“Can I buy a bottle of maggots?”
This was a question I fielded from a Vancouver area clinician who had a serious problem. She had a patient who had travelled 200 kilometers to have her diabetic foot ulcer treated with larvae as an outpatient in Vancouver. A bottle of sterile blowfly larvae from a medical maggot production facility in California was held up at the border and had passed its best-before date. The patient’s wounds were getting worse. Could we produce maggots at UBC to help treat people with this problem?
The use of sterile medical maggots of the green blow fly, Phaenicia serciata, to remove dead tissue from wounds (maggot debridement therapy, or MDT), was well-established in the early 20th century. Since the time of the Napoleonic wars, physicians were purposely introducing fly larvae into infected wounds to clear dead tissue. Many U.S. and Canadian hospitals maintained insect-rearing facilities, while the pharmaceutical company Laederle provided pre-packaged dressings containing maggots.
With the advent of sulfonamides and other antibiotics, this practice declined after World War II. It was only brought back in the 1970s because it is more effective for certain types of complicated severe open wounds, such as the foot ulcers diabetics suffer. Large-scale studies have demonstrated that patients benefit from faster healing and lower treatment costs, and in some cases MDT allows the saving of digits and limbs that would otherwise require amputation.
In the U.S., MDT is licensed by the Food and Drug Administration as a medical device. In the U.K. a government sponsored laboratory produces MDT for the treatment of 30,000 patients per year.
If you total the spinal cord, diabetic and leg ulcer patients in Canada, an estimated 235,000 people suffer from chronic, non-healing wounds per year. The average cost of treatment over three months – a typical scenario with this kind of wound – can be as high as $27,000. But more importantly, there are very human costs and consequences of chronic open, infected skin lesions: the wounds are very painful, malodorous and require constant intensive management. The morbidity and negative outcomes of chronic skin wounds in immune compromised, diabetic and bedridden patients has led wound care practitioners, currently mostly nurse clinicians, to seek alternative therapies such as MDT.
But why hasn’t MDT caught on in Canada? There are lots of reasons, including poor awareness, limited availability of larvae, lack of regulatory approval, no incentives for pharmaceutical companies, lack of buy-in by traditionally trained surgeons… And, perhaps, the yuck factor.
In a modern health care system that is looking for more effective treatments at a lower cost, it may be time to get past our squeamishness and embrace maggot therapy.