Fly maggots have been known for centuries to debride and heal wounds. Maggot debridement therapy (MDT) was first introduced in the USA in 1931 and was routinely used there until mid-1940's in over 300 hospitals. With the advent of antibiotics, maggot therapy became rare until the early 1990's, when it was re-introduced first in the USA. Today, MDT is used in over 30 countries worldwide. This method has been used in over 2,000 medical institutions and over 20,000 patients have been treated in the last 20 years. Lately, this treatment modality received the approval from the national health authorities of USA, G. Britain, Germany, Austria and Israel.
Sterile maggots of the green bottle fly, Lucilia sericata, are used for MDT. Up to 1,000 maggots are introduced in the wound and left for 1-3 days. Maggots are applied by using a cage-like dressing, where the maggots are concealed within a netting, which prevents the maggot from escaping but allows air to reach the maggots and facilitates the drainage of liquefied necrotic tissue through the top of the dressing. Recently, the Biobag method was introduced for MDT. Maggots are enclosed between two layers of polyvinylalcohol-hydro-sponge netting, which are glued together over a small cube of a spacer material. The maggots are thus able to feed through the dressing and their secretions reach the wound in order to control infection and stimulate healing. The advantages claimed for this method are: a) No need to a cage-like dressing; the bags are applied directly on the wound and kept on the spot with the help of gauze and bandages alone; b) Reduced pain as there is no mechanical irritation of the wound edges by growing maggots, and c) Maggots cannot escape from the Biobag, which is essential for hospital hygiene and patients acceptance of MDT.
MDT could be used for any kind of purulent, sloughy wound on the skin, independent of the underlying diseases or the location on the body for ambulatory as well as for hospitalized patients. MDT has been used successfully for abscesses, burns, cellulitis, gangrene, and ulcers due to arterial disease, venous stasis, lymphostasis, Burgerís disease, neuropathies, paraplegia, hemiplegia, osteomyelitis mastoiditis, thalassemia, polycythemia, dementia and basal cell carcinoma. This method has been recommended especially for patients with diabetic foot ulcers and pressure ulcers. One of the major advantages of MDT is that the maggots separate the necrotic tissue from the living tissue, making a surgical debridement easier. In 80-95% of the cases, a complete or significant debridement of the wound is achieved. As therapy progresses, new layers of healthy tissue are formed over the wounds. There is a significant decrease of the offensive odor emanating from the necrotic tissue and from intense pain accompanying the wound. In a significant number of patients, an immediate amputation can be prevented because of MDT. In other cases, a more proximal amputation could be avoided. It is also possible that in patients with deep wounds, where septicemia is a serious threat, this can be prevented because of MDT.
MDT proved to be an effective method in cleaning chronic wounds and initiating granulation. It is a simple, efficient, safe and cost-effective tool for the treatment of wounds and ulcers, which do not respond to conventional treatment and surgical intervention.
An International Biotherapy Society for the promotion of MDT was created in 1996 and since then six international conferences on biotherapy have been held.
Sterile maggots are being produced and marketed by private companies in the UK, Germany and USA, while sterile maggots are produced in over 15 laboratories worldwide.