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If you are reading this, it is likely that you have been asked to consider undergoing larval therapy as part of a course of wound treatment.
This page is intended to provide you with information on the technique and give answers to some of the questions you might have about the therapy.
Larval Therapy, also known as 'Maggot Therapy' or 'Biosurgery' involves the use of sterile larvae of the green bottle fly, which are introduced into a wound to remove unhealthy and infected tissue.
The technique, which has been used for centuries, has been reintroduced into modern medicine by doctors and wound care specialists who have found that larvae are able to cleanse wounds much more rapidly than conventional dressings.
Whilst larvae should not be regarded as a cure for all types of wounds, by removing dead tissue and any associated bacteria, in most instances they will improve the condition of a wound and allow the process of healing to begin.
The processes by which larvae clean wounds are very complex, but in simple terms they release special chemicals into the wound that breakdown dead tissue into a liquid form that the larvae can easily remove and digest.
During this process the actively feeding larvae also take up bacteria (germs), which are then destroyed within their gut.
This process is so effective that larvae can often convert an infected smelly wound into a clean healthy wound within a few days.
The larvae that will be applied to your wound are very small, only a few millimetres in length, smaller than a grain of rice. During the time that they are on the wound, however, they will increase in size as they eat away all the dead or infected tissue.
The fact that the larvae have increased in size when they are removed from the wound indicates that they are having the desired effect and that the treatment is working correctly.
Firstly, the larvae are enclosed within a BioFOAM dressing where they are contained inside a finely woven net. Small pieces of foam are also present to aid the growth of the larvae and help retain exudate. These 'dressings' come in varying sizes and are applied according to the nature and size of wound being treated. A simple absorbent pad, held in place with some surgical tape or bandage, completes the dressing.
The second method is where the larvae are applied directly onto the wound. This is commonly referred to as using 'free range' larvae. To ensure that the larvae are kept within the region of the wound, a special dressing system is applied, the exact nature of which is determined by the size and location of the area to be treated. In most instances, an adhesive dressing is used to form a border around the edge of the wound and protect the surrounding skin. The larvae are then placed in the wound and covered with a piece of finely woven mesh that is fixed firmly to the adhesive border. A simple absorbent pad, held in place with tape or a bandage, completes the dressing.
For more extensive wounds on the leg or foot, the larvae are applied directly to the wound and covered with a net boot or tube.
This can vary with each treatment of larvae and the method of application being used.
BioFOAM Dressings can generally be left in place for up to five days, although it is possible for the dressing to be removed on a daily basis to allow inspection of the wound site.
'Free Range' larvae are generally left in place for up to three days before being removed from the wound site. With both application methods however, it is impossible to predict how long a course of treatment will take. Sometimes a wound is completely cleansed by a single application of larvae but other wounds may require two or more treatments to achieve the desired effect.
During larvae therapy you may notice some changes in your wound:
The larvae used in wound management will not attack or burrow into healthy tissue, they only remove dead or unhealthy tissue.
It takes about 10-14 days for a newly hatched larva to complete its life cycle and turn into a fly. Larvae dressings are generally changed every 3-5 days so there is no chance that they will turn into flies during this time.
Only adult flies can lay eggs, so the larvae cannot reproduce or multiply within the wound.
Although it is possible to carry out most normal activities whilst undergoing larvae therapy, you should ideally not bathe or immerse your wound in water, particularly when 'free range' larvae are being applied. Although the larvae are unlikely to drown, excessive moisture may loosen the retaining dressing and allow them to escape.
It is also not a good idea to sit with the wound too close to a fire or other source of heat as the larvae may dry out.
Similarly, sitting or walking on a wound dressed with larvae should also be avoided as far as possible.
Clinical experience with larvae has shown that they can clean wounds in a fraction of the time taken by more conventional dressings, which could potentially speed up healing times. They are also useful in the management of infected wounds that contain bacteria that are difficult to kill with more conventional treatments.
Larvae have also been shown to be successful at eliminating MRSA from wounds.
Sterile larvae, under the brand name of LarvE, are produced in a special unit by highly trained staff at ZooBiotic Ltd, a company with many years experience in wound management.
