leg ulcer, for instance, they will consume only the rotting materials and leave the wound clean. Because they are regulated by the European Medicines Agency (EMEA), maggots used for medical purposes are considered pharmaceuticals and therefore had to undergo years of rigorous safety and efficacy tests before being approved for use on patients. Now, though, they are being introduced in hospitals from Belgium to Poland with reports of great success.
Of course, there is a glaring downside to maggot therapy, and one that may prove an impenetrable barrier to its mainstream use — namely the “yuck” factor. Yet researchers who have been investigating the medical benefits insist that, for the good of our health, we should disregard it.
Dr Stephen Britland, a reader in cell biology at the University of Bradford, says that much of the stigma attached to maggot therapy, although understandable, is entirely undeserved. “From a scientific point of view it is fascinating how maggots have evolved to get the nutrients they need to grow from a wound,” he says. “People think they are dirty, but maggots are very careful about what they do and carry out a very clean procedure.”
Among the pioneers of maggot treatment in the UK is ZooBiotic Ltd, one of the first profitable spin-off companies formed from an NHS trust — in this case the Bro Morgannwg Trust’s biosurgical research unit at the Princess of Wales Hospital, Bridgend. ZooBiotic farms maggots from the sterilised eggs of the common greenbottle, Lucila sericata. Its brand of sterile maggots, marketed as LarvE, was accepted for use by the NHS in 2004 and the company now supplies them to 3,800 hospitals in the UK.
“We keep the adult flies in 150 insect-rearing tanks, then collect their eggs and sterilise them,” says Dr Alan Morgan, the firm’s research director. “They are applied to a wound when they are tiny — smaller than a grain of rice — and can grow to more than a centimetre in length by the time they are removed.”
Morgan says that preliminary trials were conducted at the Princess of Wales Hospital on five patients with MRSA-infected wounds that were not responding to conventional antibiotic treatment. “In each case, treatment with maggots cleansed the wounds, eliminated the MRSA and allowed healing to commence in four days,” he says. A larger and more significant study at Manchester Royal Infirmary last year showed that maggot therapy reduced problems in 12 out of 13 cases of ulcers colonised by MRSA. “The maggots cleared the wounds of MRSA,” Morgan explains. “They don’t cure MRSA but they will reduce the chance of cross-infection and allow it to be treated effectively.”
What about those who really can’t bear the idea of maggots wriggling in their open wound? Dr Britland, who exudes enthusiasm about the grubs, says that an alternative means of gaining the benefits is on the horizon. Working with David Pritchard, a professor of parasite immunology at the University of Nottingham, he discovered that the fluid secreted by maggots to break down dead tissue so that it can be absorbed contains enzymes that have been shown to speed the healing process. In findings published last year in the journal Biotechnology Progress, they suggested that this juice works “by stimulating new cells to move to the wound site, where they can regenerate”.
Already, a prototype dressing in which the beneficial protease enzymes from cultured maggot juice are trapped in a gel-like substance and incorporated into bandages has been shown to work on layers of artificial skin. With funding from the Department of Trade and Industry, Dr Britland and Professor Pritchard now hope to show that it is effective on human beings. “Assuming that the initial stages of the study go well, we will be recruiting patients by the end of next year,” Dr Britland says. “When you get to the stage when maggots would normally be removed from a healing wound, you could keep the dressing on for longer, which would possibly stimulate the rebuilding of tissue and aid further recovery.”
Over the past decade, leeches and parasitic worms have also crawled back into favour as a treatment. Both have been used by doctors for centuries, and recent studies have shown that leeches are particularly effective in microsurgery that involves the reattachment of skin or body parts. It is thought that a natural anticoagulant secreted by the leeches fights blood clots and restores proper blood flow to inflamed body parts.
Another creepy-crawly gaining popularity among doctors is the parasitic helminth worm. These, unlike other parasitic worms, do not cause disease or invade other body parts. A 2004 study in the journal Gut found that patients with Crohn’s disease who swallowed a worm for a 24-week period showed significant improvement.
Meanwhile, at the University of York, the UK’s largest investigation into maggot therapy — involving 600 patients — is looking at precisely how effective it is in treating leg ulcers, which affect 1 per cent of the population and cost the NHS £600 million a year. In partnership with health trusts across the Midlands, in the North of England and in Northern Ireland, Dr Pauline Raynor and her colleagues in the department of health sciences will compare hydrogel, a commonly used caustic gel used for wound-cleaning, with sterile greenbottle larvae that are applied either loose (beneath a bandage) or in a gauze bag. “The bags are sometimes seen as an easier way to apply them,” Raynor says. “They are a bit more user-friendly.”
As leg ulcers are extremely painful, patients are often willing to try anything that might help to relieve their condition. “We sometimes have a job encouraging staff and nurses to use them — they are less willing than the patients,” she says.
Dr Iain Frame, research manager at Diabetes UK, is awaiting the York results with interest. He says that someone with diabetes has a 25 per cent chance of developing a foot ulcer at some time during their life — a statistic that makes diabetes the leading cause of nontraumatic lower limb amputation in the UK. People with the condition, who often suffer from nerve damage, may not notice an ulcer until it becomes infected, by which time it may be too late.
“In light of the increasing incidence of MRSA in our hospitals and resistance to antibiotics, maggot therapy could provide a viable alternative to treating wounds and diabetic foot ulcers,” Dr Frame says.
Maggots and their juices may even have medicinal uses beyond their flesh-eating, wound-healing ability. “We have isolated enzymes that can help with very different problems and we are preparing to study their effects,” says Dr Britland. “These are truly amazing creatures.”
Maggot therapy worked for me
Marlene Williams, 70, Bridgend, South Wales.
“Last June I had an accident in my kitchen when a hinge broke on a cupboard door and the door fell on to my shin like a guillotine. It left a gaping hole in my leg.
“I went to my local hospital, and they tried every conventional treatment on offer to get it to heal. District nurses were coming to my house all the time and used gels, honey, every kind of bandage imaginable, but even months later it wasn’t really getting better. “ When they suggested the maggots I thought they were joking. I’m not at all squeamish but I admit I cringed a bit when I saw them. I was in so much pain, though, and so fed up with my bad leg that anything was worth a try. The maggots were put in a sealed bag and attached to my leg so I couldn’t see them — but I definitely knew they were there. They seemed to become active at certain times of the day and I’d experience a tickling sensation, which I assume is when they were hungry and eating my skin. It’s strange to think that they were alive when they arrived and very much alive — and fatter — when they left. They grew 1cm during the time I had them on (about a week) but I am proof that they work.
“Within a couple of weeks my wound had healed. My friends now call me Marlene Maggot. I would recommend this treatment to anyone. I can’t believe the difference it has made.”
Saving money with maggots
ZooBiotic sells a pot of 300 maggots (enough to clean a typical ulcerated leg wound) for £55.
In a cost-effectiveness study conducted by ZooBiotic and published in the Journal of Wound Care, maggots were compared with hydrogel, the most commonly used conventional treatment for leg ulcers. On a patient-for-patient basis, the gel cost £2,200 per person and the maggots £300; annually, says Dr Alan Morgan of ZooBiotic, that equates to £184 million spent in treating wounds with conventional medication. With maggots the yearly cost would be £22 million — a saving of £162 million.
Dr Morgan says: “Between 80 and 90 per cent of the total cost of any therapy to treat wounds is not to do with raw materials, but with the cost of nursing time and care” — making maggots, with their shorter average healing time that they promote, considerably more economical.
I’d rather the surgeon’s knife
The value of maggots in removing irretrievably wound-damaged tissue — débridement — came into its own in the First World War. In trench warfare, wounded soldiers often had to lie out in no man’s land for hours, sometimes even a day or two, until they could be brought back by patrols after dark.
My father, who was a doctor for three years in the trenches, said that he always reassured the casualties whose wounds were playing host to maggots that, disgusting as they looked, they would hasten the healing of their wounds so that they would do better than comrades who had avoided the flies and maggots by being brought in earlier.
The cleaning of dead tissue and dirt from a wound to prevent infection is the essential first step for casualties in civilian life as well as those of wartime. Claims that maggots may have an antiseptic action that destroys bacteria are quite possibly true, but more important is that they remove the decaying tissue that makes a wonderful culture on which bacteria will flourish.
Bacteria, as they multiply, produce toxins that are carried round the body and cause the systemic ill-health that stems from infection.
Maggots may have been a useful aid at the time of Waterloo, on the Somme in 1916 or at Passchendaele in 1917 — but if hospitals were clean, I would opt for the speed of a competent surgeon’s cutting prowess with, if need be, the appropriate antibiotic if asepsis had failed to keep bacteria at bay.
Dr Thomas Stuttaford
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